Notable Changes:
Diagnostics channel (experimental module):
`diagnostics_channel` is a new experimental module that provides an API
to create named channels to report arbitrary message data for
diagnostics purposes.
The module was initially introduced in Node.js v15.1.0 and is
backported to v14.17.0 to enable testing it at a larger scale.
With `diagnostics_channel`, Node.js core and module authors can publish
contextual data about what they are doing at a given time. This could
be the hostname and query string of a mysql query, for example. Just
create a named channel with `dc.channel(name)` and call
`channel.publish(data)` to send the data to any listeners to that
channel.
```js
const dc = require('diagnostics_channel');
const channel = dc.channel('mysql.query');
MySQL.prototype.query = function query(queryString, values, callback) {
// Broadcast query information whenever a query is made
channel.publish({
query: queryString,
host: this.hostname,
});
this.doQuery(queryString, values, callback);
};
```
Channels are like one big global event emitter but are split into
separate objects to ensure they get the best performance. If nothing is
listening to the channel, the publishing overhead should be as close to
zero as possible. Consuming channel data is as easy as using
`channel.subscribe(listener)` to run a function whenever a message is
published to that channel.
```js
const dc = require('diagnostics_channel');
const channel = dc.channel('mysql.query');
channel.subscribe(({ query, host }) => {
console.log(`mysql query to ${host}: ${query}`);
});
```
The data captured can be used to provide context for what an app is
doing at a given time. This can be used for things like augmenting
tracing data, tracking network and filesystem activity, logging
queries, and many other things. It's also a very useful data source
for diagnostics tools to provide a clearer picture of exactly what the
application is doing at a given point in the data they are presenting.
Contributed by Stephen Belanger (https://github.com/nodejs/node/pull/34895).
UUID support in the crypto module:
The new `crypto.randomUUID()` method now allows to generate random
[RFC 4122](https://www.rfc-editor.org/rfc/rfc4122.txt) Version 4
UUID strings:
```js
const { randomUUID } = require('crypto');
console.log(randomUUID());
// 'aa7c91a1-f8fc-4339-b9db-f93fc7233429'
```
Contributed by James M Snell (https://github.com/nodejs/node/pull/36729).
Experimental support for `AbortController` and `AbortSignal`:
Node.js 14.17.0 adds experimental partial support for `AbortController`
and `AbortSignal`.
Both constructors can be enabled globally using the
`--experimental-abortcontroller` flag.
Additionally, several Node.js APIs have been updated to support
`AbortSignal` for cancellation.
It is not mandatory to use the built-in constructors with them. Any
spec-compliant third-party alternatives should be compatible.
`AbortSignal` support was added to the following methods:
* `child_process.exec`
* `child_process.execFile`
* `child_process.fork`
* `child_process.spawn`
* `dgram.createSocket`
* `events.on`
* `events.once`
* `fs.readFile`
* `fs.watch`
* `fs.writeFile`
* `http.request`
* `https.request`
* `http2Session.request`
* The promisified variants of `setImmediate` and `setTimeout`
Other notable changes:
* doc:
* revoke deprecation of legacy url, change status to legacy (James M Snell) (https://github.com/nodejs/node/pull/37784)
* add legacy status to stability index (James M Snell) (https://github.com/nodejs/node/pull/37784)
* upgrade stability status of report API (Gireesh Punathil) (https://github.com/nodejs/node/pull/35654)
* deps:
* V8: Backport various patches for Apple Silicon support (BoHong Li) (https://github.com/nodejs/node/pull/38051)
* update ICU to 68.1 (Michaël Zasso) (https://github.com/nodejs/node/pull/36187)
* upgrade to libuv 1.41.0 (Colin Ihrig) (https://github.com/nodejs/node/pull/37360)
* http:
* add http.ClientRequest.getRawHeaderNames() (simov) (https://github.com/nodejs/node/pull/37660)
* report request start and end with diagnostics\_channel (Stephen Belanger) (https://github.com/nodejs/node/pull/34895)
* util:
* add getSystemErrorMap() impl (eladkeyshawn) (https://github.com/nodejs/node/pull/38101)
PR-URL: https://github.com/nodejs/node/pull/38507
Notable changes
The legacy HTTP parser is runtime deprecated:
- The legacy HTTP parser, selected by the `--http-parser=legacy` command line
option, is deprecated with the pending End-of-Life of Node.js 10.x (where it
is the only HTTP parser implementation provided) at the end of April 2021. It
will now warn on use but otherwise continue to function and may be removed in
a future Node.js 12.x release.
- The default HTTP parser based on llhttp is not affected. By default it is
stricter than the now deprecated legacy HTTP parser. If interoperability with
HTTP implementations that send invalid HTTP headers is required, the HTTP
parser can be started in a less secure mode with the `--insecure-http-parser`
command line option.
ES Modules:
- ES Modules are now considered stable.
node-api:
- Updated to node-api version 8 and added an experimental API to allow
retrieval of the add-on file name.
New API's to control code coverage data collection:
- `v8.stopCoverage()` and `v8.takeCoverage()` have been added.
New API to monitor event loop utilization by Worker threads
- `worker.performance.eventLoopUtilization()` has been added.
PR-URL: https://github.com/nodejs/node/pull/37797
Fixes: https://github.com/nodejs/node/issues/36098
Co-authored-by: Antoine du Hamel <duhamelantoine1995@gmail.com>
Co-authored-by: Guy Bedford <guybedford@gmail.com>
Co-authored-by: Darshan Sen <raisinten@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/37246
Reviewed-By: Bradley Farias <bradley.meck@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/37400
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Pooja D P <Pooja.D.P@ibm.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>
Reviewed-By: Zijian Liu <lxxyxzj@gmail.com>
I presume "The can..." should be "They can...".
PR-URL: https://github.com/nodejs/node/pull/37417
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Zijian Liu <lxxyxzj@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Pooja D P <Pooja.D.P@ibm.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/36800
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Beth Griggs <bgriggs@redhat.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Pooja D P <Pooja.D.P@ibm.com>
Documents which versions of Node.js support which ESM-feature.
PR-URL: https://github.com/nodejs/node/pull/35395
Reviewed-By: Geoffrey Booth <webmaster@geoffreybooth.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
This provides a number of minor style adjustments and small corrections
to esm.md text.
Co-authored-by: Guy Bedford <guybedford@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/35414
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Derek Lewis <DerekNonGeneric@inf.is>
Reviewed-By: Geoffrey Booth <webmaster@geoffreybooth.com>
This helps catch broken links as part of the test suite. This also
improves the user experience when browsing the markdown files.
PR-URL: https://github.com/nodejs/node/pull/35191
Fixes: https://github.com/nodejs/node/issues/35189
Reviewed-By: Derek Lewis <DerekNonGeneric@inf.is>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
This part of the docs aims to contain documentation regarding package
configuration that covers both ESM and CJS realms.
* Move Enabling section
* Update Enabling section
* Remove -u flag
* Package scopes do not carry through `node_modules` folders
Refs: https://github.com/nodejs/modules/issues/539
Co-authored-by: Geoffrey Booth <webmaster@geoffreybooth.com>>
Co-authored-by: Guy Bedford <guybedford@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/34748
Reviewed-By: Derek Lewis <DerekNonGeneric@inf.is>
Reviewed-By: Geoffrey Booth <webmaster@geoffreybooth.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Ruy Adorno <ruyadorno@github.com>
Using a "Modules:" prefix groups all the related pages together when
using alphabetical order.
Refs: https://github.com/nodejs/modules/issues/539
PR-URL: https://github.com/nodejs/node/pull/34663
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Geoffrey Booth <webmaster@geoffreybooth.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
This patch converts the "read package scope" algorithm's while loop
into a do-while loop enabling items at the filesystem root dir to
be considered within the scope of a sibling package.json also at the
filesystem root dir.
Fixes: https://github.com/nodejs/node/issues/33438
Co-authored-by: Guy Bedford <guybedford@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/34595
Reviewed-By: Jan Krems <jan.krems@gmail.com>
Reviewed-By: Mary Marchini <oss@mmarchini.me>
