The Node.js Runtime Renaissance

ConFoo 2023
Node.js
Runtime
ruyadorno.com
The
Renaissance

View Slide

Ruy Adorno
 
Based in Montreal

Node.js Collaborator & Releaser.
 
Working with Node.js things at Google

@[email protected]
The Node.js Runtime Renaissance
ConFoo 2023 ruyadorno.com

View Slide

Chronology
2022 features
What’s next in 2023
ToC
The Node.js Runtime
Renaissance

View Slide

Chronology

View Slide

2009
Ryan Dahl writes the initial
implementation of the Node.js
runtime

View Slide

2010
npm initial release

View Slide

2011
npm bundled with Node.js

View Slide

2014
io.js fork

View Slide

2015
Node.js Foundation announced,
Node.js and io.js merged back
together

View Slide

2015
Welcome to the
Renaissance era!

View Slide

2017
Ruy Adorno
fi
rst
commit to the project

View Slide

2018
Ryan Dahl announces the work on
Deno, a new JavaScript runtime

View Slide

2019
Node.js Foundation and the JS
Foundation merge together forming
the OpenJS Foundation

View Slide

2020
Deno v1.0 is released

View Slide

The end of the
small core
Most collaborators these days are open to
the idea of adding more features in order to
provide a batteries-included experience in
order to improve DX.

View Slide

2022
Welcome to the
Industrial era!

View Slide

The Node.js Runtime Renaissance Industrialization
2022
Welcome to the
Industrial era!

View Slide

5 exciting recent
features

View Slide

Test Runner
The Node.js Runtime
Renaissance

View Slide

Test Runner
Shipped initially in v18.0.0, the test runner
was initially designed to be a minimal viable
test runner but has been getting more and
more features since then.

View Slide

Test Runner
- Mocks added in v18.13.0, v19.1.0
 
- Reporters added in v19.6.0
 
- Coverage added in v19.7.0 (this week!)

View Slide

import assert from 'node:assert';
import test from 'node:test';
import {splitChars} from './split-chars.mjs';
test('test splitChars function', async t => {
const input = 'a:b:c';
const expected = ['a', 'b', 'c'];
assert.deepStrictEqual(
splitChars(input),
expected,
'should return expected characters'
);
})
test-runner.mjs

View Slide

$ node test-runner.mjs
TAP version 13
# Subtest: test splitChars function
ok 1 - test splitChars function
---
duration_ms: 4.859125
...
1..1
# tests 1
# pass 1
# fail 0
# cancelled 0
# skipped 0
# todo 0
# duration_ms 59.869375
shell

View Slide

$ node --test
TAP version 13
---
...
1..1
# tests 1
# pass 1
# fail 0
# cancelled 0
# skipped 0
# todo 0
shell

View Slide

How the test runner
finds what files to run
- skip node_modules folders
 
- if a test folder is found, recursively
fi
nd
all .js .cjs .mjs
fi
les
 
- in other folders, match:
 
- Files named test: ^test$
 
- Filenames that start with test-: ^test-.+
 
- Filenames that ends with -test: .+[\.\-\_]test$

View Slide

Learn more
https://nodejs.org/dist/latest-v18.x/docs/api/test.html

View Slide

File Watcher
The Node.js Runtime
Renaissance

View Slide

File Watcher
First introduced in v18.11.0 and v16.19.0, the
fi
le watcher is a native way to have the node
runtime reload anytime watched
fi
les are
modi
fi
ed.

View Slide

import assert from 'node:assert';
import test from 'node:test';
import {splitChars} from './split-chars.mjs';
test('test splitChars function', async t => {
const input = 'a:b:c';
const expected = ['a', 'b', 'c'];
assert.deepStrictEqual(
splitChars(input),
expected,
'should return expected characters'
);
})
test-runner.mjs shell
$ node --watch test-runner.mjs
(node:42453) ExperimentalWarning: Watch mode is  
an experimental feature and might change at any  
time
(Use `node --trace-warnings ...` to show where  
the warning was created)
TAP version 13
---
...
1..1
# tests 1
# pass 1
# fail 0
# cancelled 0
# skipped 0
# todo 0
# duration_ms 6.377
Completed running 'test-runner.mjs'

View Slide

export function splitChars(str) {
return str.split(':');
}
split-chars.mjs shell
$ node --watch test-runner.mjs
(node:42453) ExperimentalWarning: Watch mode is  
an experimental feature and might change at any  
time
(Use `node --trace-warnings ...` to show where  
the warning was created)
TAP version 13
---
...
1..1
# tests 1
# pass 1
# fail 0
# cancelled 0
# skipped 0
# todo 0
# duration_ms 6.377

View Slide

return str.split('d');
}
Restarting 'test-runner.mjs'
TAP version 13
not ok 1 - test splitChars function
---
failureType: 'testCodeFailure'
error: 'should return expected characters'
code: 'ERR_ASSERTION'
0: 'a'
1: 'b'
2: 'c'
0: 'a:b:c'
operator: 'deepStrictEqual'
...
1..1
# tests 1
# pass 0
# fail 1
Failed running 'test-runner.mjs'

View Slide

return str.split(':');
}
Restarting 'test-runner.mjs'
TAP version 13
---
...
1..1
# tests 1
# pass 1
# fail 0
# cancelled 0
# skipped 0
# todo 0

View Slide

More options
- --watch-path specify what exact folders /
fi
les
to watch, disable watching of imported modules
 
- --watch-preserve-output disable clearing the
console when watch mode restarts the process

View Slide

Learn more
https://nodejs.org/dist/latest-v18.x/docs/api/cli.html#--watch

View Slide

Argument
Parser
The Node.js Runtime
Renaissance

View Slide

Argument Parser
Initially added in v18.3.0 and v16.17.0, the
argument parser is an opinionated way to
handle command line arguments in your
apps without the need of an extra package.

View Slide

Argument Parser
Made in collaboration between the
maintainers of yargs and Commander ,
two of the most popular argument parsers.

View Slide

Argument Parser
Currently an experimental API but should be
promoted to stable soon. Unlikely to have
changes at this point.

View Slide

import { parseArgs } from 'node:util';
const { values } =
parseArgs({
options: {
active: { type: 'boolean' },
pathname: { type: 'string' },
},
});
if (Object.keys(values).length) {
console.table(values)
}
cli-parse-args.mjs

View Slide

$ node cli-parse-args.mjs --active \
--pathname=./cli-parse-args.mjs
┌──────────┬────────────────────────┐
│ (index) │ Values │
├──────────┼────────────────────────┤
│ active │ true │
│ pathname │ './cli-parse-args.mjs' │
└──────────┴────────────────────────┘
shell

View Slide

Highly customizable
The argument parser has much more options such
as support to positional values, loose mode,
providing default values, etc.

View Slide

Learn more
https://nodejs.org/dist/latest-v18.x/docs/api/util.html#utilparseargscon
fi
g

View Slide

Fetch
The Node.js Runtime
Renaissance

View Slide

Fetch
After many years in the making, the fetch()
method is
fi
nally available in Node.js starting
at version v18.3.0 and up.

View Slide

const res = await fetch('https://nodejs.org/dist/index.json', {
method: 'GET',
headers: [
['Accept', 'application/json'],
],
})
const data = await res.json()
const versions = data
.map(i => ({ version: i.version, date: i.date }))
.slice(0, 10)
console.table(versions)
fetch-something.mjs

View Slide

$ node fetch-something.mjs
┌─────────┬───────────┬──────────────┐
│ (index) │ version │ date │
├─────────┼───────────┼──────────────┤
│ 0 │ 'v19.7.0' │ '2023-02-21' │
│ 1 │ 'v19.6.1' │ '2023-02-16' │
│ 2 │ 'v19.6.0' │ '2023-02-01' │
│ 3 │ 'v19.5.0' │ '2023-01-24' │
│ 4 │ 'v19.4.0' │ '2023-01-05' │
│ 5 │ 'v19.3.0' │ '2022-12-14' │
│ 6 │ 'v19.2.0' │ '2022-11-29' │
│ 7 │ 'v19.1.0' │ '2022-11-14' │
│ 8 │ 'v19.0.1' │ '2022-11-04' │
│ 9 │ 'v19.0.0' │ '2022-10-17' │
└─────────┴───────────┴──────────────┘
shell

View Slide

Stream iterator
methods and Stream
Web API helpers
The Node.js Runtime
Renaissance

View Slide

Stream iterator methods
A variety of stream iterator methods have
been introduced between v17.4.0 and
v17.5.0. Some of these methods may also be
available in v16.4.0.

View Slide

import { Readable } from 'node:stream';
const s = Readable.from([1, 2, 3, 4]);
const mapped = []
s.on('data', data => {
mapped.push(data * 2);
})
s.on('end', () => {
for (const m of mapped) {
console.log(m)
}
})
map-stream-before.mjs map-stream-iterator.mjs
const s = Readable.from([1, 2, 3, 4]);
const mapped = s.map(i => i * 2);
for await (const m of mapped) {
console.log(m);
}

View Slide

Web Stream API
Utility Consumers
Added in v16.7.0, providing helper methods
to help collect stream data.

View Slide

Web Stream API
Utility Consumers
There are also utility consumers for
arrayBuffer , blob , buffer and json .

View Slide

Learn more
https://nodejs.org/dist/latest-v18.x/docs/api/stream.html#readablemapfn-options
 
https://nodejs.org/dist/latest-v18.x/docs/api/webstreams.html#utility-consumers

View Slide

2023
Coming up

this year

View Slide

Single Executable  
Apps
The Node.js Runtime
Renaissance

View Slide

Single Executable Apps
(Just landed!) Added in v19.7.0, there’s now
a way to package your app code along with
the Node.js runtime so that you can
distribute a single executable binary
fi
le.

View Slide

Learn more
https://nodejs.org/docs/latest-v19.x/api/single-executable-applications.html

View Slide

Process-based
Permissions
The Node.js Runtime
Renaissance

View Slide

Process-based
Permissions
(Work in progress) New options to restrict
access to speci
fi
c resources (such as
fi
le
system, child process, workers) during
execution.

View Slide

Process-based
Permissions
Very likely to still change, this new
permission model is going to be behind a
fl
ag: --experimental-permission

View Slide

$ node --experimental-permission index.js
node:internal/modules/cjs/loader:171
const result = internalModuleStat(filename);
^
Error: Access to this API has been restricted
code: 'ERR_ACCESS_DENIED',
permission: ‘FileSystemRead'
$ node --experimental-permission --allow-fs-read=* --allow-fs-write=./tmp index.js
Hello world!
(node:19836) ExperimentalWarning: Permission is an experimental feature
(Use `node --trace-warnings ...` to show where the warning was created)
shell

View Slide

Learn more
https://github.com/nodejs/node/pull/44004

View Slide

Want to learn even more?
Join one of the Working Groups meetings: https://nodejs.org/calendar
 
Join the OpenJS Foundation Slack: https://slack-invite.openjsf.org

Repository: https://github.com/nodejs/node
 
Website: https://nodejs.org

View Slide

Merci!
@[email protected]

View Slide

The Node.js Runtime Renaissance

The Node.js Runtime Renaissance

Ruy Adorno

More Decks by Ruy Adorno

Other Decks in Programming

Featured

Transcript