# History | Version | Release date | |-------------------------------------------------------------------------------------------------------------|----------------| | [5.2.3](#523-2024-07-11) | July 2024 | | [5.2.2](#522-2024-02-05) | February 2024 | | [5.2.1](#521-2023-08-01) | August 2023 | | [5.2.0](#520-2023-07-31) | July 2023 | | [5.1.0](#510-2023-06-11) | June 2023 | | [5.0.7](#507-2023-05-24) | May 2023 | | [5.0.6](#506-2023-01-16) | January 2023 | | [5.0.5](#505-2023-01-06) | January 2023 | | [5.0.4](#504-2022-04-30) | April 2022 | | [5.0.3](#503-2022-01-17) | January 2022 | | [5.0.2](#502-2021-11-14) | November 2021 | | [5.0.1](#501-2021-10-15) | October 2021 | | [**5.0.0**](#500-2021-10-04) (major: TypeScript rewrite) | October 2021 | | [4.0.3](#403-2021-08-29) | August 2021 | | [4.0.2](#402-2020-12-07) | December 2020 | | [2.2.1](#221-2020-09-30) (from the [2.2.x](https://github.com/socketio/engine.io-parser/tree/2.2.x) branch) | September 2020 | | [4.0.1](#401-2020-09-10) | September 2020 | | [**4.0.0**](#400-2020-09-08) (major: Engine.IO v4) | September 2020 | | [2.2.0](#220-2019-09-13) | September 2019 | # Release notes ## [5.2.3](https://github.com/socketio/socket.io/compare/engine.io-parser@5.2.2...engine.io-parser@5.2.3) (2024-07-11) ### Bug Fixes * do not expose the TransformStream type ([f9cb983](https://github.com/socketio/socket.io/commit/f9cb983ab7050c0a1630cfc97eb30f2dd807186b)) ## [5.2.2](https://github.com/socketio/engine.io-parser/compare/5.2.1...5.2.2) (2024-02-05) ### Bug Fixes * **typescript:** properly import the TransformStream type ([0305b4a](https://github.com/socketio/engine.io-parser/commit/0305b4a7a597e0f070ce8ea17106121f9ab369bc)) ## [5.2.1](https://github.com/socketio/engine.io-parser/compare/5.2.0...5.2.1) (2023-08-01) The format of the WebTransport frame has been slightly updated. ## [5.2.0](https://github.com/socketio/engine.io-parser/compare/5.1.0...5.2.0) (2023-07-31) ### Features * prepend a header to each WebTransport chunk ([6142324](https://github.com/socketio/engine.io-parser/commit/6142324fa61204393028f3f58f336d053030ea5f)) ## [5.1.0](https://github.com/socketio/engine.io-parser/compare/5.0.7...5.1.0) (2023-06-11) ### Features * implement WebTransport-related encoding/decoding ([bed70a4](https://github.com/socketio/engine.io-parser/commit/bed70a4f2598ebdf96d8ccc1b5d838b1a77a4290)) ## [5.0.7](https://github.com/socketio/engine.io-parser/compare/5.0.6...5.0.7) (2023-05-24) The CommonJS build now includes the TypeScript declarations too, in order to be compatible the "node16" moduleResolution. ## [5.0.6](https://github.com/socketio/engine.io-parser/compare/5.0.5...5.0.6) (2023-01-16) The `compile` script was not run before publishing `5.0.5`, so the esm build did not include the latest changes. ## [5.0.5](https://github.com/socketio/engine.io-parser/compare/5.0.4...5.0.5) (2023-01-06) ### Bug Fixes * properly encode empty buffer in base64 encoding ([#131](https://github.com/socketio/engine.io-parser/issues/131)) ([351ba82](https://github.com/socketio/engine.io-parser/commit/351ba8245b1aac795646d7e7a9001c8e1d0cc9f2)) ## [5.0.4](https://github.com/socketio/engine.io-parser/compare/5.0.3...5.0.4) (2022-04-30) ### Bug Fixes * add missing file extension for ESM import ([a421bbe](https://github.com/socketio/engine.io-parser/commit/a421bbec7bf43c567c49c608dee604872f6db823)) * **typings:** update the type of RawData ([039b45c](https://github.com/socketio/engine.io-parser/commit/039b45cc65b50acc1f9da42ad605eaccb8ccbcde)) ## [5.0.3](https://github.com/socketio/engine.io-parser/compare/5.0.2...5.0.3) (2022-01-17) ## [5.0.2](https://github.com/socketio/engine.io-parser/compare/5.0.1...5.0.2) (2021-11-14) ### Bug Fixes * add package name in nested package.json ([7e27159](https://github.com/socketio/engine.io-parser/commit/7e271596c3305fb4e4a9fbdcc7fd442e8ff71200)) * fix vite build for CommonJS users ([5f22ed0](https://github.com/socketio/engine.io-parser/commit/5f22ed0527cc80aa0cac415dfd12db2f94f0a855)) ## [5.0.1](https://github.com/socketio/engine.io-parser/compare/5.0.0...5.0.1) (2021-10-15) ### Bug Fixes * fix vite build ([900346e](https://github.com/socketio/engine.io-parser/commit/900346ea34ddc178d80eaabc8ea516d929457855)) ## [5.0.0](https://github.com/socketio/engine.io-parser/compare/4.0.3...5.0.0) (2021-10-04) This release includes the migration to TypeScript. The major bump is due to the new "exports" field in the package.json file. See also: https://nodejs.org/api/packages.html#packages_package_entry_points ## [4.0.3](https://github.com/socketio/engine.io-parser/compare/4.0.2...4.0.3) (2021-08-29) ### Bug Fixes * respect the offset and length of TypedArray objects ([6d7dd76](https://github.com/socketio/engine.io-parser/commit/6d7dd76130690afda6c214d5c04305d2bbc4eb4d)) ## [4.0.2](https://github.com/socketio/engine.io-parser/compare/4.0.1...4.0.2) (2020-12-07) ### Bug Fixes * add base64-arraybuffer as prod dependency ([2ccdeb2](https://github.com/socketio/engine.io-parser/commit/2ccdeb277955bed8742a29f2dcbbf57ca95eb12a)) ## [2.2.1](https://github.com/socketio/engine.io-parser/compare/2.2.0...2.2.1) (2020-09-30) ## [4.0.1](https://github.com/socketio/engine.io-parser/compare/4.0.0...4.0.1) (2020-09-10) ### Bug Fixes * use a terser-compatible representation of the separator ([886f9ea](https://github.com/socketio/engine.io-parser/commit/886f9ea7c4e717573152c31320f6fb6c6664061b)) ## [4.0.0](https://github.com/socketio/engine.io-parser/compare/v4.0.0-alpha.1...4.0.0) (2020-09-08) This major release contains the necessary changes for the version 4 of the Engine.IO protocol. More information about the new version can be found [there](https://github.com/socketio/engine.io-protocol#difference-between-v3-and-v4). Encoding changes between v3 and v4: - encodePacket with string - input: `{ type: "message", data: "hello" }` - output in v3: `"4hello"` - output in v4: `"4hello"` - encodePacket with binary - input: `{ type: 'message', data: }` - output in v3: `` - output in v4: `` - encodePayload with strings - input: `[ { type: 'message', data: 'hello' }, { type: 'message', data: '€€€' } ]` - output in v3: `"6:4hello4:4€€€"` - output in v4: `"4hello\x1e4€€€"` - encodePayload with string and binary - input: `[ { type: 'message', data: 'hello' }, { type: 'message', data: } ]` - output in v3: `` - output in v4: `"4hello\x1ebAQID"` Please note that the parser is now dependency-free! This should help reduce the size of the browser bundle. ### Bug Fixes * keep track of the buffer initial length ([8edf2d1](https://github.com/socketio/engine.io-parser/commit/8edf2d1478026da442f519c2d2521af43ba01832)) ### Features * restore the upgrade mechanism ([6efedfa](https://github.com/socketio/engine.io-parser/commit/6efedfa0f3048506a4ba99e70674ddf4c0732e0c)) ## [4.0.0-alpha.1](https://github.com/socketio/engine.io-parser/compare/v4.0.0-alpha.0...v4.0.0-alpha.1) (2020-05-19) ### Features * implement the version 4 of the protocol ([cab7db0](https://github.com/socketio/engine.io-parser/commit/cab7db0404e0a69f86a05ececd62c8c31f4d97d5)) ## [4.0.0-alpha.0](https://github.com/socketio/engine.io-parser/compare/2.2.0...v4.0.0-alpha.0) (2020-02-04) ### Bug Fixes * properly decode binary packets ([5085373](https://github.com/socketio/engine.io-parser/commit/50853738e0c6c16f9cee0d7887651155f4b78240)) ### Features * remove packet type when encoding binary packets ([a947ae5](https://github.com/socketio/engine.io-parser/commit/a947ae59a2844e4041db58ff36b270d1528b3bee)) ### BREAKING CHANGES * the packet containing binary data will now be sent without any transformation Protocol v3: { type: 'message', data: } => Protocol v4: { type: 'message', data: } => ## [2.2.0](https://github.com/socketio/engine.io-parser/compare/2.1.3...2.2.0) (2019-09-13) * [refactor] Use `Buffer.allocUnsafe` instead of `new Buffer` (#104) ([aedf8eb](https://github.com/socketio/engine.io-parser/commit/aedf8eb29e8bf6aeb5c6cc68965d986c4c958ae2)), closes [#104](https://github.com/socketio/engine.io-parser/issues/104) ### BREAKING CHANGES * drop support for Node.js 4 (since Buffer.allocUnsafe was added in v5.10.0) Reference: https://nodejs.org/docs/latest/api/buffer.html#buffer_class_method_buffer_allocunsafe_size