Errors

Errors

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

Standard JavaScript errors such as {EvalError}, {SyntaxError}, {RangeError}, {ReferenceError}, {TypeError}, and {URIError}.
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 {Error} 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.

Error propagation and interception

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][try-catch] 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 {Promise} 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 {Promise}, 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.

```js 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.

js 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.

```js 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][domains] 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.

Class: `Error`

A generic JavaScript {Error} 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.

`new Error(message[, options])`

message {string}
options {Object}
cause {any} 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.

`Error.captureStackTrace(targetObject[, constructorOpt])`

targetObject {Object}
constructorOpt {Function}

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();

`Error.stackTraceLimit`

Type: {number}

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.

`error.cause`

Type: {any}

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)

`error.code`

Type: {string}

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.

`error.message`

Type: {string}

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

`error.stack`

Type: {string}

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 {Proxy}.

Class: `AssertionError`

Extends: {errors.Error}

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

Class: `DOMException`

Extends: {errors.Error}

The Web IDL {DOMException} class. These errors are thrown by web-platform APIs in Node.js such as [fetch()][], {AbortController}, {AbortSignal}, and Web Streams. For details, see also [Class: DOMException][] on the Globals page.

The [domException.name][] property identifies the type of the exception (for example, 'AbortError'). Unlike most errors in Node.js, the [domException.code][] property is a number that corresponds to a [legacy error code name][Web IDL error names] (for example, 20 for ABORT_ERR).

Node.js-specific APIs that support {AbortSignal} (such as [events.once()][]) throw a Node.js AbortError (a native {errors.Error} with name of 'AbortError' and code of ['ABORT_ERR'][ABORT_ERR]) rather than a {DOMException}. To identify abort errors in either case, checking err?.name === 'AbortError' is sufficient.

Class: `RangeError`

Extends: {errors.Error}

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.

Class: `ReferenceError`

Extends: {errors.Error}

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.

Class: `SyntaxError`

Extends: {errors.Error}

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.

Class: `SystemError`

Extends: {errors.Error}

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 {string} If present, the address to which a network connection failed
code {string} The string error code
dest {string} If present, the file path destination when reporting a file system error
errno {number} The system-provided error number
info {Object} If present, extra details about the error condition
message {string} A system-provided human-readable description of the error
path {string} If present, the file path when reporting a file system error
port {number} If present, the network connection port that is not available
syscall {string} The name of the system call that triggered the error

`error.address`

Type: {string}

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

`error.code`

Type: {string}

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

`error.dest`

Type: {string}

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

`error.errno`

Type: {number}

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)][].

`error.info`

Type: {Object}

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

`error.message`

Type: {string}

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

`error.path`

Type: {string}

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

`error.port`

Type: {number}

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

`error.syscall`

Type: {string}

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

Common system errors

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.

Class: `TypeError`

Extends {errors.Error}

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.

Exceptions vs. errors

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.

OpenSSL errors

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.

`error.opensslErrorStack`

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

`error.function`

The OpenSSL function the error originates in.

`error.library`

The OpenSSL library the error originates in.

`error.reason`

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

Node.js error codes

`ABORT_ERR`

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.

`ERR_ACCESS_DENIED`

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

`ERR_AMBIGUOUS_ARGUMENT`

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.

`ERR_ARG_NOT_ITERABLE`

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

`ERR_ASSERTION`

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.

`ERR_ASYNC_CALLBACK`

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

`ERR_ASYNC_LOADER_REQUEST_NEVER_SETTLED`

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

`ERR_ASYNC_TYPE`

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

`ERR_BROTLI_COMPRESSION_FAILED`

Data passed to a Brotli stream was not successfully compressed.

`ERR_BROTLI_INVALID_PARAM`

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

`ERR_BUFFER_CONTEXT_NOT_AVAILABLE`

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.

`ERR_BUFFER_OUT_OF_BOUNDS`

An operation outside the bounds of a Buffer was attempted.

`ERR_BUFFER_TOO_LARGE`

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

`ERR_CANNOT_WATCH_SIGINT`

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

`ERR_CHILD_CLOSED_BEFORE_REPLY`

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

`ERR_CHILD_PROCESS_IPC_REQUIRED`

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

`ERR_CHILD_PROCESS_STDIO_MAXBUFFER`

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.

`ERR_CLOSED_MESSAGE_PORT`

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

`ERR_CONSOLE_WRITABLE_STREAM`

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

`ERR_CONSTRUCT_CALL_INVALID`

A class constructor was called that is not callable.

`ERR_CONSTRUCT_CALL_REQUIRED`

A constructor for a class was called without new.

`ERR_CONTEXT_NOT_INITIALIZED`

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.

`ERR_CPU_PROFILE_ALREADY_STARTED`

The CPU profile with the given name is already started.

`ERR_CPU_PROFILE_NOT_STARTED`

The CPU profile with the given name is not started.

`ERR_CPU_PROFILE_TOO_MANY`

There are too many CPU profiles being collected.

`ERR_CRYPTO_ARGON2_NOT_SUPPORTED`

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

`ERR_CRYPTO_CUSTOM_ENGINE_NOT_SUPPORTED`

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.

`ERR_CRYPTO_ECDH_INVALID_FORMAT`

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

`ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY`

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.

`ERR_CRYPTO_ENGINE_UNKNOWN`

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

`ERR_CRYPTO_FIPS_FORCED`

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

`ERR_CRYPTO_FIPS_UNAVAILABLE`

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

`ERR_CRYPTO_HASH_FINALIZED`

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

`ERR_CRYPTO_HASH_UPDATE_FAILED`

[hash.update()][] failed for an unspecified reason.

`ERR_CRYPTO_INCOMPATIBLE_KEY`

The given crypto keys are incompatible with the attempted operation.

`ERR_CRYPTO_INCOMPATIBLE_KEY_OPTIONS`

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

`ERR_CRYPTO_INITIALIZATION_FAILED`

Initialization of the crypto subsystem failed.

`ERR_CRYPTO_INVALID_AUTH_TAG`

An invalid authentication tag was provided.

`ERR_CRYPTO_INVALID_COUNTER`

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

`ERR_CRYPTO_INVALID_CURVE`

An invalid elliptic-curve was provided.

`ERR_CRYPTO_INVALID_DIGEST`

An invalid [crypto digest algorithm][] was specified.

`ERR_CRYPTO_INVALID_IV`

An invalid initialization vector was provided.

`ERR_CRYPTO_INVALID_JWK`

An invalid JSON Web Key was provided.

`ERR_CRYPTO_INVALID_KEYLEN`

An invalid key length was provided.

`ERR_CRYPTO_INVALID_KEYPAIR`

An invalid key pair was provided.

`ERR_CRYPTO_INVALID_KEYTYPE`

An invalid key type was provided.

`ERR_CRYPTO_INVALID_KEY_OBJECT_TYPE`

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

`ERR_CRYPTO_INVALID_MAC`

An invalid MAC algorithm was specified.

`ERR_CRYPTO_INVALID_MESSAGELEN`

An invalid message length was provided.

`ERR_CRYPTO_INVALID_SCRYPT_PARAMS`

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

`ERR_CRYPTO_INVALID_STATE`

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

`ERR_CRYPTO_INVALID_TAG_LENGTH`

An invalid authentication tag length was provided.

`ERR_CRYPTO_JOB_INIT_FAILED`

Initialization of an asynchronous crypto operation failed.

`ERR_CRYPTO_JWK_UNSUPPORTED_CURVE`

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

`ERR_CRYPTO_JWK_UNSUPPORTED_KEY_TYPE`

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

`ERR_CRYPTO_KEM_NOT_SUPPORTED`

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

`ERR_CRYPTO_MAC_FINALIZED`

An operation was attempted on a Mac object after finalization was attempted or an underlying MAC update failed.

`ERR_CRYPTO_MAC_NOT_SUPPORTED`

Node.js was built without support for the OpenSSL EVP_MAC API.

`ERR_CRYPTO_MAC_UPDATE_FAILED`

[mac.update()][] failed for an unspecified reason.

`ERR_CRYPTO_OPERATION_FAILED`

A crypto operation failed for an otherwise unspecified reason.

`ERR_CRYPTO_PBKDF2_ERROR`

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

`ERR_CRYPTO_SCRYPT_NOT_SUPPORTED`

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

`ERR_CRYPTO_SIGN_KEY_REQUIRED`

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

`ERR_CRYPTO_TIMING_SAFE_EQUAL_LENGTH`

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

`ERR_CRYPTO_UNKNOWN_CIPHER`

An unknown cipher was specified.

`ERR_CRYPTO_UNKNOWN_DH_GROUP`

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

`ERR_CRYPTO_UNSUPPORTED_OPERATION`

An attempt to invoke an unsupported crypto operation was made.

`ERR_DEBUGGER_ERROR`

An error occurred with the [debugger][].

`ERR_DEBUGGER_STARTUP_ERROR`

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

`ERR_DIR_CLOSED`

The [fs.Dir][] was previously closed.

`ERR_DIR_CONCURRENT_OPERATION`

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

`ERR_DLOPEN_DISABLED`

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

`ERR_DLOPEN_FAILED`

A call to process.dlopen() failed.

`ERR_DNS_SET_SERVERS_FAILED`

c-ares failed to set the DNS server.

`ERR_DOMAIN_CALLBACK_NOT_AVAILABLE`

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.

`ERR_DOMAIN_CANNOT_SET_UNCAUGHT_EXCEPTION_CAPTURE`

[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.

`ERR_DUPLICATE_STARTUP_SNAPSHOT_MAIN_FUNCTION`

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

`ERR_ENCODING_INVALID_ENCODED_DATA`

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

`ERR_ENCODING_NOT_SUPPORTED`

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

`ERR_EVAL_ESM_CANNOT_PRINT`

--print cannot be used with ESM input.

`ERR_EVENT_RECURSION`

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

`ERR_EXECUTION_ENVIRONMENT_NOT_AVAILABLE`

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.

`ERR_FALSY_VALUE_REJECTION`

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

`ERR_FEATURE_UNAVAILABLE_ON_PLATFORM`

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

`ERR_FFI_CALL_FAILED`

A low-level FFI call failed.

`ERR_FFI_INVALID_POINTER`

An invalid pointer was passed to an FFI operation.

`ERR_FFI_LIBRARY_CLOSED`

An operation was attempted on an FFI dynamic library after it was closed.

`ERR_FS_CP_DIR_TO_NON_DIR`

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

`ERR_FS_CP_EEXIST`

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

`ERR_FS_CP_EINVAL`

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

`ERR_FS_CP_FIFO_PIPE`

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

`ERR_FS_CP_NON_DIR_TO_DIR`

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

`ERR_FS_CP_SOCKET`

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

`ERR_FS_CP_SYMLINK_TO_SUBDIRECTORY`

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

`ERR_FS_CP_UNKNOWN`

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

`ERR_FS_EISDIR`

Path is a directory.

`ERR_FS_FILE_TOO_LARGE`

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.

`ERR_FS_WATCH_QUEUE_OVERFLOW`

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

`ERR_HTTP2_ALTSVC_INVALID_ORIGIN`

HTTP/2 ALTSVC frames require a valid origin.

`ERR_HTTP2_ALTSVC_LENGTH`

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

`ERR_HTTP2_CONNECT_AUTHORITY`

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

`ERR_HTTP2_CONNECT_PATH`

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

`ERR_HTTP2_CONNECT_SCHEME`

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

`ERR_HTTP2_ERROR`

A non-specific HTTP/2 error has occurred.

`ERR_HTTP2_GOAWAY_SESSION`

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

`ERR_HTTP2_HEADERS_AFTER_RESPOND`

Additional headers were specified after an HTTP/2 response was initiated.

`ERR_HTTP2_HEADERS_SENT`

An attempt was made to send multiple response headers.

`ERR_HTTP2_HEADER_SINGLE_VALUE`

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

`ERR_HTTP2_INFO_STATUS_NOT_ALLOWED`

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

`ERR_HTTP2_INVALID_CONNECTION_HEADERS`

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

`ERR_HTTP2_INVALID_HEADER_VALUE`

An invalid HTTP/2 header value was specified.

`ERR_HTTP2_INVALID_INFO_STATUS`

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

`ERR_HTTP2_INVALID_ORIGIN`

HTTP/2 ORIGIN frames requir

（本文超出站点单文档体积上限，已截断）

Errors

Errors

Error propagation and interception

Class: Error

new Error(message[, options])

Error.captureStackTrace(targetObject[, constructorOpt])

Error.stackTraceLimit

error.cause

error.code

error.message

error.stack

Class: AssertionError

Class: DOMException

Class: RangeError

Class: ReferenceError

Class: SyntaxError

Class: SystemError

error.address

error.code

error.dest

error.errno

error.info

error.message

error.path

error.port

error.syscall

Common system errors

Class: TypeError

Exceptions vs. errors

OpenSSL errors

error.opensslErrorStack

error.function

error.library

error.reason

Node.js error codes

ABORT_ERR

ERR_ACCESS_DENIED

ERR_AMBIGUOUS_ARGUMENT

ERR_ARG_NOT_ITERABLE

ERR_ASSERTION

ERR_ASYNC_CALLBACK

ERR_ASYNC_LOADER_REQUEST_NEVER_SETTLED

ERR_ASYNC_TYPE

ERR_BROTLI_COMPRESSION_FAILED

ERR_BROTLI_INVALID_PARAM

ERR_BUFFER_CONTEXT_NOT_AVAILABLE

ERR_BUFFER_OUT_OF_BOUNDS

ERR_BUFFER_TOO_LARGE

ERR_CANNOT_WATCH_SIGINT

ERR_CHILD_CLOSED_BEFORE_REPLY

ERR_CHILD_PROCESS_IPC_REQUIRED

ERR_CHILD_PROCESS_STDIO_MAXBUFFER

ERR_CLOSED_MESSAGE_PORT

ERR_CONSOLE_WRITABLE_STREAM

ERR_CONSTRUCT_CALL_INVALID

ERR_CONSTRUCT_CALL_REQUIRED

ERR_CONTEXT_NOT_INITIALIZED

ERR_CPU_PROFILE_ALREADY_STARTED

ERR_CPU_PROFILE_NOT_STARTED

ERR_CPU_PROFILE_TOO_MANY

ERR_CRYPTO_ARGON2_NOT_SUPPORTED

ERR_CRYPTO_CUSTOM_ENGINE_NOT_SUPPORTED

ERR_CRYPTO_ECDH_INVALID_FORMAT

ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY

ERR_CRYPTO_ENGINE_UNKNOWN

ERR_CRYPTO_FIPS_FORCED

ERR_CRYPTO_FIPS_UNAVAILABLE

ERR_CRYPTO_HASH_FINALIZED

ERR_CRYPTO_HASH_UPDATE_FAILED

ERR_CRYPTO_INCOMPATIBLE_KEY

ERR_CRYPTO_INCOMPATIBLE_KEY_OPTIONS

ERR_CRYPTO_INITIALIZATION_FAILED

ERR_CRYPTO_INVALID_AUTH_TAG

ERR_CRYPTO_INVALID_COUNTER

ERR_CRYPTO_INVALID_CURVE

ERR_CRYPTO_INVALID_DIGEST

ERR_CRYPTO_INVALID_IV

ERR_CRYPTO_INVALID_JWK

ERR_CRYPTO_INVALID_KEYLEN

ERR_CRYPTO_INVALID_KEYPAIR

Class: `Error`

`new Error(message[, options])`

`Error.captureStackTrace(targetObject[, constructorOpt])`

`Error.stackTraceLimit`

`error.cause`

`error.code`

`error.message`

`error.stack`

Class: `AssertionError`

Class: `DOMException`

Class: `RangeError`

Class: `ReferenceError`

Class: `SyntaxError`

Class: `SystemError`

`error.address`

`error.code`

`error.dest`

`error.errno`

`error.info`

`error.message`

`error.path`

`error.port`

`error.syscall`

Class: `TypeError`

`error.opensslErrorStack`

`error.function`

`error.library`

`error.reason`

`ABORT_ERR`

`ERR_ACCESS_DENIED`

`ERR_AMBIGUOUS_ARGUMENT`

`ERR_ARG_NOT_ITERABLE`

`ERR_ASSERTION`

`ERR_ASYNC_CALLBACK`

`ERR_ASYNC_LOADER_REQUEST_NEVER_SETTLED`

`ERR_ASYNC_TYPE`

`ERR_BROTLI_COMPRESSION_FAILED`

`ERR_BROTLI_INVALID_PARAM`

`ERR_BUFFER_CONTEXT_NOT_AVAILABLE`

`ERR_BUFFER_OUT_OF_BOUNDS`

`ERR_BUFFER_TOO_LARGE`

`ERR_CANNOT_WATCH_SIGINT`

`ERR_CHILD_CLOSED_BEFORE_REPLY`

`ERR_CHILD_PROCESS_IPC_REQUIRED`

`ERR_CHILD_PROCESS_STDIO_MAXBUFFER`

`ERR_CLOSED_MESSAGE_PORT`

`ERR_CONSOLE_WRITABLE_STREAM`

`ERR_CONSTRUCT_CALL_INVALID`

`ERR_CONSTRUCT_CALL_REQUIRED`

`ERR_CONTEXT_NOT_INITIALIZED`

`ERR_CPU_PROFILE_ALREADY_STARTED`

`ERR_CPU_PROFILE_NOT_STARTED`

`ERR_CPU_PROFILE_TOO_MANY`

`ERR_CRYPTO_ARGON2_NOT_SUPPORTED`

`ERR_CRYPTO_CUSTOM_ENGINE_NOT_SUPPORTED`

`ERR_CRYPTO_ECDH_INVALID_FORMAT`

`ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY`

`ERR_CRYPTO_ENGINE_UNKNOWN`

`ERR_CRYPTO_FIPS_FORCED`

`ERR_CRYPTO_FIPS_UNAVAILABLE`

`ERR_CRYPTO_HASH_FINALIZED`

`ERR_CRYPTO_HASH_UPDATE_FAILED`

`ERR_CRYPTO_INCOMPATIBLE_KEY`

`ERR_CRYPTO_INCOMPATIBLE_KEY_OPTIONS`

`ERR_CRYPTO_INITIALIZATION_FAILED`

`ERR_CRYPTO_INVALID_AUTH_TAG`

`ERR_CRYPTO_INVALID_COUNTER`

`ERR_CRYPTO_INVALID_CURVE`

`ERR_CRYPTO_INVALID_DIGEST`

`ERR_CRYPTO_INVALID_IV`

`ERR_CRYPTO_INVALID_JWK`

`ERR_CRYPTO_INVALID_KEYLEN`

`ERR_CRYPTO_INVALID_KEYPAIR`

`ERR_CRYPTO_INVALID_KEYTYPE`

`ERR_CRYPTO_INVALID_KEY_OBJECT_TYPE`

`ERR_CRYPTO_INVALID_MAC`

`ERR_CRYPTO_INVALID_MESSAGELEN`

`ERR_CRYPTO_INVALID_SCRYPT_PARAMS`

`ERR_CRYPTO_INVALID_STATE`

`ERR_CRYPTO_INVALID_TAG_LENGTH`