📚 PR:

• Fix issue with util.queueMicrotask and cjs loader (#762)
• Working with esm on all versions (#768)

📚 PR:

• Fix Node v16 support and update tap (#754)

This release contains multiple breaking changes. These should not affect the majority of users but it is recommended to consider the full change list.

Improvements

• Improved global API ergonomics (#740)
• Removed --insecure-http-parser support (3d1027f5272f1ffd62a0a990b504636b1a3e158d)
• Pass headers as Buffer (#696)
• Simplify api (#695)
• Accept callbacks in Agent close and destroy (d1a406f982bda23a982c89a58ccc8ae049ed034e)
• Added closed and destroyed properties on Agent (#634)
• Allow overriding timeouts per requests (#679)
• Update deps (#675, 8158defc0ad159470bf52eacf5ff9e12005e11e5)
• Add undici mocking support (#587)
• Unify Client, Pool & Agent under Dispatcher (#544, #606, #620)
• Add connectTimeout (#619)
• Follow redirects (#603) (#769)
• Client lifecycle diagram (#567)
• Docs improvements and site (undici.nodejs.org) (#550, #565, #567, #582, #585, #596, 5095a2b3be8c7e338418905eec423fcc8a631ef9, #627)
• Reuse tls sessions across clients of a connection pool (#588)
• Add strictContentLength option to treat request content length mismatch as warning (#586)
• Connecting through a proxy (#568)
• Agent connect/disconnect events (#558)
• Use llhttp WASM build for http parsing (#564, #611, #642, #648, #680)
• Only append non empty search to path (e8ece2a7e8c5be2a8eef81d01f38a82a0a329dbb)
• Add factory arg to Pool and Agent (761738a045712840f24c2c2f2b3670797823ecf5)
• Use husky (#605)
• Add pr and issue templates (#608)
• Allow process to exit when no requests are pending (#772)
• Add data to parser errors (7a750ba998cbc4c125f747876536655c2f7b7c02)
• Try to re-use timer when possible (#729)
• Make request errors explicit (#777)

Fixes

• Don't emit 'disconnect' without preceding 'connect'(#771)
• Don't fail when response ends before request body (#709)
• Don't headersTimeout while writing request body (#646)
• Emit 'disconnect' after destroy() (#665)
• Refresh timeout timer on parser resume (#653)
• Agent deep copy options (#636)
• Kill socket on request abort (#689)
• Add more strict check for streams in util.isStream() (#628)
• Remove Node 10 support (#623)
• Remove the esm wrapper, rely on commonjs auto detection (#599)
• Always detach socket on upgrade (252b676756053bc8bcf70cff89cad33243a9c9e5)
• Invoke onUpgrade after detach (641e0185efe1090e412f6b9b7ec243ad18c52880)
• Missing client arg (#555)
• Reduce queueMicrotask scope (#572)
• Wait for queued handlers to run before onError (#548)
• Add BodyTimeoutError to error types (#546)
• Omit path in undici.request opts (ts) (#559)
• Don't queue if destroyed (3d002c135fcdbcccdf25120ef1fa8ab43e8228d5)
• Agent.dispatch catch error (8c0051f8d25badb252c4a13b7810fc9556f908e9)

Fixes:

• Remove semver major change from patch release.

Fixes:

• Wait for queued handlers to run before onError (#548).
• Add BodyTimeoutError to error types (#546).
• Agent. Check size instead of pending (https://github.com/nodejs/undici/commit/32753915dcb25dd151ca81e28d5646be8ec20968).

Improvements:

• Pool size & running (#535)

Fixes:

• Busy if pipeline is full (#541).

Improvements:

• Add support for Agent on Node 12 and lower (#533).

Improvements:

• Add close and destroy methods to Agent class (#521).
• Add Pool/Client.url (#527).
• Various Pool improvements (#525).
• Forward error on disconnect event (#524).

Improvements:

• Agent and global methods (#508).

📚 PR:

• fix: throw if passed keepAlive
• doc: fix grammar
• fix: don't fail socket if onComplete throws
• fix: throw if passed requestTimeout
• fix: improve not support arg error message
• fix: types
• perf: check aborted earlier
• perf: avoid closure capture
• Fix capitalization of 'errors' in types (#503)
• Two small grammar nits (#505)
• feat(pool): forward connect and disconnect events (#510)
• fix(types): Pool URL (#507)
• Do not run .mjs in test. Add npm test to CI. (#511)

Fixes:

• Replace socketTimeout with bodyTimeout (#460).
• Replace keepAlive option with pipelining: 0 (#459).
• Rename idleTimeout option to keepAliveTimeout (#461).
• Retry idempotent with original body (#471).
• Add writableNeedDrain support to Client.stream (#442).
• Free parser when detaching.
• Throw if passed maxKeepAliveTimeout, idleTimeout, or socketTimeout.

Improvements:

• Add trailers support to Client.request (#493).
• Misc refactoring.

Fixes:

• Fallback to url as servername (#490),

Fixes:

• Make keep-alive postfix optional (#477).
• Accept absolute urls as path (#468).

Improvements:

• Add types (#375).
• Update abort docs to native AbortController (#472).

Fixes:

• Free parser when detaching (6d92f142f2f7ed5796ceb405776593356011cf99)
• Retry idempotent body (#471)
• Host header missing port (60cc0cf4eeff1116e3ba082678fea8070afd1bbf)

📚 PR:

• cosmetics
• feat: allow pausing from onHeaders
• Remove node 14 benchmark results
• fix(core/request): handle header set to null (#453)
• test: support earliest versions in range in CI (#454)
• test: skip ESM test when ESM support not available (#455)
• fix(benchmarks): fix timeout errors (#457)
• Fix for node 12.19 (#458)

Fixes:

• Bad upgrade header (#451).
• Node 12.9 (#449).

Fixes:

• Handle socket handle error (#436).
• Always resume after complete if not destroy (1c628a996bd00fb959d0313b69964587709eeddc).
• Skip when running and keep alive (1c628a996bd00fb959d0313b69964587709eeddc).

Fixes:

• Socket back pressure memory leak (#435).
• Verify trailers (#433).

Fixes:

• Don't leak socket listener (#431).

Improvements

• Add proxy example (#425)

Fixes:

• Always resume in next tick (#420).
• Don't wait indefinitely on socket errors (#423).

Improvements:

• Add array support for request headers (#413).