# Deprecated APIs
Node.js may deprecate APIs for any of the following reasons:
* Use of the API is unsafe.
* An improved alternative API is available.
* 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](#deprecations_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 when functionality is or will soon be removed
from Node.js.
## Revoking deprecations
Occasionally, the deprecation of an API may be reversed. 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: End-of-Life
The `CryptoStream.prototype.readyState` property was removed.
### DEP0005: Buffer() constructor
Type: Runtime (supports [`--pending-deprecation`][])
The `Buffer()` function and `new Buffer()` constructor are deprecated due to
API usability issues that can lead to accidental security issues.
As an alternative, use one of the following methods of constructing `Buffer`
objects:
* [`Buffer.alloc(size[, fill[, encoding]])`][alloc]: Create a `Buffer` with
*initialized* memory.
* [`Buffer.allocUnsafe(size)`][alloc_unsafe_size]: Create a `Buffer` with
*uninitialized* memory.
* [`Buffer.allocUnsafeSlow(size)`][]: Create a `Buffer` with *uninitialized*
memory.
* [`Buffer.from(array)`][]: Create a `Buffer` with a copy of `array`
* [`Buffer.from(arrayBuffer[, byteOffset[, length]])`][from_arraybuffer] -
Create a `Buffer` that wraps the given `arrayBuffer`.
* [`Buffer.from(buffer)`][]: Create a `Buffer` that copies `buffer`.
* [`Buffer.from(string[, encoding])`][from_string_encoding]: Create a `Buffer`
that copies `string`.
Without `--pending-deprecation`, runtime warnings occur only for code not in
`node_modules`. This means there will not be deprecation warnings for
`Buffer()` usage in dependencies. With `--pending-deprecation`, a runtime
warning results no matter where the `Buffer()` usage occurs.
### DEP0006: child\_process options.customFds
Type: End-of-Life
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 is 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: Runtime
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
`digest` set to `undefined` will throw a `TypeError`.
Beginning in Node.js v11.0.0, calling these functions with `digest` set to
`null` will print a deprecation warning to align with the behavior when `digest`
is `undefined`.
### DEP0010: crypto.createCredentials
Type: End-of-Life
The `crypto.createCredentials()` API was removed. Please use
[`tls.createSecureContext()`][] instead.
### DEP0011: crypto.Credentials
Type: End-of-Life
The `crypto.Credentials` class was removed. Please use [`tls.SecureContext`][]
instead.
### DEP0012: Domain.dispose
Type: End-of-Life
`Domain.dispose()` has been removed. Recover from failed I/O actions
explicitly via error event handlers set on the domain instead.
### DEP0013: fs asynchronous function without callback
Type: End-of-Life
Calling an asynchronous function without a callback throws a `TypeError`
in Node.js 10.0.0 onwards. See .
### 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 are 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`](https://github.com/tc39/proposal-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: End-of-Life
In certain cases, `require('.')` could resolve outside the package directory.
This behavior has been removed.
### DEP0020: Server.connections
Type: Runtime
The [`Server.connections`][] property is deprecated. Please use the
[`Server.getConnections()`][] method instead.
### DEP0021: Server.listenFD
Type: End-of-Life
The `Server.listenFD()` method was deprecated and removed. Please use
[`Server.listen({fd: })`][] instead.
### DEP0022: os.tmpDir()
Type: Runtime
The `os.tmpDir()` API is deprecated. Please use [`os.tmpdir()`][] instead.
### DEP0023: os.getNetworkInterfaces()
Type: End-of-Life
The `os.getNetworkInterfaces()` method is deprecated. Please use the
[`os.networkInterfaces()`][] method instead.
### DEP0024: REPLServer.prototype.convertToContext()
Type: End-of-Life
The `REPLServer.prototype.convertToContext()` API has been removed.
### DEP0025: require('sys')
Type: Runtime
The `sys` module is deprecated. Please use the [`util`][] module instead.
### DEP0026: util.print()
Type: End-of-Life
`util.print()` has been removed. Please use [`console.log()`][] instead.
### DEP0027: util.puts()
Type: End-of-Life
`util.puts()` has been removed. Please use [`console.log()`][] instead.
### DEP0028: util.debug()
Type: End-of-Life
`util.debug()` has been removed. Please use [`console.error()`][] instead.
### DEP0029: util.error()
Type: End-of-Life
`util.error()` has been removed. Please use [`console.error()`][] instead.
### DEP0030: SlowBuffer
Type: Documentation-only
The [`SlowBuffer`][] class is 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 is
deprecated. Please use [`emitter.listenerCount(eventName)`][] instead.
### DEP0034: fs.exists(path, callback)
Type: Documentation-only
The [`fs.exists(path, callback)`][] API is 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 is deprecated.
### DEP0036: fs.lchmodSync(path, mode)
Type: Documentation-only
The [`fs.lchmodSync(path, mode)`][] API is deprecated.
### DEP0037: fs.lchown(path, uid, gid, callback)
Type: Deprecation revoked
The [`fs.lchown(path, uid, gid, callback)`][] API was deprecated. The
deprecation was revoked because the requisite supporting APIs were added in
libuv.
### DEP0038: fs.lchownSync(path, uid, gid)
Type: Deprecation revoked
The [`fs.lchownSync(path, uid, gid)`][] API was deprecated. The deprecation was
revoked because the requisite supporting APIs were added in libuv.
### DEP0039: require.extensions
Type: Documentation-only
The [`require.extensions`][] property is deprecated.
### DEP0040: punycode module
Type: Documentation-only
The [`punycode`][] module is deprecated. Please use a userland alternative
instead.
### DEP0041: NODE\_REPL\_HISTORY\_FILE environment variable
Type: End-of-Life
The `NODE_REPL_HISTORY_FILE` environment variable was removed. Please use
`NODE_REPL_HISTORY` instead.
### DEP0042: tls.CryptoStream
Type: End-of-Life
The [`tls.CryptoStream`][] class was removed. Please use
[`tls.TLSSocket`][] instead.
### DEP0043: tls.SecurePair
Type: Documentation-only
The [`tls.SecurePair`][] class is deprecated. Please use
[`tls.TLSSocket`][] instead.
### DEP0044: util.isArray()
Type: Documentation-only
The [`util.isArray()`][] API is deprecated. Please use `Array.isArray()`
instead.
### DEP0045: util.isBoolean()
Type: Documentation-only
The [`util.isBoolean()`][] API is deprecated.
### DEP0046: util.isBuffer()
Type: Documentation-only
The [`util.isBuffer()`][] API is deprecated. Please use
[`Buffer.isBuffer()`][] instead.
### DEP0047: util.isDate()
Type: Documentation-only
The [`util.isDate()`][] API is deprecated.
### DEP0048: util.isError()
Type: Documentation-only
The [`util.isError()`][] API is deprecated.
### DEP0049: util.isFunction()
Type: Documentation-only
The [`util.isFunction()`][] API is deprecated.
### DEP0050: util.isNull()
Type: Documentation-only
The [`util.isNull()`][] API is deprecated.
### DEP0051: util.isNullOrUndefined()
Type: Documentation-only
The [`util.isNullOrUndefined()`][] API is deprecated.
### DEP0052: util.isNumber()
Type: Documentation-only
The [`util.isNumber()`][] API is deprecated.
### DEP0053 util.isObject()
Type: Documentation-only
The [`util.isObject()`][] API is deprecated.
### DEP0054: util.isPrimitive()
Type: Documentation-only
The [`util.isPrimitive()`][] API is deprecated.
### DEP0055: util.isRegExp()
Type: Documentation-only
The [`util.isRegExp()`][] API is deprecated.
### DEP0056: util.isString()
Type: Documentation-only
The [`util.isString()`][] API is deprecated.
### DEP0057: util.isSymbol()
Type: Documentation-only
The [`util.isSymbol()`][] API is deprecated.
### DEP0058: util.isUndefined()
Type: Documentation-only
The [`util.isUndefined()`][] API is deprecated.
### DEP0059: util.log()
Type: Documentation-only
The [`util.log()`][] API is deprecated.
### DEP0060: util.\_extend()
Type: Documentation-only
The [`util._extend()`][] API is deprecated.
### DEP0061: fs.SyncWriteStream
Type: End-of-Life
The `fs.SyncWriteStream` class was never intended to be a publicly accessible
API and has been removed. No alternative API is available. Please use a userland
alternative.
### DEP0062: node --debug
Type: End-of-Life
`--debug` activates the legacy V8 debugger interface, which was 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 is
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: End-of-Life
The `repl` module's `REPL_MODE_MAGIC` constant, used for `replMode` option, has
been removed. Its behavior has been functionally identical to that of
`REPL_MODE_SLOPPY` since Node.js 6.0.0, 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 value, `magic`, is also
removed. Please use `sloppy` instead.
### DEP0066: OutgoingMessage.prototype.\_headers, OutgoingMessage.prototype.\_headerNames
Type: Runtime
The `http` module `OutgoingMessage.prototype._headers` and
`OutgoingMessage.prototype._headerNames` properties are deprecated. Use one of
the public methods (e.g. `OutgoingMessage.prototype.getHeader()`,
`OutgoingMessage.prototype.getHeaders()`,
`OutgoingMessage.prototype.getHeaderNames()`,
`OutgoingMessage.prototype.hasHeader()`,
`OutgoingMessage.prototype.removeHeader()`,
`OutgoingMessage.prototype.setHeader()`) for working with outgoing headers.
The `OutgoingMessage.prototype._headers` and
`OutgoingMessage.prototype._headerNames` properties were never documented as
officially supported properties.
### DEP0067: OutgoingMessage.prototype.\_renderHeaders
Type: Documentation-only
The `http` module `OutgoingMessage.prototype._renderHeaders()` API is
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: End-of-Life
DebugContext has been removed in V8 and is not available in Node.js 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: End-of-Life
Accessing several internal, undocumented properties of `net.Server` instances
with inappropriate names is 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:
```js
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:
```sh
> 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()` is 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: End-of-Life
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 backward 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 is 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 is
deprecated. Please use `fs.ftruncate()` or `fs.ftruncateSync()` to work with
file descriptors.
### DEP0082: REPLServer.prototype.memory()
Type: Runtime
`REPLServer.prototype.memory()` is only necessary for the internal mechanics of
the `REPLServer` itself. Do not use this function.
### DEP0083: Disabling ECDH by setting ecdhCurve to false
Type: End-of-Life.
The `ecdhCurve` option to `tls.createSecureContext()` and `tls.TLSSocket` could
be set to `false` to disable ECDH entirely on the server only. This mode was
deprecated in preparation for migrating to OpenSSL 1.1.0 and consistency with
the client and is now unsupported. Use the `ciphers` parameter instead.
### DEP0084: requiring bundled internal dependencies
Type: End-of-Life
Since Node.js versions 4.4.0 and 5.2.0, several modules only intended for
internal usage were mistakenly exposed to user code through `require()`. These
modules were:
* `v8/tools/codemap`
* `v8/tools/consarray`
* `v8/tools/csvparser`
* `v8/tools/logreader`
* `v8/tools/profile_view`
* `v8/tools/profile`
* `v8/tools/SourceMap`
* `v8/tools/splaytree`
* `v8/tools/tickprocessor-driver`
* `v8/tools/tickprocessor`
* `node-inspect/lib/_inspect` (from 7.6.0)
* `node-inspect/lib/internal/inspect_client` (from 7.6.0)
* `node-inspect/lib/internal/inspect_repl` (from 7.6.0)
The `v8/*` modules do not have any exports, and if not imported in a specific
order would in fact throw errors. As such there are virtually no legitimate use
cases for importing them through `require()`.
On the other hand, `node-inspect` may be installed locally through a package
manager, as it is published on the npm registry under the same name. No source
code modification is necessary if that is done.
### DEP0085: AsyncHooks Sensitive API
Type: End-of-Life
The AsyncHooks Sensitive API was never documented and had various minor issues.
Use the `AsyncResource` API instead. See
.
### DEP0086: Remove runInAsyncIdScope
Type: End-of-Life
`runInAsyncIdScope` doesn't emit the `'before'` or `'after'` event and can thus
cause a lot of issues. See .
### DEP0089: require('assert')
Type: Deprecation revoked
Importing assert directly was not recommended as the exposed functions use
loose equality checks. The deprecation was revoked because use of the `assert`
module is not discouraged, and the deprecation caused end user confusion.
### DEP0090: Invalid GCM authentication tag lengths
Type: End-of-Life
Node.js used to support all GCM authentication tag lengths which are accepted by
OpenSSL when calling [`decipher.setAuthTag()`][]. Beginning with Node.js
v11.0.0, only authentication tag lengths of 128, 120, 112, 104, 96, 64, and 32
bits are allowed. Authentication tags of other lengths are invalid per
[NIST SP 800-38D][].
### DEP0091: crypto.DEFAULT_ENCODING
Type: Runtime
The [`crypto.DEFAULT_ENCODING`][] property is deprecated.
### DEP0092: Top-level `this` bound to `module.exports`
Type: Documentation-only
Assigning properties to the top-level `this` as an alternative
to `module.exports` is deprecated. Developers should use `exports`
or `module.exports` instead.
### DEP0093: crypto.fips is deprecated and replaced.
Type: Documentation-only
The [`crypto.fips`][] property is deprecated. Please use `crypto.setFips()`
and `crypto.getFips()` instead.
### DEP0094: Using `assert.fail()` with more than one argument.
Type: Runtime
Using `assert.fail()` with more than one argument is deprecated. Use
`assert.fail()` with only one argument or use a different `assert` module
method.
### DEP0095: timers.enroll()
Type: Runtime
`timers.enroll()` is deprecated. Please use the publicly documented
[`setTimeout()`][] or [`setInterval()`][] instead.
### DEP0096: timers.unenroll()
Type: Runtime
`timers.unenroll()` is deprecated. Please use the publicly documented
[`clearTimeout()`][] or [`clearInterval()`][] instead.
### DEP0097: MakeCallback with domain property
Type: Runtime
Users of `MakeCallback` that add the `domain` property to carry context,
should start using the `async_context` variant of `MakeCallback` or
`CallbackScope`, or the high-level `AsyncResource` class.
### DEP0098: AsyncHooks Embedder AsyncResource.emitBefore and AsyncResource.emitAfter APIs
Type: End-of-Life
The embedded API provided by AsyncHooks exposes `.emitBefore()` and
`.emitAfter()` 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
.
### DEP0099: async context-unaware node::MakeCallback C++ APIs
Type: Compile-time
Certain versions of `node::MakeCallback` APIs available to native modules are
deprecated. Please use the versions of the API that accept an `async_context`
parameter.
### DEP0100: process.assert()
Type: Runtime
`process.assert()` is deprecated. Please use the [`assert`][] module instead.
This was never a documented feature.
### DEP0101: --with-lttng
Type: End-of-Life
The `--with-lttng` compile-time option has been removed.
### DEP0102: Using `noAssert` in Buffer#(read|write) operations.
Type: End-of-Life
Using the `noAssert` argument has no functionality anymore. All input is going
to be verified, no matter if it is set to true or not. Skipping the verification
could lead to hard to find errors and crashes.
### DEP0103: process.binding('util').is\[...\] typechecks
Type: Documentation-only (supports [`--pending-deprecation`][])
Using `process.binding()` in general should be avoided. The type checking
methods in particular can be replaced by using [`util.types`][].
This deprecation has been superseded by the deprecation of the
`process.binding()` API ([DEP0111](#DEP0111)).
### DEP0104: process.env string coercion
Type: Documentation-only (supports [`--pending-deprecation`][])
When assigning a non-string property to [`process.env`][], the assigned value is
implicitly converted to a string. This behavior is deprecated if the assigned
value is not a string, boolean, or number. In the future, such assignment may
result in a thrown error. Please convert the property to a string before
assigning it to `process.env`.
### DEP0105: decipher.finaltol
Type: End-of-Life
`decipher.finaltol()` has never been documented and was an alias for
[`decipher.final()`][]. This API has been removed, and it is recommended to use
[`decipher.final()`][] instead.
### DEP0106: crypto.createCipher and crypto.createDecipher
Type: Runtime
Using [`crypto.createCipher()`][] and [`crypto.createDecipher()`][] should be
avoided as they use a weak key derivation function (MD5 with no salt) and static
initialization vectors. It is recommended to derive a key using
[`crypto.pbkdf2()`][] or [`crypto.scrypt()`][] and to use
[`crypto.createCipheriv()`][] and [`crypto.createDecipheriv()`][] to obtain the
[`Cipher`][] and [`Decipher`][] objects respectively.
### DEP0107: tls.convertNPNProtocols()
Type: End-of-Life
This was an undocumented helper function not intended for use outside Node.js
core and obsoleted by the removal of NPN (Next Protocol Negotiation) support.
### DEP0108: zlib.bytesRead
Type: Runtime
Deprecated alias for [`zlib.bytesWritten`][]. This original name was chosen
because it also made sense to interpret the value as the number of bytes
read by the engine, but is inconsistent with other streams in Node.js that
expose values under these names.
### DEP0109: http, https, and tls support for invalid URLs
Type: Runtime
Some previously supported (but strictly invalid) URLs were accepted through the
[`http.request()`][], [`http.get()`][], [`https.request()`][],
[`https.get()`][], and [`tls.checkServerIdentity()`][] APIs because those were
accepted by the legacy `url.parse()` API. The mentioned APIs now use the WHATWG
URL parser that requires strictly valid URLs. Passing an invalid URL is
deprecated and support will be removed in the future.
### DEP0110: vm.Script cached data
Type: Documentation-only
The `produceCachedData` option is deprecated. Use
[`script.createCachedData()`][] instead.
### DEP0111: process.binding()
Type: Documentation-only (supports [`--pending-deprecation`][])
`process.binding()` is for use by Node.js internal code only.
### DEP0112: dgram private APIs
Type: Runtime
The `dgram` module previously contained several APIs that were never meant to
accessed outside of Node.js core: `Socket.prototype._handle`,
`Socket.prototype._receiving`, `Socket.prototype._bindState`,
`Socket.prototype._queue`, `Socket.prototype._reuseAddr`,
`Socket.prototype._healthCheck()`, `Socket.prototype._stopReceiving()`, and
`dgram._createSocketHandle()`.
### DEP0113: Cipher.setAuthTag(), Decipher.getAuthTag()
Type: End-of-Life
`Cipher.setAuthTag()` and `Decipher.getAuthTag()` are no longer available. They
were never documented and would throw when called.
### DEP0114: crypto._toBuf()
Type: End-of-Life
The `crypto._toBuf()` function was not designed to be used by modules outside
of Node.js core and was removed.
### DEP0115: crypto.prng(), crypto.pseudoRandomBytes(), crypto.rng()
Type: Documentation-only (supports [`--pending-deprecation`][])
In recent versions of Node.js, there is no difference between
[`crypto.randomBytes()`][] and `crypto.pseudoRandomBytes()`. The latter is
deprecated along with the undocumented aliases `crypto.prng()` and
`crypto.rng()` in favor of [`crypto.randomBytes()`][] and may be removed in a
future release.
### DEP0116: Legacy URL API
Type: Documentation-only
The [Legacy URL API][] is deprecated. This includes [`url.format()`][],
[`url.parse()`][], [`url.resolve()`][], and the [legacy `urlObject`][]. Please
use the [WHATWG URL API][] instead.
### DEP0117: Native crypto handles
Type: End-of-Life
Previous versions of Node.js exposed handles to internal native objects through
the `_handle` property of the `Cipher`, `Decipher`, `DiffieHellman`,
`DiffieHellmanGroup`, `ECDH`, `Hash`, `Hmac`, `Sign`, and `Verify` classes.
The `_handle` property has been removed because improper use of the native
object can lead to crashing the application.
### DEP0118: dns.lookup() support for a falsy hostname
Type: Runtime
Previous versions of Node.js supported `dns.lookup()` with a falsy hostname
like `dns.lookup(false)` due to backward compatibility.
This behavior is undocumented and is thought to be unused in real world apps.
It will become an error in future versions of Node.js.
### DEP0119: process.binding('uv').errname() private API
Type: Documentation-only (supports [`--pending-deprecation`][])
`process.binding('uv').errname()` is deprecated. Please use
[`util.getSystemErrorName()`][] instead.
### DEP0120: Windows Performance Counter Support
Type: End-of-Life
Windows Performance Counter support has been removed from Node.js. The
undocumented `COUNTER_NET_SERVER_CONNECTION()`,
`COUNTER_NET_SERVER_CONNECTION_CLOSE()`, `COUNTER_HTTP_SERVER_REQUEST()`,
`COUNTER_HTTP_SERVER_RESPONSE()`, `COUNTER_HTTP_CLIENT_REQUEST()`, and
`COUNTER_HTTP_CLIENT_RESPONSE()` functions have been deprecated.
### DEP0121: net._setSimultaneousAccepts()
Type: Runtime
The undocumented `net._setSimultaneousAccepts()` function was originally
intended for debugging and performance tuning when using the `child_process`
and `cluster` modules on Windows. The function is not generally useful and
is being removed. See discussion here:
https://github.com/nodejs/node/issues/18391
### DEP0122: tls Server.prototype.setOptions()
Type: Runtime
Please use `Server.prototype.setSecureContext()` instead.
### DEP0123: setting the TLS ServerName to an IP address
Type: Runtime
Setting the TLS ServerName to an IP address is not permitted by
[RFC 6066][]. This will be ignored in a future version.
### DEP0124: using REPLServer.rli
Type: Runtime
This property is a reference to the instance itself.
### DEP0125: require('\_stream\_wrap')
Type: Runtime
The `_stream_wrap` module is deprecated.
### DEP0126: timers.active()
Type: Runtime
The previously undocumented `timers.active()` is deprecated.
Please use the publicly documented [`timeout.refresh()`][] instead.
If re-referencing the timeout is necessary, [`timeout.ref()`][] can be used
with no performance impact since Node.js 10.
### DEP0127: timers._unrefActive()
Type: Runtime
The previously undocumented and "private" `timers._unrefActive()` is deprecated.
Please use the publicly documented [`timeout.refresh()`][] instead.
If unreferencing the timeout is necessary, [`timeout.unref()`][] can be used
with no performance impact since Node.js 10.
### DEP0128: modules with an invalid `main` entry and an `index.js` file
Type: Documentation-only (supports [`--pending-deprecation`][])
Modules that have an invalid `main` entry (e.g., `./does-not-exist.js`) and
also have an `index.js` file in the top level directory will resolve the
`index.js` file. That is deprecated and is going to throw an error in future
Node.js versions.
### DEP0129: ChildProcess._channel
Type: Documentation-only
The `_channel` property of child process objects returned by `spawn()` and
similar functions is not intended for public use. Use `ChildProcess.channel`
instead.
### DEP0130: Module.createRequireFromPath()
Type: Documentation-only
Module.createRequireFromPath() is deprecated. Please use [`module.createRequire()`][] instead.
### DEP0131: Legacy HTTP parser
Type: Documentation-only
The legacy HTTP parser, used by default in versions of Node.js prior to 12.0.0,
is deprecated. This deprecation applies to users of the
[`--http-parser=legacy`][] command-line flag.
### DEP0132: worker.terminate() with callback
Type: Runtime
Passing a callback to [`worker.terminate()`][] is deprecated. Use the returned
`Promise` instead, or a listener to the worker’s `'exit'` event.
### DEP0133: http connection
Type: Documentation-only
Prefer [`response.socket`][] over [`response.connection`][] and
[`request.socket`][] over [`request.connection`][].
### DEP0134: process._tickCallback
Type: Documentation-only (supports [`--pending-deprecation`][])
The `process._tickCallback` property was never documented as
an officially supported API.
[`--http-parser=legacy`]: cli.html#cli_http_parser_library
[`--pending-deprecation`]: cli.html#cli_pending_deprecation
[`--throw-deprecation`]: cli.html#cli_throw_deprecation
[`Buffer.allocUnsafeSlow(size)`]: buffer.html#buffer_class_method_buffer_allocunsafeslow_size
[`Buffer.from(array)`]: buffer.html#buffer_class_method_buffer_from_array
[`Buffer.from(buffer)`]: buffer.html#buffer_class_method_buffer_from_buffer
[`Buffer.isBuffer()`]: buffer.html#buffer_class_method_buffer_isbuffer_obj
[`Cipher`]: crypto.html#crypto_class_cipher
[`Decipher`]: crypto.html#crypto_class_decipher
[`EventEmitter.listenerCount(emitter, eventName)`]: events.html#events_eventemitter_listenercount_emitter_eventname
[`REPLServer.clearBufferedCommand()`]: repl.html#repl_replserver_clearbufferedcommand
[`Server.connections`]: net.html#net_server_connections
[`Server.getConnections()`]: net.html#net_server_getconnections_callback
[`Server.listen({fd: })`]: net.html#net_server_listen_handle_backlog_callback
[`SlowBuffer`]: buffer.html#buffer_class_slowbuffer
[`assert`]: assert.html
[`asyncResource.runInAsyncScope()`]: async_hooks.html#async_hooks_asyncresource_runinasyncscope_fn_thisarg_args
[`child_process`]: child_process.html
[`clearInterval()`]: timers.html#timers_clearinterval_timeout
[`clearTimeout()`]: timers.html#timers_cleartimeout_timeout
[`console.error()`]: console.html#console_console_error_data_args
[`console.log()`]: console.html#console_console_log_data_args
[`crypto.DEFAULT_ENCODING`]: crypto.html#crypto_crypto_default_encoding
[`crypto.createCipher()`]: crypto.html#crypto_crypto_createcipher_algorithm_password_options
[`crypto.createCipheriv()`]: crypto.html#crypto_crypto_createcipheriv_algorithm_key_iv_options
[`crypto.createDecipher()`]: crypto.html#crypto_crypto_createdecipher_algorithm_password_options
[`crypto.createDecipheriv()`]: crypto.html#crypto_crypto_createdecipheriv_algorithm_key_iv_options
[`crypto.fips`]: crypto.html#crypto_crypto_fips
[`crypto.pbkdf2()`]: crypto.html#crypto_crypto_pbkdf2_password_salt_iterations_keylen_digest_callback
[`crypto.randomBytes()`]: crypto.html#crypto_crypto_randombytes_size_callback
[`crypto.scrypt()`]: crypto.html#crypto_crypto_scrypt_password_salt_keylen_options_callback
[`decipher.final()`]: crypto.html#crypto_decipher_final_outputencoding
[`decipher.setAuthTag()`]: crypto.html#crypto_decipher_setauthtag_buffer
[`domain`]: domain.html
[`ecdh.setPublicKey()`]: crypto.html#crypto_ecdh_setpublickey_publickey_encoding
[`emitter.listenerCount(eventName)`]: events.html#events_emitter_listenercount_eventname
[`fs.access()`]: fs.html#fs_fs_access_path_mode_callback
[`fs.exists(path, callback)`]: fs.html#fs_fs_exists_path_callback
[`fs.lchmod(path, mode, callback)`]: fs.html#fs_fs_lchmod_path_mode_callback
[`fs.lchmodSync(path, mode)`]: fs.html#fs_fs_lchmodsync_path_mode
[`fs.lchown(path, uid, gid, callback)`]: fs.html#fs_fs_lchown_path_uid_gid_callback
[`fs.lchownSync(path, uid, gid)`]: fs.html#fs_fs_lchownsync_path_uid_gid
[`fs.read()`]: fs.html#fs_fs_read_fd_buffer_offset_length_position_callback
[`fs.readSync()`]: fs.html#fs_fs_readsync_fd_buffer_offset_length_position
[`fs.stat()`]: fs.html#fs_fs_stat_path_options_callback
[`http.get()`]: http.html#http_http_get_options_callback
[`http.request()`]: http.html#http_http_request_options_callback
[`https.get()`]: https.html#https_https_get_options_callback
[`https.request()`]: https.html#https_https_request_options_callback
[`module.createRequire()`]: modules.html#modules_module_createrequire_filename
[`os.networkInterfaces()`]: os.html#os_os_networkinterfaces
[`os.tmpdir()`]: os.html#os_os_tmpdir
[`process.env`]: process.html#process_process_env
[`punycode`]: punycode.html
[`require.extensions`]: modules.html#modules_require_extensions
[`script.createCachedData()`]: vm.html#vm_script_createcacheddata
[`setInterval()`]: timers.html#timers_setinterval_callback_delay_args
[`setTimeout()`]: timers.html#timers_settimeout_callback_delay_args
[`timeout.ref()`]: timers.html#timers_timeout_ref
[`timeout.refresh()`]: timers.html#timers_timeout_refresh
[`timeout.unref()`]: timers.html#timers_timeout_unref
[`tls.CryptoStream`]: tls.html#tls_class_cryptostream
[`tls.SecureContext`]: tls.html#tls_tls_createsecurecontext_options
[`tls.SecurePair`]: tls.html#tls_class_securepair
[`tls.TLSSocket`]: tls.html#tls_class_tls_tlssocket
[`tls.checkServerIdentity()`]: tls.html#tls_tls_checkserveridentity_hostname_cert
[`tls.createSecureContext()`]: tls.html#tls_tls_createsecurecontext_options
[`url.format()`]: url.html#url_url_format_urlobject
[`url.parse()`]: url.html#url_url_parse_urlstring_parsequerystring_slashesdenotehost
[`url.resolve()`]: url.html#url_url_resolve_from_to
[`util._extend()`]: util.html#util_util_extend_target_source
[`util.getSystemErrorName()`]: util.html#util_util_getsystemerrorname_err
[`util.inspect()`]: util.html#util_util_inspect_object_options
[`util.inspect.custom`]: util.html#util_util_inspect_custom
[`util.isArray()`]: util.html#util_util_isarray_object
[`util.isBoolean()`]: util.html#util_util_isboolean_object
[`util.isBuffer()`]: util.html#util_util_isbuffer_object
[`util.isDate()`]: util.html#util_util_isdate_object
[`util.isError()`]: util.html#util_util_iserror_object
[`util.isFunction()`]: util.html#util_util_isfunction_object
[`util.isNull()`]: util.html#util_util_isnull_object
[`util.isNullOrUndefined()`]: util.html#util_util_isnullorundefined_object
[`util.isNumber()`]: util.html#util_util_isnumber_object
[`util.isObject()`]: util.html#util_util_isobject_object
[`util.isPrimitive()`]: util.html#util_util_isprimitive_object
[`util.isRegExp()`]: util.html#util_util_isregexp_object
[`util.isString()`]: util.html#util_util_isstring_object
[`util.isSymbol()`]: util.html#util_util_issymbol_object
[`util.isUndefined()`]: util.html#util_util_isundefined_object
[`util.log()`]: util.html#util_util_log_string
[`util.types`]: util.html#util_util_types
[`util`]: util.html
[`worker.exitedAfterDisconnect`]: cluster.html#cluster_worker_exitedafterdisconnect
[`worker.terminate()`]: worker_threads.html#worker_threads_worker_terminate
[`zlib.bytesWritten`]: zlib.html#zlib_zlib_byteswritten
[Legacy URL API]: url.html#url_legacy_url_api
[NIST SP 800-38D]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf
[RFC 6066]: https://tools.ietf.org/html/rfc6066#section-3
[WHATWG URL API]: url.html#url_the_whatwg_url_api
[alloc]: buffer.html#buffer_class_method_buffer_alloc_size_fill_encoding
[alloc_unsafe_size]: buffer.html#buffer_class_method_buffer_allocunsafe_size
[from_arraybuffer]: buffer.html#buffer_class_method_buffer_from_arraybuffer_byteoffset_length
[from_string_encoding]: buffer.html#buffer_class_method_buffer_from_string_encoding
[legacy `urlObject`]: url.html#url_legacy_urlobject