[object Object]

Applications running in Node.js will generally experience the following categories of errors:

  • Standard JavaScript errors such as <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/EvalError" class="type"><EvalError></a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/SyntaxError" class="type"><SyntaxError></a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RangeError" class="type"><RangeError></a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ReferenceError" class="type"><ReferenceError></a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypeError" class="type"><TypeError></a>, and <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/URIError" class="type"><URIError></a>.
  • Standard DOMExceptions.
  • System errors triggered by underlying operating system constraints such as attempting to open a file that does not exist or attempting to send data over a closed socket.
  • AssertionErrors are a special class of error that can be triggered when Node.js detects an exceptional logic violation that should never occur. These are raised typically by the node:assert module.
  • User-specified errors triggered by application code.

All JavaScript and system errors raised by Node.js inherit from, or are instances of, the standard JavaScript <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a> class and are guaranteed to provide at least the properties available on that class.

The error.message property of errors raised by Node.js may be changed in any versions. Use error.code to identify an error instead. For a DOMException, use domException.name to identify its type.

[object Object]

Node.js supports several mechanisms for propagating and handling errors that occur while an application is running. How these errors are reported and handled depends entirely on the type of Error and the style of the API that is called.

All JavaScript errors are handled as exceptions that immediately generate and throw an error using the standard JavaScript throw mechanism. These are handled using the try…catch construct provided by the JavaScript language.

// Throws with a ReferenceError because z is not defined.
try {
  const m = 1;
  const n = m + z;
} catch (err) {
  // Handle the error here.
}

Any use of the JavaScript throw mechanism will raise an exception that must be handled or the Node.js process will exit immediately.

With few exceptions, Synchronous APIs (any blocking method that does not return a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a> nor accept a callback function, such as fs.readFileSync), will use throw to report errors.

Errors that occur within Asynchronous APIs may be reported in multiple ways:

  • Some asynchronous methods returns a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise" class="type"><Promise></a>, you should always take into account that it might be rejected. See --unhandled-rejections flag for how the process will react to an unhandled promise rejection.

    const fs = require('node:fs/promises');
    
    (async () => {
      let data;
      try {
        data = await fs.readFile('a file that does not exist');
      } catch (err) {
        console.error('There was an error reading the file!', err);
        return;
      }
      // Otherwise handle the data
    })();
    
  • Most asynchronous methods that accept a callback function will accept an Error object passed as the first argument to that function. If that first argument is not null and is an instance of Error, then an error occurred that should be handled.

    const fs = require('node:fs');
    fs.readFile('a file that does not exist', (err, data) => {
      if (err) {
        console.error('There was an error reading the file!', err);
        return;
      }
      // Otherwise handle the data
    });
    
  • When an asynchronous method is called on an object that is an EventEmitter, errors can be routed to that object's 'error' event.

    const net = require('node:net');
    const connection = net.connect('localhost');
    
    // Adding an 'error' event handler to a stream:
    connection.on('error', (err) => {
      // If the connection is reset by the server, or if it can't
      // connect at all, or on any sort of error encountered by
      // the connection, the error will be sent here.
      console.error(err);
    });
    
    connection.pipe(process.stdout);
    
  • A handful of typically asynchronous methods in the Node.js API may still use the throw mechanism to raise exceptions that must be handled using try…catch. There is no comprehensive list of such methods; please refer to the documentation of each method to determine the appropriate error handling mechanism required.

The use of the 'error' event mechanism is most common for stream-based and event emitter-based APIs, which themselves represent a series of asynchronous operations over time (as opposed to a single operation that may pass or fail).

For all EventEmitter objects, if an 'error' event handler is not provided, the error will be thrown, causing the Node.js process to report an uncaught exception and crash unless either: a handler has been registered for the 'uncaughtException' event, or the deprecated node:domain module is used.

const EventEmitter = require('node:events');
const ee = new EventEmitter();

setImmediate(() => {
  // This will crash the process because no 'error' event
  // handler has been added.
  ee.emit('error', new Error('This will crash'));
});

Errors generated in this way cannot be intercepted using try…catch as they are thrown after the calling code has already exited.

Developers must refer to the documentation for each method to determine exactly how errors raised by those methods are propagated.

[object Object]

A generic JavaScript <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a> object that does not denote any specific circumstance of why the error occurred. Error objects capture a "stack trace" detailing the point in the code at which the Error was instantiated, and may provide a text description of the error.

All errors generated by Node.js, including all system and JavaScript errors, will either be instances of, or inherit from, the Error class.

[object Object]
  • message <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>
  • options <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a>
    • cause <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> The error that caused the newly created error.

Creates a new Error object and sets the error.message property to the provided text message. If an object is passed as message, the text message is generated by calling String(message). If the cause option is provided, it is assigned to the error.cause property. The error.stack property will represent the point in the code at which new Error() was called. Stack traces are dependent on V8's stack trace API. Stack traces extend only to either (a) the beginning of synchronous code execution, or (b) the number of frames given by the property Error.stackTraceLimit, whichever is smaller.

[object Object]
  • targetObject <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a>
  • constructorOpt <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a>

Creates a .stack property on targetObject, which when accessed returns a string representing the location in the code at which Error.captureStackTrace() was called.

const myObject = {};
Error.captureStackTrace(myObject);
myObject.stack;  // Similar to `new Error().stack`

The first line of the trace will be prefixed with ${myObject.name}: ${myObject.message}.

The optional constructorOpt argument accepts a function. If given, all frames above constructorOpt, including constructorOpt, will be omitted from the generated stack trace.

The constructorOpt argument is useful for hiding implementation details of error generation from the user. For instance:

function a() {
  b();
}

function b() {
  c();
}

function c() {
  // Create an error without stack trace to avoid calculating the stack trace twice.
  const { stackTraceLimit } = Error;
  Error.stackTraceLimit = 0;
  const error = new Error();
  Error.stackTraceLimit = stackTraceLimit;

  // Capture the stack trace above function b
  Error.captureStackTrace(error, b); // Neither function c, nor b is included in the stack trace
  throw error;
}

a();
[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#number_type" class="type"><number></a>

The Error.stackTraceLimit property specifies the number of stack frames collected by a stack trace (whether generated by new Error().stack or Error.captureStackTrace(obj)).

The default value is 10 but may be set to any valid JavaScript number. Changes will affect any stack trace captured after the value has been changed.

If set to a non-number value, or set to a negative number, stack traces will not capture any frames.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a>

If present, the error.cause property is the underlying cause of the Error. It is used when catching an error and throwing a new one with a different message or code in order to still have access to the original error.

The error.cause property is typically set by calling new Error(message, { cause }). It is not set by the constructor if the cause option is not provided.

This property allows errors to be chained. When serializing Error objects, util.inspect() recursively serializes error.cause if it is set.

const cause = new Error('The remote HTTP server responded with a 500 status');
const symptom = new Error('The message failed to send', { cause });

console.log(symptom);
// Prints:
//   Error: The message failed to send
//       at REPL2:1:17
//       at Script.runInThisContext (node:vm:130:12)
//       ... 7 lines matching cause stack trace ...
//       at [_line] [as _line] (node:internal/readline/interface:886:18) {
//     [cause]: Error: The remote HTTP server responded with a 500 status
//         at REPL1:1:15
//         at Script.runInThisContext (node:vm:130:12)
//         at REPLServer.defaultEval (node:repl:574:29)
//         at bound (node:domain:426:15)
//         at REPLServer.runBound [as eval] (node:domain:437:12)
//         at REPLServer.onLine (node:repl:902:10)
//         at REPLServer.emit (node:events:549:35)
//         at REPLServer.emit (node:domain:482:12)
//         at [_onLine] [as _onLine] (node:internal/readline/interface:425:12)
//         at [_line] [as _line] (node:internal/readline/interface:886:18)
[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

The error.code property is a string label that identifies the kind of error. error.code is the most stable way to identify an error. It will only change between major versions of Node.js. In contrast, error.message strings may change between any versions of Node.js. See Node.js error codes for details about specific codes.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

The error.message property is the string description of the error as set by calling new Error(message). The message passed to the constructor will also appear in the first line of the stack trace of the Error, however changing this property after the Error object is created may not change the first line of the stack trace (for example, when error.stack is read before this property is changed).

const err = new Error('The message');
console.error(err.message);
// Prints: The message
[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

The error.stack property is a string describing the point in the code at which the Error was instantiated.

Error: Things keep happening!
   at /home/gbusey/file.js:525:2
   at Frobnicator.refrobulate (/home/gbusey/business-logic.js:424:21)
   at Actor.<anonymous> (/home/gbusey/actors.js:400:8)
   at increaseSynergy (/home/gbusey/actors.js:701:6)

The first line is formatted as <error class name>: <error message>, and is followed by a series of stack frames (each line beginning with "at "). Each frame describes a call site within the code that lead to the error being generated. V8 attempts to display a name for each function (by variable name, function name, or object method name), but occasionally it will not be able to find a suitable name. If V8 cannot determine a name for the function, only location information will be displayed for that frame. Otherwise, the determined function name will be displayed with location information appended in parentheses.

Frames are only generated for JavaScript functions. If, for example, execution synchronously passes through a C++ addon function called cheetahify which itself calls a JavaScript function, the frame representing the cheetahify call will not be present in the stack traces:

const cheetahify = require('./native-binding.node');

function makeFaster() {
  // `cheetahify()` *synchronously* calls speedy.
  cheetahify(function speedy() {
    throw new Error('oh no!');
  });
}

makeFaster();
// will throw:
//   /home/gbusey/file.js:6
//       throw new Error('oh no!');
//           ^
//   Error: oh no!
//       at speedy (/home/gbusey/file.js:6:11)
//       at makeFaster (/home/gbusey/file.js:5:3)
//       at Object.<anonymous> (/home/gbusey/file.js:10:1)
//       at Module._compile (module.js:456:26)
//       at Object.Module._extensions..js (module.js:474:10)
//       at Module.load (module.js:356:32)
//       at Function.Module._load (module.js:312:12)
//       at Function.Module.runMain (module.js:497:10)
//       at startup (node.js:119:16)
//       at node.js:906:3

The location information will be one of:

  • native, if the frame represents a call internal to V8 (as in [].forEach).
  • plain-filename.js:line:column, if the frame represents a call internal to Node.js.
  • /absolute/path/to/file.js:line:column, if the frame represents a call in a user program (using CommonJS module system), or its dependencies.
  • <transport-protocol>:///url/to/module/file.mjs:line:column, if the frame represents a call in a user program (using ES module system), or its dependencies.

The number of frames captured by the stack trace is bounded by the smaller of Error.stackTraceLimit or the number of available frames on the current event loop tick.

error.stack is a getter/setter for a hidden internal property which is only present on builtin Error objects (those for which Error.isError returns true). If error is not a builtin error object, then the error.stack getter will always return undefined, and the setter will do nothing. This can occur if the accessor is manually invoked with a this value that is not a builtin error object, such as a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy" class="type"><Proxy></a>.

[object Object]
  • Extends: <a href="errors.html#class-error" class="type"><errors.Error></a>

Indicates the failure of an assertion. For details, see Class: assert.AssertionError.

[object Object]
  • Extends: <a href="errors.html#class-error" class="type"><errors.Error></a>

Indicates that a provided argument was not within the set or range of acceptable values for a function; whether that is a numeric range, or outside the set of options for a given function parameter.

require('node:net').connect(-1);
// Throws "RangeError: "port" option should be >= 0 and < 65536: -1"

Node.js will generate and throw RangeError instances immediately as a form of argument validation.

[object Object]
  • Extends: <a href="errors.html#class-error" class="type"><errors.Error></a>

Indicates that an attempt is being made to access a variable that is not defined. Such errors commonly indicate typos in code, or an otherwise broken program.

While client code may generate and propagate these errors, in practice, only V8 will do so.

doesNotExist;
// Throws ReferenceError, doesNotExist is not a variable in this program.

Unless an application is dynamically generating and running code, ReferenceError instances indicate a bug in the code or its dependencies.

[object Object]
  • Extends: <a href="errors.html#class-error" class="type"><errors.Error></a>

Indicates that a program is not valid JavaScript. These errors may only be generated and propagated as a result of code evaluation. Code evaluation may happen as a result of eval, Function, require, or vm. These errors are almost always indicative of a broken program.

try {
  require('node:vm').runInThisContext('binary ! isNotOk');
} catch (err) {
  // 'err' will be a SyntaxError.
}

SyntaxError instances are unrecoverable in the context that created them – they may only be caught by other contexts.

[object Object]
  • Extends: <a href="errors.html#class-error" class="type"><errors.Error></a>

Node.js generates system errors when exceptions occur within its runtime environment. These usually occur when an application violates an operating system constraint. For example, a system error will occur if an application attempts to read a file that does not exist.

  • address <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a> If present, the address to which a network connection failed
  • code <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a> The string error code
  • dest <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a> If present, the file path destination when reporting a file system error
  • errno <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#number_type" class="type"><number></a> The system-provided error number
  • info <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> If present, extra details about the error condition
  • message <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a> A system-provided human-readable description of the error
  • path <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a> If present, the file path when reporting a file system error
  • port <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#number_type" class="type"><number></a> If present, the network connection port that is not available
  • syscall <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a> The name of the system call that triggered the error
[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

If present, error.address is a string describing the address to which a network connection failed.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

The error.code property is a string representing the error code.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

If present, error.dest is the file path destination when reporting a file system error.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#number_type" class="type"><number></a>

The error.errno property is a negative number which corresponds to the error code defined in libuv Error handling.

On Windows the error number provided by the system will be normalized by libuv.

To get the string representation of the error code, use util.getSystemErrorName(error.errno).

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a>

If present, error.info is an object with details about the error condition.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

error.message is a system-provided human-readable description of the error.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

If present, error.path is a string containing a relevant invalid pathname.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#number_type" class="type"><number></a>

If present, error.port is the network connection port that is not available.

[object Object]
  • Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>

The error.syscall property is a string describing the syscall that failed.

[object Object]

This is a list of system errors commonly-encountered when writing a Node.js program. For a comprehensive list, see the errno(3) man page.

  • EACCES (Permission denied): An attempt was made to access a file in a way forbidden by its file access permissions.

  • EADDRINUSE (Address already in use): An attempt to bind a server (net, http, or https) to a local address failed due to another server on the local system already occupying that address.

  • ECONNREFUSED (Connection refused): No connection could be made because the target machine actively refused it. This usually results from trying to connect to a service that is inactive on the foreign host.

  • ECONNRESET (Connection reset by peer): A connection was forcibly closed by a peer. This normally results from a loss of the connection on the remote socket due to a timeout or reboot. Commonly encountered via the http and net modules.

  • EEXIST (File exists): An existing file was the target of an operation that required that the target not exist.

  • EISDIR (Is a directory): An operation expected a file, but the given pathname was a directory.

  • EMFILE (Too many open files in system): Maximum number of file descriptors allowable on the system has been reached, and requests for another descriptor cannot be fulfilled until at least one has been closed. This is encountered when opening many files at once in parallel, especially on systems (in particular, macOS) where there is a low file descriptor limit for processes. To remedy a low limit, run ulimit -n 2048 in the same shell that will run the Node.js process.

  • ENOENT (No such file or directory): Commonly raised by fs operations to indicate that a component of the specified pathname does not exist. No entity (file or directory) could be found by the given path.

  • ENOTDIR (Not a directory): A component of the given pathname existed, but was not a directory as expected. Commonly raised by fs.readdir.

  • ENOTEMPTY (Directory not empty): A directory with entries was the target of an operation that requires an empty directory, usually fs.unlink.

  • ENOTFOUND (DNS lookup failed): Indicates a DNS failure of either EAI_NODATA or EAI_NONAME. This is not a standard POSIX error.

  • EPERM (Operation not permitted): An attempt was made to perform an operation that requires elevated privileges.

  • EPIPE (Broken pipe): A write on a pipe, socket, or FIFO for which there is no process to read the data. Commonly encountered at the net and http layers, indicative that the remote side of the stream being written to has been closed.

  • ETIMEDOUT (Operation timed out): A connect or send request failed because the connected party did not properly respond after a period of time. Usually encountered by http or net. Often a sign that a socket.end() was not properly called.

[object Object]
  • Extends <a href="errors.html#class-error" class="type"><errors.Error></a>

Indicates that a provided argument is not an allowable type. For example, passing a function to a parameter which expects a string would be a TypeError.

require('node:url').parse(() => { });
// Throws TypeError, since it expected a string.

Node.js will generate and throw TypeError instances immediately as a form of argument validation.

[object Object]

A JavaScript exception is a value that is thrown as a result of an invalid operation or as the target of a throw statement. While it is not required that these values are instances of Error or classes which inherit from Error, all exceptions thrown by Node.js or the JavaScript runtime will be instances of Error.

Some exceptions are unrecoverable at the JavaScript layer. Such exceptions will always cause the Node.js process to crash. Examples include assert() checks or abort() calls in the C++ layer.

[object Object]

Errors originating in crypto or tls are of class Error, and in addition to the standard .code and .message properties, may have some additional OpenSSL-specific properties.

[object Object]

An array of errors that can give context to where in the OpenSSL library an error originates from.

[object Object]

The OpenSSL function the error originates in.

[object Object]

The OpenSSL library the error originates in.

[object Object]

A human-readable string describing the reason for the error.

[object Object]

[object Object]

Used when an operation has been aborted (typically using an AbortController).

APIs not using AbortSignals typically do not raise an error with this code.

This code does not use the regular ERR_* convention Node.js errors use in order to be compatible with the web platform's AbortError.

[object Object]

A special type of error that is triggered whenever Node.js tries to get access to a resource restricted by the Permission Model.

[object Object]

A function argument is being used in a way that suggests that the function signature may be misunderstood. This is thrown by the node:assert module when the message parameter in assert.throws(block, message) matches the error message thrown by block because that usage suggests that the user believes message is the expected message rather than the message the AssertionError will display if block does not throw.

[object Object]

An iterable argument (i.e. a value that works with for...of loops) was required, but not provided to a Node.js API.

[object Object]

A special type of error that can be triggered whenever Node.js detects an exceptional logic violation that should never occur. These are raised typically by the node:assert module.

[object Object]

An attempt was made to register something that is not a function as an AsyncHooks callback.

[object Object]

An operation related to module loading is customized by an asynchronous loader hook that never settled the promise before the loader thread exits.

[object Object]

The type of an asynchronous resource was invalid. Users are also able to define their own types if using the public embedder API.

[object Object]

Data passed to a Brotli stream was not successfully compressed.

[object Object]

An invalid parameter key was passed during construction of a Brotli stream.

[object Object]

An attempt was made to create a Node.js Buffer instance from addon or embedder code, while in a JS engine Context that is not associated with a Node.js instance. The data passed to the Buffer method will have been released by the time the method returns.

When encountering this error, a possible alternative to creating a Buffer instance is to create a normal Uint8Array, which only differs in the prototype of the resulting object. Uint8Arrays are generally accepted in all Node.js core APIs where Buffers are; they are available in all Contexts.

[object Object]

An operation outside the bounds of a Buffer was attempted.

[object Object]

An attempt has been made to create a Buffer larger than the maximum allowed size.

[object Object]

Node.js was unable to watch for the SIGINT signal.

[object Object]

A child process was closed before the parent received a reply.

[object Object]

Used when a child process is being forked without specifying an IPC channel.

[object Object]

Used when the main process is trying to read data from the child process's STDERR/STDOUT, and the data's length is longer than the maxBuffer option.

[object Object]

There was an attempt to use a MessagePort instance in a closed state, usually after .close() has been called.

[object Object]

Console was instantiated without stdout stream, or Console has a non-writable stdout or stderr stream.

[object Object]

A class constructor was called that is not callable.

[object Object]

A constructor for a class was called without new.

[object Object]

The vm context passed into the API is not yet initialized. This could happen when an error occurs (and is caught) during the creation of the context, for example, when the allocation fails or the maximum call stack size is reached when the context is created.

[object Object]

The CPU profile with the given name is already started.

[object Object]

The CPU profile with the given name is not started.

[object Object]

There are too many CPU profiles being collected.

[object Object]

Argon2 is not supported by the current version of OpenSSL being used.

[object Object]

An OpenSSL engine was requested (for example, through the clientCertEngine or privateKeyEngine TLS options) that is not supported by the version of OpenSSL being used, likely due to the compile-time flag OPENSSL_NO_ENGINE.

[object Object]

An invalid value for the format argument was passed to the crypto.ECDH() class getPublicKey() method.

[object Object]

An invalid value for the key argument has been passed to the crypto.ECDH() class computeSecret() method. It means that the public key lies outside of the elliptic curve.

[object Object]

An invalid crypto engine identifier was passed to require('node:crypto').setEngine().

[object Object]

The --force-fips command-line argument was used but there was an attempt to enable or disable FIPS mode in the node:crypto module.

[object Object]

An attempt was made to enable or disable FIPS mode, but FIPS mode was not available.

[object Object]

hash.digest() was called multiple times. The hash.digest() method must be called no more than one time per instance of a Hash object.

[object Object]

hash.update() failed for any reason. This should rarely, if ever, happen.

[object Object]

The given crypto keys are incompatible with the attempted operation.

[object Object]

The selected public or private key encoding is incompatible with other options.

[object Object]

Initialization of the crypto subsystem failed.

[object Object]

An invalid authentication tag was provided.

[object Object]

An invalid counter was provided for a counter-mode cipher.

[object Object]

An invalid elliptic-curve was provided.

[object Object]

An invalid crypto digest algorithm was specified.

[object Object]

An invalid initialization vector was provided.

[object Object]

An invalid JSON Web Key was provided.

[object Object]

An invalid key length was provided.

[object Object]

An invalid key pair was provided.

[object Object]

An invalid key type was provided.

[object Object]

The given crypto key object's type is invalid for the attempted operation.

[object Object]

An invalid message length was provided.

[object Object]

One or more crypto.scrypt() or crypto.scryptSync() parameters are outside their legal range.

[object Object]

A crypto method was used on an object that was in an invalid state. For instance, calling cipher.getAuthTag() before calling cipher.final().

[object Object]

An invalid authentication tag length was provided.

[object Object]

Initialization of an asynchronous crypto operation failed.

[object Object]

Key's Elliptic Curve is not registered for use in the JSON Web Key Elliptic Curve Registry.

[object Object]

Key's Asymmetric Key Type is not registered for use in the JSON Web Key Types Registry.

[object Object]

Attempted to use KEM operations while Node.js was not compiled with OpenSSL with KEM support.

[object Object]

A crypto operation failed for an otherwise unspecified reason.

[object Object]

The PBKDF2 algorithm failed for unspecified reasons. OpenSSL does not provide more details and therefore neither does Node.js.

[object Object]

Node.js was compiled without scrypt support. Not possible with the official release binaries but can happen with custom builds, including distro builds.

[object Object]

A signing key was not provided to the sign.sign() method.

[object Object]

crypto.timingSafeEqual() was called with Buffer, TypedArray, or DataView arguments of different lengths.

[object Object]

An unknown cipher was specified.

[object Object]

An unknown Diffie-Hellman group name was given. See crypto.getDiffieHellman() for a list of valid group names.

[object Object]

An attempt to invoke an unsupported crypto operation was made.

[object Object]

An error occurred with the debugger.

[object Object]

The debugger timed out waiting for the required host/port to be free.

[object Object]

The fs.Dir was previously closed.

[object Object]

A synchronous read or close call was attempted on an fs.Dir which has ongoing asynchronous operations.

[object Object]

Loading native addons has been disabled using --no-addons.

[object Object]

A call to process.dlopen() failed.

[object Object]

c-ares failed to set the DNS server.

[object Object]

The node:domain module was not usable since it could not establish the required error handling hooks, because process.setUncaughtExceptionCaptureCallback() had been called at an earlier point in time.

[object Object]

process.setUncaughtExceptionCaptureCallback() could not be called because the node:domain module has been loaded at an earlier point in time.

The stack trace is extended to include the point in time at which the node:domain module had been loaded.

[object Object]

v8.startupSnapshot.setDeserializeMainFunction() could not be called because it had already been called before.

[object Object]

Data provided to TextDecoder() API was invalid according to the encoding provided.

[object Object]

Encoding provided to TextDecoder() API was not one of the WHATWG Supported Encodings.

[object Object]

--print cannot be used with ESM input.

[object Object]

Thrown when an attempt is made to recursively dispatch an event on EventTarget.

[object Object]

The JS execution context is not associated with a Node.js environment. This may occur when Node.js is used as an embedded library and some hooks for the JS engine are not set up properly.

[object Object]

A Promise that was callbackified via util.callbackify() was rejected with a falsy value.

[object Object]

Used when a feature that is not available to the current platform which is running Node.js is used.

[object Object]

An attempt was made to copy a directory to a non-directory (file, symlink, etc.) using fs.cp().

[object Object]

An attempt was made to copy over a file that already existed with fs.cp(), with the force and errorOnExist set to true.

[object Object]

When using fs.cp(), src or dest pointed to an invalid path.

[object Object]

An attempt was made to copy a named pipe with fs.cp().

[object Object]

An attempt was made to copy a non-directory (file, symlink, etc.) to a directory using fs.cp().

[object Object]

An attempt was made to copy to a socket with fs.cp().

[object Object]

When using fs.cp(), a symlink in dest pointed to a subdirectory of src.

[object Object]

An attempt was made to copy to an unknown file type with fs.cp().

[object Object]

Path is a directory.

[object Object]

An attempt was made to read a file larger than the supported 2 GiB limit for fs.readFile(). This is not a limitation of Buffer, but an internal I/O constraint. For handling larger files, consider using fs.createReadStream() to read the file in chunks.

[object Object]

The number of file system events queued without being handled exceeded the size specified in maxQueue in fs.watch().

[object Object]

HTTP/2 ALTSVC frames require a valid origin.

[object Object]

HTTP/2 ALTSVC frames are limited to a maximum of 16,382 payload bytes.

[object Object]

For HTTP/2 requests using the CONNECT method, the :authority pseudo-header is required.

[object Object]

For HTTP/2 requests using the CONNECT method, the :path pseudo-header is forbidden.

[object Object]

For HTTP/2 requests using the CONNECT method, the :scheme pseudo-header is forbidden.

[object Object]

A non-specific HTTP/2 error has occurred.

[object Object]

New HTTP/2 Streams may not be opened after the Http2Session has received a GOAWAY frame from the connected peer.

[object Object]

An additional headers was specified after an HTTP/2 response was initiated.

[object Object]

An attempt was made to send multiple response headers.

[object Object]

Multiple values were provided for an HTTP/2 header field that was required to have only a single value.

[object Object]

Informational HTTP status codes (1xx) may not be set as the response status code on HTTP/2 responses.

[object Object]

HTTP/1 connection specific headers are forbidden to be used in HTTP/2 requests and responses.

[object Object]

An invalid HTTP/2 header value was specified.

[object Object]

An invalid HTTP informational status code has been specified. Informational status codes must be an integer between 100 and 199 (inclusive).

[object Object]

HTTP/2 ORIGIN frames require a valid origin.

[object Object]

Input Buffer and Uint8Array instances passed to the http2.getUnpackedSettings() API must have a length that is a multiple of six.

[object Object]

Only valid HTTP/2 pseudoheaders (:status, :path, :authority, :scheme, and :method) may be used.

[object Object]

An action was performed on an Http2Session object that had already been destroyed.

[object Object]

An invalid value has been specified for an HTTP/2 setting.

[object Object]

An operation was performed on a stream that had already been destroyed.

[object Object]

Whenever an HTTP/2 SETTINGS frame is sent to a connected peer, the peer is required to send an acknowledgment that it has received and applied the new SETTINGS. By default, a maximum number of unacknowledged SETTINGS frames may be sent at any given time. This error code is used when that limit has been reached.

[object Object]

An attempt was made to initiate a new push stream from within a push stream. Nested push streams are not permitted.

[object Object]

Out of memory when using the http2session.setLocalWindowSize(windowSize) API.

[object Object]

An attempt was made to directly manipulate (read, write, pause, resume, etc.) a socket attached to an Http2Session.

[object Object]

HTTP/2 ORIGIN frames are limited to a length of 16382 bytes.

[object Object]

The number of streams created on a single HTTP/2 session reached the maximum limit.

[object Object]

A message payload was specified for an HTTP response code for which a payload is forbidden.

[object Object]

An HTTP/2 ping was canceled.

[object Object]

HTTP/2 ping payloads must be exactly 8 bytes in length.

[object Object]

An HTTP/2 pseudo-header has been used inappropriately. Pseudo-headers are header key names that begin with the : prefix.

[object Object]

An attempt was made to create a push stream, which had been disabled by the client.

[object Object]

An attempt was made to use the Http2Stream.prototype.responseWithFile() API to send a directory.

[object Object]

An attempt was made to use the Http2Stream.prototype.responseWithFile() API to send something other than a regular file, but offset or length options were provided.

[object Object]

The Http2Session closed with a non-zero error code.

[object Object]

The Http2Session settings canceled.

[object Object]

An attempt was made to connect a Http2Session object to a net.Socket or tls.TLSSocket that had already been bound to another Http2Session object.

[object Object]

An attempt was made to use the socket property of an Http2Session that has already been closed.

[object Object]

Use of the 101 Informational status code is forbidden in HTTP/2.

[object Object]

An invalid HTTP status code has been specified. Status codes must be an integer between 100 and 599 (inclusive).

[object Object]

An Http2Stream was destroyed before any data was transmitted to the connected peer.

[object Object]

A non-zero error code was been specified in an RST_STREAM frame.

[object Object]

When setting the priority for an HTTP/2 stream, the stream may be marked as a dependency for a parent stream. This error code is used when an attempt is made to mark a stream and dependent of itself.

[object Object]

The number of supported custom settings (10) has been exceeded.

[object Object]

The limit of acceptable invalid HTTP/2 protocol frames sent by the peer, as specified through the maxSessionInvalidFrames option, has been exceeded.

[object Object]

The number of uniq origin sent by the server has exceeded the value defined in options.maxOriginSetSize.

[object Object]

Trailing headers have already been sent on the Http2Stream.

[object Object]

The http2stream.sendTrailers() method cannot be called until after the 'wantTrailers' event is emitted on an Http2Stream object. The 'wantTrailers' event will only be emitted if the waitForTrailers option is set for the Http2Stream.

[object Object]

http2.connect() was passed a URL that uses any protocol other than http: or https:.

[object Object]

An error is thrown when writing to an HTTP response which does not allow contents.

[object Object]

Response body size doesn't match with the specified content-length header value.

[object Object]

An attempt was made to add more headers after the headers had already been sent.

[object Object]

An invalid HTTP header value was specified.

[object Object]

Status code was outside the regular status code range (100-999).

[object Object]

The client has not sent the entire request within the allowed time.

[object Object]

The given ServerResponse was already assigned a socket.

[object Object]

Changing the socket encoding is not allowed per RFC 7230 Section 3.

[object Object]

The Trailer header was set even though the transfer encoding does not support that.

[object Object]

An attempt was made to construct an object using a non-public constructor.

[object Object]

An import attribute is missing, preventing the specified module to be imported.

[object Object]

An import type attribute was provided, but the specified module is of a different type.

[object Object]

An import attribute is not supported by this version of Node.js.

[object Object]

An option pair is incompatible with each other and cannot be used at the same time.

[object Object]

The --input-type flag was used to attempt to execute a file. This flag can only be used with input via --eval, --print, or STDIN.

[object Object]

While using the node:inspector module, an attempt was made to activate the inspector when it already started to listen on a port. Use inspector.close() before activating it on a different address.

[object Object]

While using the node:inspector module, an attempt was made to connect when the inspector was already connected.

[object Object]

While using the node:inspector module, an attempt was made to use the inspector after the session had already closed.

[object Object]

An error occurred while issuing a command via the node:inspector module.

[object Object]

The inspector is not active when inspector.waitForDebugger() is called.

[object Object]

The node:inspector module is not available for use.

[object Object]

While using the node:inspector module, an attempt was made to use the inspector before it was connected.

[object Object]

An API was called on the main thread that can only be used from the worker thread.

[object Object]

There was a bug in Node.js or incorrect usage of Node.js internals. To fix the error, open an issue at https://github.com/nodejs/node/issues.

[object Object]

The provided address is not understood by the Node.js API.

[object Object]

The provided address family is not understood by the Node.js API.

[object Object]

An argument of the wrong type was passed to a Node.js API.

[object Object]

An invalid or unsupported value was passed for a given argument.

[object Object]

An invalid asyncId or triggerAsyncId was passed using AsyncHooks. An id less than -1 should never happen.

[object Object]

A swap was performed on a Buffer but its size was not compatible with the operation.

[object Object]

Invalid characters were detected in headers.

[object Object]

A cursor on a given stream cannot be moved to a specified row without a specified column.

[object Object]

A file descriptor ('fd') was not valid (e.g. it was a negative value).

[object Object]

A file descriptor ('fd') type was not valid.

[object Object]

A Node.js API that consumes file: URLs (such as certain functions in the fs module) encountered a file URL with an incompatible host. This situation can only occur on Unix-like systems where only localhost or an empty host is supported.

[object Object]

A Node.js API that consumes file: URLs (such as certain functions in the fs module) encountered a file URL with an incompatible path. The exact semantics for determining whether a path can be used is platform-dependent.

The thrown error object includes an input property that contains the URL object of the invalid file: URL.

[object Object]

An attempt was made to send an unsupported "handle" over an IPC communication channel to a child process. See subprocess.send() and process.send() for more information.

[object Object]

An invalid HTTP token was supplied.

[object Object]

An IP address is not valid.

[object Object]

The syntax of a MIME is not valid.

[object Object]

An attempt was made to load a module that does not exist or was otherwise not valid.

[object Object]

The imported module string is an invalid URL, package name, or package subpath specifier.

[object Object]

An error occurred while setting an invalid attribute on the property of an object.

[object Object]

An invalid package.json file failed parsing.

[object Object]

The package.json "exports" field contains an invalid target mapping value for the attempted module resolution.

[object Object]

An invalid options.protocol was passed to http.request().

[object Object]

Both breakEvalOnSigint and eval options were set in the REPL config, which is not supported.

[object Object]

The input may not be used in the REPL. The conditions under which this error is used are described in the REPL documentation.

[object Object]

Thrown in case a function option does not provide a valid value for one of its returned object properties on execution.

[object Object]

Thrown in case a function option does not provide an expected value type for one of its returned object properties on execution.

[object Object]

Thrown in case a function option does not return an expected value type on execution, such as when a function is expected to return a promise.

[object Object]

Indicates that an operation cannot be completed due to an invalid state. For instance, an object may have already been destroyed, or may be performing another operation.

[object Object]

A Buffer, TypedArray, DataView, or string was provided as stdio input to an asynchronous fork. See the documentation for the child_process module for more information.

[object Object]

A Node.js API function was called with an incompatible this value.

const urlSearchParams = new URLSearchParams('foo=bar&baz=new');

const buf = Buffer.alloc(1);
urlSearchParams.has.call(buf, 'foo');
// Throws a TypeError with code 'ERR_INVALID_THIS'

[object Object]

An element in the iterable provided to the WHATWG URLSearchParams constructor did not represent a [name, value] tuple – that is, if an element is not iterable, or does not consist of exactly two elements.

[object Object]

The provided TypeScript syntax is not valid.

[object Object]

An invalid URI was passed.

[object Object]

An invalid URL was passed to the WHATWG URL constructor or the legacy url.parse() to be parsed. The thrown error object typically has an additional property 'input' that contains the URL that failed to parse.

[object Object]

An invalid URLPattern was passed to the WHATWG URLPattern constructor to be parsed.

[object Object]

An attempt was made to use a URL of an incompatible scheme (protocol) for a specific purpose. It is only used in the WHATWG URL API support in the fs module (which only accepts URLs with 'file' scheme), but may be used in other Node.js APIs as well in the future.

[object Object]

An attempt was made to use an IPC communication channel that was already closed.

[object Object]

An attempt was made to disconnect an IPC communication channel that was already disconnected. See the documentation for the child_process module for more information.

[object Object]

An attempt was made to create a child Node.js process using more than one IPC communication channel. See the documentation for the child_process module for more information.

[object Object]

An attempt was made to open an IPC communication channel with a synchronously forked Node.js process. See the documentation for the child_process module for more information.

[object Object]

IP is blocked by net.BlockList.

[object Object]

An ESM loader hook returned without calling next() and without explicitly signaling a short circuit.

[object Object]

An error occurred while loading a SQLite extension.

[object Object]

An attempt was made to allocate memory (usually in the C++ layer) but it failed.

[object Object]

A message posted to a MessagePort could not be deserialized in the target vm Context. Not all Node.js objects can be successfully instantiated in any context at this time, and attempting to transfer them using postMessage() can fail on the receiving side in that case.

[object Object]

A method is required but not implemented.

[object Object]

A required argument of a Node.js API was not passed. This is only used for strict compliance with the API specification (which in some cases may accept func(undefined) but not func()). In most native Node.js APIs, func(undefined) and func() are treated identically, and the ERR_INVALID_ARG_TYPE error code may be used instead.

[object Object]

For APIs that accept options objects, some options might be mandatory. This code is thrown if a required option is missing.

[object Object]

An attempt was made to read an encrypted key without specifying a passphrase.

[object Object]

The V8 platform used by this instance of Node.js does not support creating Workers. This is caused by lack of embedder support for Workers. In particular, this error will not occur with standard builds of Node.js.

[object Object]

A module can not be linked because the same module requests in it are not resolved to the same module.

[object Object]

A module file could not be resolved by the ECMAScript modules loader while attempting an import operation or when loading the program entry point.

[object Object]

A callback was called more than once.

A callback is almost always meant to only be called once as the query can either be fulfilled or rejected but not both at the same time. The latter would be possible by calling a callback more than once.

[object Object]

While using Node-API, a constructor passed was not a function.

[object Object]

While calling napi_create_dataview(), a given offset was outside the bounds of the dataview or offset + length was larger than a length of given buffer.

[object Object]

While calling napi_create_typedarray(), the provided offset was not a multiple of the element size.

[object Object]

While calling napi_create_typedarray(), (length * size_of_element) + byte_offset was larger than the length of given buffer.

[object Object]

An error occurred while invoking the JavaScript portion of the thread-safe function.

[object Object]

An error occurred while attempting to retrieve the JavaScript undefined value.

[object Object]

A non-context-aware native addon was loaded in a process that disallows them.

[object Object]

An attempt was made to use operations that can only be used when building V8 startup snapshot even though Node.js isn't building one.

[object Object]

The operation cannot be performed when it's not in a single-executable application.

[object Object]

An attempt was made to perform operations that are not supported when building a startup snapshot.

[object Object]

An attempt was made to use crypto features while Node.js was not compiled with OpenSSL crypto support.

[object Object]

An attempt was made to use features that require ICU, but Node.js was not compiled with ICU support.

[object Object]

An attempt was made to use features that require Native TypeScript support, but Node.js was not compiled with TypeScript support.

[object Object]

An operation failed. This is typically used to signal the general failure of an asynchronous operation.

[object Object]

An attempt was made to get options before the bootstrapping was completed.

[object Object]

A given value is out of the accepted range.

[object Object]

The package.json "imports" field does not define the given internal package specifier mapping.

[object Object]

The package.json "exports" field does not export the requested subpath. Because exports are encapsulated, private internal modules that are not exported cannot be imported through the package resolution, unless using an absolute URL.

[object Object]

When strict set to true, thrown by util.parseArgs() if a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#boolean_type" class="type"><boolean></a> value is provided for an option of type <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a>, or if a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#string_type" class="type"><string></a> value is provided for an option of type <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#boolean_type" class="type"><boolean></a>.

[object Object]

Thrown by util.parseArgs(), when a positional argument is provided and allowPositionals is set to false.

[object Object]

When strict set to true, thrown by util.parseArgs() if an argument is not configured in options.

[object Object]

An invalid timestamp value was provided for a performance mark or measure.

[object Object]

Invalid options were provided for a performance measure.

[object Object]

Accessing Object.prototype.__proto__ has been forbidden using --disable-proto=throw. Object.getPrototypeOf and Object.setPrototypeOf should be used to get and set the prototype of an object.

[object Object]

Failed to proxy a request because the proxy configuration is invalid.

[object Object]

Failed to establish proxy tunnel when NODE_USE_ENV_PROXY or --use-env-proxy is enabled.

[object Object]

Stability: 1 - Experimental

A QUIC application error occurred.

[object Object]

Stability: 1 - Experimental

Establishing a QUIC connection failed.

[object Object]

Stability: 1 - Experimental

A QUIC Endpoint closed with an error.

[object Object]

Stability: 1 - Experimental

Opening a QUIC stream failed.

[object Object]

Stability: 1 - Experimental

A QUIC transport error occurred.

[object Object]

Stability: 1 - Experimental

A QUIC session failed because version negotiation is required.

[object Object]

When trying to require() a ES Module, the module turns out to be asynchronous. That is, it contains top-level await.

To see where the top-level await is, use --experimental-print-required-tla (this would execute the modules before looking for the top-level awaits).

[object Object]

When trying to require() a ES Module, a CommonJS to ESM or ESM to CommonJS edge participates in an immediate cycle. This is not allowed because ES Modules cannot be evaluated while they are already being evaluated.

To avoid the cycle, the require() call involved in a cycle should not happen at the top-level of either an ES Module (via createRequire()) or a CommonJS module, and should be done lazily in an inner function.

[object Object]

Stability: 0 - Deprecated

An attempt was made to require() an ES Module.

This error has been deprecated since require() now supports loading synchronous ES modules. When require() encounters an ES module that contains top-level await, it will throw ERR_REQUIRE_ASYNC_MODULE instead.

[object Object]

Stability: 1 - Experimental.

An attempt was made to require() an ES Module while another import() call was already in progress to load it asynchronously.

[object Object]

Script execution was interrupted by SIGINT (For example, Ctrl+C was pressed.)

[object Object]

Script execution timed out, possibly due to bugs in the script being executed.

[object Object]

The server.listen() method was called while a net.Server was already listening. This applies to all instances of net.Server, including HTTP, HTTPS, and HTTP/2 Server instances.

[object Object]

The server.close() method was called when a net.Server was not running. This applies to all instances of net.Server, including HTTP, HTTPS, and HTTP/2 Server instances.

[object Object]

A key was passed to single executable application APIs to identify an asset, but no match could be found.

[object Object]

An attempt was made to bind a socket that has already been bound.

[object Object]

An invalid (negative) size was passed for either the recvBufferSize or sendBufferSize options in dgram.createSocket().

[object Object]

An API function expecting a port >= 0 and < 65536 received an invalid value.

[object Object]

An API function expecting a socket type (udp4 or udp6) received an invalid value.

[object Object]

While using dgram.createSocket(), the size of the receive or send Buffer could not be determined.

[object Object]

An attempt was made to operate on an already closed socket.

[object Object]

When calling net.Socket.write() on a connecting socket and the socket was closed before the connection was established.

[object Object]

The socket was unable to connect to any address returned by the DNS within the allowed timeout when using the family autoselection algorithm.

[object Object]

A dgram.connect() call was made on an already connected socket.

[object Object]

A dgram.disconnect() or dgram.remoteAddress() call was made on a disconnected socket.

[object Object]

A call was made and the UDP subsystem was not running.

[object Object]

The source map could not be parsed because it does not exist, or is corrupt.

[object Object]

A file imported from a source map was not found.

[object Object]

The provided module import does not provide a source phase imports representation for source phase import syntax import source x from 'x' or import.source(x).

[object Object]

An error was returned from SQLite.

[object Object]

A string was provided for a Subresource Integrity check, but was unable to be parsed. Check the format of integrity attributes by looking at the Subresource Integrity specification.

[object Object]

A stream method was called that cannot complete because the stream was finished.

[object Object]

An attempt was made to call stream.pipe() on a Writable stream.

[object Object]

A stream method was called that cannot complete because the stream was destroyed using stream.destroy().

[object Object]

An attempt was made to call stream.write() with a null chunk.

[object Object]

An error returned by stream.finished() and stream.pipeline(), when a stream or a pipeline ends non gracefully with no explicit error.

[object Object]

An attempt was made to call stream.push() after a null(EOF) had been pushed to the stream.

[object Object]

An attempt was made to pipe to a closed or destroyed stream in a pipeline.

[object Object]

An attempt was made to call stream.unshift() after the 'end' event was emitted.

[object Object]

Prevents an abort if a string decoder was set on the Socket or if the decoder is in objectMode.

const Socket = require('node:net').Socket;
const instance = new Socket();

instance.setEncoding('utf8');

[object Object]

An attempt was made to call stream.write() after stream.end() has been called.

[object Object]

An attempt has been made to create a string longer than the maximum allowed length.

[object Object]

An artificial error object used to capture the call stack for diagnostic reports.

[object Object]

An unspecified or non-specific system error has occurred within the Node.js process. The error object will have an err.info object property with additional details.

[object Object]

This error represents a failed test. Additional information about the failure is available via the cause property. The failureType property specifies what the test was doing when the failure occurred.

[object Object]

This error is thrown when an ALPNCallback returns a value that is not in the list of ALPN protocols offered by the client.

[object Object]

This error is thrown when creating a TLSServer if the TLS options include both ALPNProtocols and ALPNCallback. These options are mutually exclusive.

[object Object]

This error is thrown by checkServerIdentity if a user-supplied subjectaltname property violates encoding rules. Certificate objects produced by Node.js itself always comply with encoding rules and will never cause this error.

[object Object]

While using TLS, the host name/IP of the peer did not match any of the subjectAltNames in its certificate.

[object Object]

While using TLS, the parameter offered for the Diffie-Hellman (DH) key-agreement protocol is too small. By default, the key length must be greater than or equal to 1024 bits to avoid vulnerabilities, even though it is strongly recommended to use 2048 bits or larger for stronger security.

[object Object]

A TLS/SSL handshake timed out. In this case, the server must also abort the connection.

[object Object]

The context must be a SecureContext.

[object Object]

The specified secureProtocol method is invalid. It is either unknown, or disabled because it is insecure.

[object Object]

Valid TLS protocol versions are 'TLSv1', 'TLSv1.1', or 'TLSv1.2'.

[object Object]

The TLS socket must be connected and securely established. Ensure the 'secure' event is emitted before continuing.

[object Object]

Attempting to set a TLS protocol minVersion or maxVersion conflicts with an attempt to set the secureProtocol explicitly. Use one mechanism or the other.

[object Object]

Failed to set PSK identity hint. Hint may be too long.

[object Object]

An attempt was made to renegotiate TLS on a socket instance with renegotiation disabled.

[object Object]

While using TLS, the server.addContext() method was called without providing a host name in the first parameter.

[object Object]

An excessive amount of TLS renegotiations is detected, which is a potential vector for denial-of-service attacks.

[object Object]

An attempt was made to issue Server Name Indication from a TLS server-side socket, which is only valid from a client.

[object Object]

The trace_events.createTracing() method requires at least one trace event category.

[object Object]

The node:trace_events module could not be loaded because Node.js was compiled with the --without-v8-platform flag.

[object Object]

Trailing junk found after the end of the compressed stream. This error is thrown when extra, unexpected data is detected after the end of a compressed stream (for example, in zlib or gzip decompression).

[object Object]

A Transform stream finished while it was still transforming.

[object Object]

A Transform stream finished with data still in the write buffer.

[object Object]

The initialization of a TTY failed due to a system error.

[object Object]

Function was called within a process.on('exit') handler that shouldn't be called within process.on('exit') handler.

[object Object]

process.setUncaughtExceptionCaptureCallback() was called twice, without first resetting the callback to null.

This error is designed to prevent accidentally overwriting a callback registered from another module.

[object Object]

A string that contained unescaped characters was received.

[object Object]

An unhandled error occurred (for instance, when an 'error' event is emitted by an EventEmitter but an 'error' handler is not registered).

[object Object]

Used to identify a specific kind of internal Node.js error that should not typically be triggered by user code. Instances of this error point to an internal bug within the Node.js binary itself.

[object Object]

A Unix group or user identifier that does not exist was passed.

[object Object]

An invalid or unknown encoding option was passed to an API.

[object Object]

An attempt was made to load a module with an unknown or unsupported file extension.

[object Object]

An attempt was made to load a module with an unknown or unsupported format.

[object Object]

An invalid or unknown process signal was passed to an API expecting a valid signal (such as subprocess.kill()).

[object Object]

import a directory URL is unsupported. Instead, self-reference a package using its name and define a custom subpath in the "exports" field of the package.json file.

import './'; // unsupported
import './index.js'; // supported
import 'package-name'; // supported

[object Object]

import with URL schemes other than file and data is unsupported.

[object Object]

Type stripping is not supported for files descendent of a node_modules directory.

[object Object]

An attempt was made to resolve an invalid module referrer. This can happen when importing or calling import.meta.resolve() with either:

  • a bare specifier that is not a builtin module from a module whose URL scheme is not file.
  • a relative URL from a module whose URL scheme is not a special scheme.
try {
  // Trying to import the package 'bare-specifier' from a `data:` URL module:
  await import('data:text/javascript,import "bare-specifier"');
} catch (e) {
  console.log(e.code); // ERR_UNSUPPORTED_RESOLVE_REQUEST
}

[object Object]

The provided TypeScript syntax is unsupported. This could happen when using TypeScript syntax that requires transformation with type-stripping.

[object Object]

An attempt was made to use something that was already closed.

[object Object]

While using the Performance Timing API (perf_hooks), no valid performance entry types are found.

[object Object]

A dynamic import callback was not specified.

[object Object]

A dynamic import callback was invoked without --experimental-vm-modules.

[object Object]

The module attempted to be linked is not eligible for linking, because of one of the following reasons:

  • It has already been linked (linkingStatus is 'linked')
  • It is being linked (linkingStatus is 'linking')
  • Linking has failed for this module (linkingStatus is 'errored')

[object Object]

The cachedData option passed to a module constructor is invalid.

[object Object]

Cached data cannot be created for modules which have already been evaluated.

[object Object]

The module being returned from the linker function is from a different context than the parent module. Linked modules must share the same context.

[object Object]

The module was unable to be linked due to a failure.

[object Object]

The fulfilled value of a linking promise is not a vm.Module object.

[object Object]

The current module's status does not allow for this operation. The specific meaning of the error depends on the specific function.

[object Object]

The WASI instance has already started.

[object Object]

The WASI instance has not been started.

[object Object]

A feature requiring WebAssembly was used, but WebAssembly is not supported or has been disabled in the current environment (for example, when running with --jitless).

[object Object]

The Response that has been passed to WebAssembly.compileStreaming or to WebAssembly.instantiateStreaming is not a valid WebAssembly response.

[object Object]

The Worker initialization failed.

[object Object]

The execArgv option passed to the Worker constructor contains invalid flags.

[object Object]

Stability: 1.1 - Active development

The destination thread threw an error while processing a message sent via postMessageToThread().

[object Object]

Stability: 1.1 - Active development

The thread requested in postMessageToThread() is invalid or has no workerMessage listener.

[object Object]

Stability: 1.1 - Active development

The thread id requested in postMessageToThread() is the current thread id.

[object Object]

Stability: 1.1 - Active development

Sending a message via postMessageToThread() timed out.

[object Object]

An operation failed because the Worker instance is not currently running.

[object Object]

The Worker instance terminated because it reached its memory limit.

[object Object]

The path for the main script of a worker is neither an absolute path nor a relative path starting with ./ or ../.

[object Object]

All attempts at serializing an uncaught exception from a worker thread failed.

[object Object]

The requested functionality is not supported in worker threads.

[object Object]

Creation of a zlib object failed due to incorrect configuration.

[object Object]

An invalid parameter key was passed during construction of a Zstd stream.

[object Object]

Too much data was received for a chunk extensions. In order to protect against malicious or malconfigured clients, if more than 16 KiB of data is received then an Error with this code will be emitted.

[object Object]

Too much HTTP header data was received. In order to protect against malicious or malconfigured clients, if more than maxHeaderSize of HTTP header data is received then HTTP parsing will abort without a request or response object being created, and an Error with this code will be emitted.

[object Object]

Server is sending both a Content-Length header and Transfer-Encoding: chunked.

Transfer-Encoding: chunked allows the server to maintain an HTTP persistent connection for dynamically generated content. In this case, the Content-Length HTTP header cannot be used.

Use Content-Length or Transfer-Encoding: chunked.

[object Object]

A module file could not be resolved by the CommonJS modules loader while attempting a require() operation or when loading the program entry point.

[object Object]

Stability: 0 - Deprecated. These error codes are either inconsistent, or have been removed.

[object Object]

The value passed to postMessage() contained an object that is not supported for transferring.

[object Object]

The native call from process.cpuUsage could not be processed.

[object Object]

The UTF-16 encoding was used with hash.digest(). While the hash.digest() method does allow an encoding argument to be passed in, causing the method to return a string rather than a Buffer, the UTF-16 encoding (e.g. ucs or utf16le) is not supported.

[object Object]

An incompatible combination of options was passed to crypto.scrypt() or crypto.scryptSync(). New versions of Node.js use the error code ERR_INCOMPATIBLE_OPTION_PAIR instead, which is consistent with other APIs.

[object Object]

An invalid symlink type was passed to the fs.symlink() or fs.symlinkSync() methods.

[object Object]

Used when a failure occurs sending an individual frame on the HTTP/2 session.

[object Object]

Used when an HTTP/2 Headers Object is expected.

[object Object]

Used when a required header is missing in an HTTP/2 message.

[object Object]

HTTP/2 informational headers must only be sent prior to calling the Http2Stream.prototype.respond() method.

[object Object]

Used when an action has been performed on an HTTP/2 Stream that has already been closed.

[object Object]

Used when an invalid character is found in an HTTP response status message (reason phrase).

[object Object]

An import assertion has failed, preventing the specified module to be imported.

[object Object]

An import assertion is missing, preventing the specified module to be imported.

[object Object]

An import attribute is not supported by this version of Node.js.

[object Object]

A given index was out of the accepted range (e.g. negative offsets).

[object Object]

An invalid or unexpected value was passed in an options object.

[object Object]

An invalid or unknown file encoding was passed.

[object Object]

While using the Performance Timing API (perf_hooks), a performance mark is invalid.

[object Object]

An invalid transfer object was passed to postMessage().

[object Object]

An attempt was made to load a resource, but the resource did not match the integrity defined by the policy manifest. See the documentation for policy manifests for more information.

[object Object]

An attempt was made to load a resource, but the resource was not listed as a dependency from the location that attempted to load it. See the documentation for policy manifests for more information.

[object Object]

An attempt was made to load a policy manifest, but the manifest had multiple entries for a resource which did not match each other. Update the manifest entries to match in order to resolve this error. See the documentation for policy manifests for more information.

[object Object]

A policy manifest resource had an invalid value for one of its fields. Update the manifest entry to match in order to resolve this error. See the documentation for policy manifests for more information.

[object Object]

A policy manifest resource had an invalid value for one of its dependency mappings. Update the manifest entry to match to resolve this error. See the documentation for policy manifests for more information.

[object Object]

An attempt was made to load a policy manifest, but the manifest was unable to be parsed. See the documentation for policy manifests for more information.

[object Object]

An attempt was made to read from a policy manifest, but the manifest initialization has not yet taken place. This is likely a bug in Node.js.

[object Object]

A policy manifest was loaded, but had an unknown value for its "onerror" behavior. See the documentation for policy manifests for more information.

[object Object]

This error code was replaced by ERR_MISSING_TRANSFERABLE_IN_TRANSFER_LIST in Node.js 15.0.0, because it is no longer accurate as other types of transferable objects also exist now.

[object Object]

An object that needs to be explicitly listed in the transferList argument is in the object passed to a postMessage() call, but is not provided in the transferList for that call. Usually, this is a MessagePort.

In Node.js versions prior to v15.0.0, the error code being used here was ERR_MISSING_MESSAGE_PORT_IN_TRANSFER_LIST. However, the set of transferable object types has been expanded to cover more types than MessagePort.

[object Object]

Used by the Node-API when Constructor.prototype is not an object.

[object Object]

On the main thread, values are removed from the queue associated with the thread-safe function in an idle loop. This error indicates that an error has occurred when attempting to start the loop.

[object Object]

Once no more items are left in the queue, the idle loop must be suspended. This error indicates that the idle loop has failed to stop.

[object Object]

A Node.js API was called in an unsupported manner, such as Buffer.write(string, encoding, offset[, length]).

[object Object]

Used generically to identify that an operation caused an out of memory condition.

[object Object]

The node:repl module was unable to parse data from the REPL history file.

[object Object]

Data could not be sent on a socket.

[object Object]

An attempt was made to close the process.stderr stream. By design, Node.js does not allow stdout or stderr streams to be closed by user code.

[object Object]

An attempt was made to close the process.stdout stream. By design, Node.js does not allow stdout or stderr streams to be closed by user code.

[object Object]

Used when an attempt is made to use a readable stream that has not implemented readable._read().

[object Object]

An error representing a failing lexer state.

[object Object]

An error representing a failing parser state. Additional information about the token causing the error is available via the cause property.

[object Object]

This error represents a failed TAP validation.

[object Object]

Used when a TLS renegotiation request has failed in a non-specific way.

[object Object]

A SharedArrayBuffer whose memory is not managed by the JavaScript engine or by Node.js was encountered during serialization. Such a SharedArrayBuffer cannot be serialized.

This can only happen when native addons create SharedArrayBuffers in "externalized" mode, or put existing SharedArrayBuffer into externalized mode.

[object Object]

An attempt was made to launch a Node.js process with an unknown stdin file type. This error is usually an indication of a bug within Node.js itself, although it is possible for user code to trigger it.

[object Object]

An attempt was made to launch a Node.js process with an unknown stdout or stderr file type. This error is usually an indication of a bug within Node.js itself, although it is possible for user code to trigger it.

[object Object]

The V8 BreakIterator API was used but the full ICU data set is not installed.

[object Object]

Used when a given value is out of the accepted range.

[object Object]

The linker function returned a module for which linking has failed.

[object Object]

The module must be successfully linked before instantiation.

[object Object]

The pathname used for the main script of a worker has an unknown file extension.

[object Object]

Used when an attempt is made to use a zlib object after it has already been closed.

[object Object]

[object Object]

[object Object]

The certificate is not yet valid: the notBefore date is after the current time.

[object Object]

The certificate has expired: the notAfter date is before the current time.

[object Object]

The certificate revocation list (CRL) has a future issue date.

[object Object]

The certificate revocation list (CRL) has expired.

[object Object]

The certificate has been revoked; it is on a certificate revocation list (CRL).

[object Object]

[object Object]

The issuer certificate of a looked up certificate could not be found. This normally means the list of trusted certificates is not complete.

[object Object]

The certificate’s issuer is not known. This is the case if the issuer is not included in the trusted certificate list.

[object Object]

The passed certificate is self-signed and the same certificate cannot be found in the list of trusted certificates.

[object Object]

The certificate’s issuer is not known. This is the case if the issuer is not included in the trusted certificate list.

[object Object]

The certificate chain length is greater than the maximum depth.

[object Object]

The CRL reference by the certificate could not be found.

[object Object]

No signatures could be verified because the chain contains only one certificate and it is not self signed.

[object Object]

The root certificate authority (CA) is not marked as trusted for the specified purpose.

[object Object]

[object Object]

A CA certificate is invalid. Either it is not a CA or its extensions are not consistent with the supplied purpose.

[object Object]

The basicConstraints pathlength parameter has been exceeded.

[object Object]

[object Object]

Certificate does not match provided name.

[object Object]

[object Object]

The supplied certificate cannot be used for the specified purpose.

[object Object]

The root CA is marked to reject the specified purpose.

[object Object]

[object Object]

The signature of the certificate is invalid.

[object Object]

The signature of the certificate revocation list (CRL) is invalid.

[object Object]

The certificate notBefore field contains an invalid time.

[object Object]

The certificate notAfter field contains an invalid time.

[object Object]

The CRL lastUpdate field contains an invalid time.

[object Object]

The CRL nextUpdate field contains an invalid time.

[object Object]

The certificate signature could not be decrypted. This means that the actual signature value could not be determined rather than it not matching the expected value, this is only meaningful for RSA keys.

[object Object]

The certificate revocation list (CRL) signature could not be decrypted: this means that the actual signature value could not be determined rather than it not matching the expected value.

[object Object]

The public key in the certificate SubjectPublicKeyInfo could not be read.

[object Object]

[object Object]

An error occurred trying to allocate memory. This should never happen.