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Node.js v9.10.0 Documentation
Table of Contents
- Deprecated APIs
- Un-deprecation
- List of Deprecated APIs
- DEP0001: http.OutgoingMessage.prototype.flush
- DEP0002: require('_linklist')
- DEP0003: _writableState.buffer
- DEP0004: CryptoStream.prototype.readyState
- DEP0005: Buffer() constructor
- DEP0006: child_process options.customFds
- DEP0007: Replace cluster worker.suicide with worker.exitedAfterDisconnect
- DEP0008: require('constants')
- DEP0009: crypto.pbkdf2 without digest
- DEP0010: crypto.createCredentials
- DEP0011: crypto.Credentials
- DEP0012: Domain.dispose
- DEP0013: fs asynchronous function without callback
- DEP0014: fs.read legacy String interface
- DEP0015: fs.readSync legacy String interface
- DEP0016: GLOBAL/root
- DEP0017: Intl.v8BreakIterator
- DEP0018: Unhandled promise rejections
- DEP0019: require('.') resolved outside directory
- DEP0020: Server.connections
- DEP0021: Server.listenFD
- DEP0022: os.tmpDir()
- DEP0023: os.getNetworkInterfaces()
- DEP0024: REPLServer.prototype.convertToContext()
- DEP0025: require('sys')
- DEP0026: util.print()
- DEP0027: util.puts()
- DEP0028: util.debug()
- DEP0029: util.error()
- DEP0030: SlowBuffer
- DEP0031: ecdh.setPublicKey()
- DEP0032: domain module
- DEP0033: EventEmitter.listenerCount()
- DEP0034: fs.exists(path, callback)
- DEP0035: fs.lchmod(path, mode, callback)
- DEP0036: fs.lchmodSync(path, mode)
- DEP0037: fs.lchown(path, uid, gid, callback)
- DEP0038: fs.lchownSync(path, uid, gid)
- DEP0039: require.extensions
- DEP0040: punycode module
- DEP0041: NODE_REPL_HISTORY_FILE environment variable
- DEP0042: tls.CryptoStream
- DEP0043: tls.SecurePair
- DEP0044: util.isArray()
- DEP0045: util.isBoolean()
- DEP0046: util.isBuffer()
- DEP0047: util.isDate()
- DEP0048: util.isError()
- DEP0049: util.isFunction()
- DEP0050: util.isNull()
- DEP0051: util.isNullOrUndefined()
- DEP0052: util.isNumber()
- DEP0053 util.isObject()
- DEP0054: util.isPrimitive()
- DEP0055: util.isRegExp()
- DEP0056: util.isString()
- DEP0057: util.isSymbol()
- DEP0058: util.isUndefined()
- DEP0059: util.log()
- DEP0060: util._extend()
- DEP0061: fs.SyncWriteStream
- DEP0062: node --debug
- DEP0063: ServerResponse.prototype.writeHeader()
- DEP0064: tls.createSecurePair()
- DEP0065: repl.REPL_MODE_MAGIC and NODE_REPL_MODE=magic
- DEP0066: outgoingMessage._headers, outgoingMessage._headerNames
- DEP0067: OutgoingMessage.prototype._renderHeaders
- DEP0068: node debug
- DEP0069: vm.runInDebugContext(string)
- DEP0070: async_hooks.currentId()
- DEP0071: async_hooks.triggerId()
- DEP0072: async_hooks.AsyncResource.triggerId()
- DEP0073: Several internal properties of net.Server
- DEP0074: REPLServer.bufferedCommand
- DEP0075: REPLServer.parseREPLKeyword()
- DEP0076: tls.parseCertString()
- DEP0077: Module._debug()
- DEP0078: REPLServer.turnOffEditorMode()
- DEP0079: Custom inspection function on Objects via .inspect()
- DEP0080: path._makeLong()
- DEP0081: fs.truncate() using a file descriptor
- DEP0082: REPLServer.prototype.memory()
- DEP0083: Disabling ECDH by setting ecdhCurve to false
- DEP0085: AsyncHooks Sensitive API
- DEP0086: Remove runInAsyncIdScope
- DEP0089: require('assert')
- DEP0098: AsyncHooks Embedder AsyncResource.emit<Before,After> APIs
Deprecated APIs#
Node.js may deprecate APIs when either: (a) use of the API is considered to be unsafe, (b) an improved alternative API has been made available, or (c) breaking changes to the API are expected in a future major release.
Node.js utilizes three kinds of Deprecations:
- Documentation-only
- Runtime
- End-of-Life
A Documentation-only deprecation is one that is expressed only within the
Node.js API docs. These generate no side-effects while running Node.js.
Some Documentation-only deprecations trigger a runtime warning when launched
with [--pending-deprecation][] flag (or its alternative,
NODE_PENDING_DEPRECATION=1 environment variable), similarly to Runtime
deprecations below. Documentation-only deprecations that support that flag
are explicitly labeled as such in the
list of Deprecated APIs.
A Runtime deprecation will, by default, generate a process warning that will
be printed to stderr the first time the deprecated API is used. When the
--throw-deprecation command-line flag is used, a Runtime deprecation will
cause an error to be thrown.
An End-of-Life deprecation is used to identify code that either has been removed or will soon be removed from Node.js.
Un-deprecation#
From time-to-time the deprecation of an API may be reversed. Such action may happen in either a semver-minor or semver-major release. In such situations, this document will be updated with information relevant to the decision. However, the deprecation identifier will not be modified.
List of Deprecated APIs#
DEP0001: http.OutgoingMessage.prototype.flush#
Type: Runtime
The OutgoingMessage.prototype.flush() method is deprecated. Use
OutgoingMessage.prototype.flushHeaders() instead.
DEP0002: require('_linklist')#
Type: End-of-Life
The _linklist module is deprecated. Please use a userland alternative.
DEP0003: _writableState.buffer#
Type: Runtime
The _writableState.buffer property is deprecated. Use the
_writableState.getBuffer() method instead.
DEP0004: CryptoStream.prototype.readyState#
Type: Documentation-only
The CryptoStream.prototype.readyState property is deprecated and should not
be used.
DEP0005: Buffer() constructor#
Type: Documentation-only (supports [--pending-deprecation][])
The Buffer() function and new Buffer() constructor are deprecated due to
API usability issues that can potentially lead to accidental security issues.
As an alternative, use of the following methods of constructing Buffer objects
is strongly recommended:
Buffer.alloc(size[, fill[, encoding]])- Create aBufferwith initialized memory.Buffer.allocUnsafe(size)- Create aBufferwith uninitialized memory.Buffer.allocUnsafeSlow(size)- Create aBufferwith uninitialized memory.Buffer.from(array)- Create aBufferwith a copy ofarrayBuffer.from(arrayBuffer[, byteOffset[, length]])- Create aBufferthat wraps the givenarrayBuffer.Buffer.from(buffer)- Create aBufferthat copiesbuffer.Buffer.from(string[, encoding])- Create aBufferthat copiesstring.
DEP0006: child_process options.customFds#
Type: Runtime
Within the child_process module's spawn(), fork(), and exec()
methods, the options.customFds option is deprecated. The options.stdio
option should be used instead.
DEP0007: Replace cluster worker.suicide with worker.exitedAfterDisconnect#
Type: End-of-Life
In an earlier version of the Node.js cluster, a boolean property with the name
suicide was added to the Worker object. The intent of this property was to
provide an indication of how and why the Worker instance exited. In Node.js
6.0.0, the old property was deprecated and replaced with a new
worker.exitedAfterDisconnect property. The old property name did not
precisely describe the actual semantics and was unnecessarily emotion-laden.
DEP0008: require('constants')#
Type: Documentation-only
The constants module has been deprecated. When requiring access to constants
relevant to specific Node.js builtin modules, developers should instead refer
to the constants property exposed by the relevant module. For instance,
require('fs').constants and require('os').constants.
DEP0009: crypto.pbkdf2 without digest#
Type: End-of-life
Use of the crypto.pbkdf2() API without specifying a digest was deprecated
in Node.js 6.0 because the method defaulted to using the non-recommended
'SHA1' digest. Previously, a deprecation warning was printed. Starting in
Node.js 8.0.0, calling crypto.pbkdf2() or crypto.pbkdf2Sync() with an
undefined digest will throw a TypeError.
DEP0010: crypto.createCredentials#
Type: Runtime
The crypto.createCredentials() API is deprecated. Please use
tls.createSecureContext() instead.
DEP0011: crypto.Credentials#
Type: Runtime
The crypto.Credentials class is deprecated. Please use tls.SecureContext
instead.
DEP0012: Domain.dispose#
Type: End-of-Life
Domain.dispose() is removed. Recover from failed I/O actions
explicitly via error event handlers set on the domain instead.
DEP0013: fs asynchronous function without callback#
Type: Runtime
Calling an asynchronous function without a callback is deprecated.
DEP0014: fs.read legacy String interface#
Type: End-of-Life
The fs.read() legacy String interface is deprecated. Use the Buffer API as
mentioned in the documentation instead.
DEP0015: fs.readSync legacy String interface#
Type: End-of-Life
The fs.readSync() legacy String interface is deprecated. Use the Buffer
API as mentioned in the documentation instead.
DEP0016: GLOBAL/root#
Type: Runtime
The GLOBAL and root aliases for the global property have been deprecated
and should no longer be used.
DEP0017: Intl.v8BreakIterator#
Type: End-of-Life
Intl.v8BreakIterator was a non-standard extension and has been removed.
See Intl.Segmenter.
DEP0018: Unhandled promise rejections#
Type: Runtime
Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
DEP0019: require('.') resolved outside directory#
Type: Runtime
In certain cases, require('.') may resolve outside the package directory.
This behavior is deprecated and will be removed in a future major Node.js
release.
DEP0020: Server.connections#
Type: Runtime
The Server.connections property is deprecated. Please use the
Server.getConnections() method instead.
DEP0021: Server.listenFD#
Type: Runtime
The Server.listenFD() method is deprecated. Please use
Server.listen({fd: <number>}) instead.
DEP0022: os.tmpDir()#
Type: Runtime
The os.tmpDir() API is deprecated. Please use os.tmpdir() instead.
DEP0023: os.getNetworkInterfaces()#
Type: Runtime
The os.getNetworkInterfaces() method is deprecated. Please use the
os.networkInterfaces property instead.
DEP0024: REPLServer.prototype.convertToContext()#
Type: End-of-Life
The REPLServer.prototype.convertToContext() API is deprecated and should
not be used.
DEP0025: require('sys')#
Type: Runtime
The sys module is deprecated. Please use the util module instead.
DEP0026: util.print()#
Type: Runtime
The util.print() API is deprecated. Please use console.log()
instead.
DEP0027: util.puts()#
Type: Runtime
The util.puts() API is deprecated. Please use console.log() instead.
DEP0028: util.debug()#
Type: Runtime
The util.debug() API is deprecated. Please use console.error()
instead.
DEP0029: util.error()#
Type: Runtime
The util.error() API is deprecated. Please use console.error()
instead.
DEP0030: SlowBuffer#
Type: Documentation-only
The SlowBuffer class has been deprecated. Please use
Buffer.allocUnsafeSlow(size) instead.
DEP0031: ecdh.setPublicKey()#
Type: Documentation-only
The ecdh.setPublicKey() method is now deprecated as its inclusion in the
API is not useful.
DEP0032: domain module#
Type: Documentation-only
The domain module is deprecated and should not be used.
DEP0033: EventEmitter.listenerCount()#
Type: Documentation-only
The EventEmitter.listenerCount(emitter, eventName) API has been
deprecated. Please use emitter.listenerCount(eventName) instead.
DEP0034: fs.exists(path, callback)#
Type: Documentation-only
The fs.exists(path, callback) API has been deprecated. Please use
fs.stat() or fs.access() instead.
DEP0035: fs.lchmod(path, mode, callback)#
Type: Documentation-only
The fs.lchmod(path, mode, callback) API has been deprecated.
DEP0036: fs.lchmodSync(path, mode)#
Type: Documentation-only
The fs.lchmodSync(path, mode) API has been deprecated.
DEP0037: fs.lchown(path, uid, gid, callback)#
Type: Documentation-only
The fs.lchown(path, uid, gid, callback) API has been deprecated.
DEP0038: fs.lchownSync(path, uid, gid)#
Type: Documentation-only
The fs.lchownSync(path, uid, gid) API has been deprecated.
DEP0039: require.extensions#
Type: Documentation-only
The require.extensions property has been deprecated.
DEP0040: punycode module#
Type: Documentation-only
The punycode module has been deprecated. Please use a userland alternative
instead.
DEP0041: NODE_REPL_HISTORY_FILE environment variable#
Type: Documentation-only
The NODE_REPL_HISTORY_FILE environment variable has been deprecated.
DEP0042: tls.CryptoStream#
Type: Documentation-only
The tls.CryptoStream class has been deprecated. Please use
tls.TLSSocket instead.
DEP0043: tls.SecurePair#
Type: Documentation-only
The tls.SecurePair class has been deprecated. Please use
tls.TLSSocket instead.
DEP0044: util.isArray()#
Type: Documentation-only
The util.isArray() API has been deprecated. Please use Array.isArray()
instead.
DEP0045: util.isBoolean()#
Type: Documentation-only
The util.isBoolean() API has been deprecated.
DEP0046: util.isBuffer()#
Type: Documentation-only
The util.isBuffer() API has been deprecated. Please use
Buffer.isBuffer() instead.
DEP0047: util.isDate()#
Type: Documentation-only
The util.isDate() API has been deprecated.
DEP0048: util.isError()#
Type: Documentation-only
The util.isError() API has been deprecated.
DEP0049: util.isFunction()#
Type: Documentation-only
The util.isFunction() API has been deprecated.
DEP0050: util.isNull()#
Type: Documentation-only
The util.isNull() API has been deprecated.
DEP0051: util.isNullOrUndefined()#
Type: Documentation-only
The util.isNullOrUndefined() API has been deprecated.
DEP0052: util.isNumber()#
Type: Documentation-only
The util.isNumber() API has been deprecated.
DEP0053 util.isObject()#
Type: Documentation-only
The util.isObject() API has been deprecated.
DEP0054: util.isPrimitive()#
Type: Documentation-only
The util.isPrimitive() API has been deprecated.
DEP0055: util.isRegExp()#
Type: Documentation-only
The util.isRegExp() API has been deprecated.
DEP0056: util.isString()#
Type: Documentation-only
The util.isString() API has been deprecated.
DEP0057: util.isSymbol()#
Type: Documentation-only
The util.isSymbol() API has been deprecated.
DEP0058: util.isUndefined()#
Type: Documentation-only
The util.isUndefined() API has been deprecated.
DEP0059: util.log()#
Type: Documentation-only
The util.log() API has been deprecated.
DEP0060: util._extend()#
Type: Documentation-only
The util._extend() API has been deprecated.
DEP0061: fs.SyncWriteStream#
Type: Runtime
The fs.SyncWriteStream class was never intended to be a publicly accessible
API. No alternative API is available. Please use a userland alternative.
DEP0062: node --debug#
Type: Runtime
--debug activates the legacy V8 debugger interface, which has been removed as
of V8 5.8. It is replaced by Inspector which is activated with --inspect
instead.
DEP0063: ServerResponse.prototype.writeHeader()#
Type: Documentation-only
The http module ServerResponse.prototype.writeHeader() API has been
deprecated. Please use ServerResponse.prototype.writeHead() instead.
The ServerResponse.prototype.writeHeader() method was never documented as an
officially supported API.
DEP0064: tls.createSecurePair()#
Type: Runtime
The tls.createSecurePair() API was deprecated in documentation in Node.js
0.11.3. Users should use tls.Socket instead.
DEP0065: repl.REPL_MODE_MAGIC and NODE_REPL_MODE=magic#
Type: Documentation-only
The repl module's REPL_MODE_MAGIC constant, used for replMode option, has
been deprecated. Its behavior has been functionally identical to that of
REPL_MODE_SLOPPY since Node.js v6.0.0, when V8 5.0 was imported. Please use
REPL_MODE_SLOPPY instead.
The NODE_REPL_MODE environment variable is used to set the underlying
replMode of an interactive node session. Its default value, magic, is
similarly deprecated in favor of sloppy.
DEP0066: outgoingMessage._headers, outgoingMessage._headerNames#
Type: Documentation-only
The http module outgoingMessage._headers and outgoingMessage._headerNames
properties have been deprecated. Please instead use one of the public methods
(e.g. outgoingMessage.getHeader(), outgoingMessage.getHeaders(),
outgoingMessage.getHeaderNames(), outgoingMessage.hasHeader(),
outgoingMessage.removeHeader(), outgoingMessage.setHeader()) for working
with outgoing headers.
The outgoingMessage._headers and outgoingMessage._headerNames properties
were never documented as officially supported properties.
DEP0067: OutgoingMessage.prototype._renderHeaders#
Type: Documentation-only
The http module OutgoingMessage.prototype._renderHeaders() API has been
deprecated.
The OutgoingMessage.prototype._renderHeaders property was never documented as
an officially supported API.
DEP0068: node debug#
Type: Runtime
node debug corresponds to the legacy CLI debugger which has been replaced with
a V8-inspector based CLI debugger available through node inspect.
DEP0069: vm.runInDebugContext(string)#
Type: Runtime
The DebugContext will be removed in V8 soon and will not be available in Node 10+.
DebugContext was an experimental API.
DEP0070: async_hooks.currentId()#
Type: End-of-Life
async_hooks.currentId() was renamed to async_hooks.executionAsyncId() for
clarity.
This change was made while async_hooks was an experimental API.
DEP0071: async_hooks.triggerId()#
Type: End-of-Life
async_hooks.triggerId() was renamed to async_hooks.triggerAsyncId() for
clarity.
This change was made while async_hooks was an experimental API.
DEP0072: async_hooks.AsyncResource.triggerId()#
Type: End-of-Life
async_hooks.AsyncResource.triggerId() was renamed to
async_hooks.AsyncResource.triggerAsyncId() for clarity.
This change was made while async_hooks was an experimental API.
DEP0073: Several internal properties of net.Server#
Type: Runtime
Accessing several internal, undocumented properties of net.Server instances
with inappropriate names has been deprecated.
As the original API was undocumented and not generally useful for non-internal code, no replacement API is provided.
DEP0074: REPLServer.bufferedCommand#
Type: Runtime
The REPLServer.bufferedCommand property was deprecated in favor of
REPLServer.clearBufferedCommand().
DEP0075: REPLServer.parseREPLKeyword()#
Type: Runtime
REPLServer.parseREPLKeyword() was removed from userland visibility.
DEP0076: tls.parseCertString()#
Type: Runtime
tls.parseCertString() is a trivial parsing helper that was made public by
mistake. This function can usually be replaced with:
const querystring = require('querystring');
querystring.parse(str, '\n', '=');
This function is not completely equivalent to querystring.parse(). One
difference is that querystring.parse() does url decoding:
> querystring.parse('%E5%A5%BD=1', '\n', '=');
{ '好': '1' }
> tls.parseCertString('%E5%A5%BD=1');
{ '%E5%A5%BD': '1' }
DEP0077: Module._debug()#
Type: Runtime
Module._debug() has been deprecated.
The Module._debug() function was never documented as an officially supported
API.
DEP0078: REPLServer.turnOffEditorMode()#
Type: Runtime
REPLServer.turnOffEditorMode() was removed from userland visibility.
DEP0079: Custom inspection function on Objects via .inspect()#
Type: Documentation-only
Using a property named inspect on an object to specify a custom inspection
function for util.inspect() is deprecated. Use util.inspect.custom
instead. For backwards compatibility with Node.js prior to version 6.4.0, both
may be specified.
DEP0080: path._makeLong()#
Type: Documentation-only
The internal path._makeLong() was not intended for public use. However,
userland modules have found it useful. The internal API has been deprecated
and replaced with an identical, public path.toNamespacedPath() method.
DEP0081: fs.truncate() using a file descriptor#
Type: Runtime
fs.truncate() fs.truncateSync() usage with a file descriptor has been
deprecated. Please use fs.ftruncate() or fs.ftruncateSync() to work with
file descriptors.
DEP0082: REPLServer.prototype.memory()#
Type: Runtime
REPLServer.prototype.memory() is a function only necessary for the
internal mechanics of the REPLServer itself, and is therefore not
necessary in user space.
DEP0083: Disabling ECDH by setting ecdhCurve to false#
Type: Runtime
The ecdhCurve option to tls.createSecureContext() and tls.TLSSocket could
be set to false to disable ECDH entirely on the server only. This mode is
deprecated in preparation for migrating to OpenSSL 1.1.0 and consistency with
the client. Use the ciphers parameter instead.
DEP0085: AsyncHooks Sensitive API#
Type: Runtime
The AsyncHooks Sensitive API was never documented and had various of minor
issues, see https://github.com/nodejs/node/issues/15572. Use the AsyncResource
API instead.
DEP0086: Remove runInAsyncIdScope#
Type: Runtime
runInAsyncIdScope doesn't emit the before or after event and can thus
cause a lot of issues. See https://github.com/nodejs/node/issues/14328 for more
details.
DEP0089: require('assert')#
Type: Documentation-only
Importing assert directly is not recommended as the exposed functions will use
loose equality checks. Use require('assert').strict instead. The API is the
same as the legacy assert but it will always use strict equality checks.
DEP0098: AsyncHooks Embedder AsyncResource.emit<Before,After> APIs#
Type: Runtime
The embedded API provided by AsyncHooks exposes emit<Before,After> methods which are very easy to use incorrectly which can lead to unrecoverable errors.
Use asyncResource.runInAsyncScope() API instead which provides a much
safer, and more convenient, alternative. See
https://github.com/nodejs/node/pull/18513 for more details.