{"id":29362905,"url":"https://github.com/stdlib-js/streams-node-debug-sink","last_synced_at":"2025-07-09T09:17:20.912Z","repository":{"id":57162756,"uuid":"377248519","full_name":"stdlib-js/streams-node-debug-sink","owner":"stdlib-js","description":"Writable stream for debugging stream pipelines.","archived":false,"fork":false,"pushed_at":"2025-06-02T01:16:21.000Z","size":1520,"stargazers_count":3,"open_issues_count":0,"forks_count":0,"subscribers_count":3,"default_branch":"main","last_synced_at":"2025-06-02T11:19:31.045Z","etag":null,"topics":["debug","inspect","javascript","log","monitor","node","node-js","nodejs","sink","sniff","spy","stdlib","stream","streams","tap","util","utilities","utility","utils","writable"],"latest_commit_sha":null,"homepage":"https://github.com/stdlib-js/stdlib","language":"JavaScript","has_issues":false,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"apache-2.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/stdlib-js.png","metadata":{"files":{"readme":"README.md","changelog":"CHANGELOG.md","contributing":"CONTRIBUTING.md","funding":null,"license":"LICENSE","code_of_conduct":"CODE_OF_CONDUCT.md","threat_model":null,"audit":null,"citation":"CITATION.cff","codeowners":null,"security":"SECURITY.md","support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null,"zenodo":null},"funding":{"github":["stdlib-js"],"open_collective":"stdlib","tidelift":"npm/@stdlib/stdlib"}},"created_at":"2021-06-15T17:47:18.000Z","updated_at":"2025-06-02T01:02:57.000Z","dependencies_parsed_at":"2023-10-05T09:09:13.376Z","dependency_job_id":"a0e593c4-6594-4dd0-8ffc-beaa4325487c","html_url":"https://github.com/stdlib-js/streams-node-debug-sink","commit_stats":{"total_commits":48,"total_committers":1,"mean_commits":48.0,"dds":0.0,"last_synced_commit":"4cd7b70090c7da7cd6a17eba3b321fb73749d64d"},"previous_names":[],"tags_count":22,"template":false,"template_full_name":null,"purl":"pkg:github/stdlib-js/streams-node-debug-sink","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstreams-node-debug-sink","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstreams-node-debug-sink/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstreams-node-debug-sink/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstreams-node-debug-sink/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/stdlib-js","download_url":"https://codeload.github.com/stdlib-js/streams-node-debug-sink/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstreams-node-debug-sink/sbom","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":263476510,"owners_count":23472593,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["debug","inspect","javascript","log","monitor","node","node-js","nodejs","sink","sniff","spy","stdlib","stream","streams","tap","util","utilities","utility","utils","writable"],"created_at":"2025-07-09T09:17:18.902Z","updated_at":"2025-07-09T09:17:20.907Z","avatar_url":"https://github.com/stdlib-js.png","language":"JavaScript","funding_links":["https://github.com/sponsors/stdlib-js","https://opencollective.com/stdlib","https://tidelift.com/funding/github/npm/@stdlib/stdlib"],"categories":[],"sub_categories":[],"readme":"\u003c!--\n\n@license Apache-2.0\n\nCopyright (c) 2018 The Stdlib Authors.\n\nLicensed under the Apache License, Version 2.0 (the \"License\");\nyou may not use this file except in compliance with the License.\nYou may obtain a copy of the License at\n\n   http://www.apache.org/licenses/LICENSE-2.0\n\nUnless required by applicable law or agreed to in writing, software\ndistributed under the License is distributed on an \"AS IS\" BASIS,\nWITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\nSee the License for the specific language governing permissions and\nlimitations under the License.\n\n--\u003e\n\n\n\u003cdetails\u003e\n  \u003csummary\u003e\n    About stdlib...\n  \u003c/summary\u003e\n  \u003cp\u003eWe believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.\u003c/p\u003e\n  \u003cp\u003eThe library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.\u003c/p\u003e\n  \u003cp\u003eWhen you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.\u003c/p\u003e\n  \u003cp\u003eTo join us in bringing numerical computing to the web, get started by checking us out on \u003ca href=\"https://github.com/stdlib-js/stdlib\"\u003eGitHub\u003c/a\u003e, and please consider \u003ca href=\"https://opencollective.com/stdlib\"\u003efinancially supporting stdlib\u003c/a\u003e. We greatly appreciate your continued support!\u003c/p\u003e\n\u003c/details\u003e\n\n# Debug Stream\n\n[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] \u003c!-- [![dependencies][dependencies-image]][dependencies-url] --\u003e\n\n\u003e [Writable stream][writable-stream] for [debugging][node-debug] stream pipelines.\n\n\u003csection class=\"installation\"\u003e\n\n## Installation\n\n```bash\nnpm install @stdlib/streams-node-debug-sink\n```\n\nAlternatively,\n\n-   To load the package in a website via a `script` tag without installation and bundlers, use the [ES Module][es-module] available on the [`esm`][esm-url] branch (see [README][esm-readme]).\n-   If you are using Deno, visit the [`deno`][deno-url] branch (see [README][deno-readme] for usage intructions).\n-   For use in Observable, or in browser/node environments, use the [Universal Module Definition (UMD)][umd] build available on the [`umd`][umd-url] branch (see [README][umd-readme]).\n\nThe [branches.md][branches-url] file summarizes the available branches and displays a diagram illustrating their relationships.\n\nTo view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.\n\n\u003c/section\u003e\n\n\u003csection class=\"usage\"\u003e\n\n## Usage\n\n```javascript\nvar debugSinkStream = require( '@stdlib/streams-node-debug-sink' );\n```\n\n\u003ca name=\"debug-sink-stream\"\u003e\u003c/a\u003e\n\n#### debugSinkStream( \\[options,] \\[clbk] )\n\nCreates a [writable stream][writable-stream] for [debugging][node-debug] stream pipelines.\n\n```javascript\nvar ENV = require( '@stdlib/process-env' );\n\n// Set the `DEBUG` environment variable...\nENV.DEBUG = '*';\n\nvar stream = debugSinkStream({\n    'name': 'my-stream'\n});\n\nstream.write( 'a' );\nstream.write( 'b' );\nstream.write( 'c' );\nstream.end();\n```\n\nThe function accepts the following `options`:\n\n-   **name**: [debug][node-debug] namespace.\n-   **objectMode**: specifies whether a [stream][stream] should operate in [objectMode][object-mode]. Default: `false`.\n-   **highWaterMark**: specifies the `Buffer` level at which `write()` calls start returning `false`.\n-   **decodeStrings**: specifies whether to encode strings as `Buffer` objects before writing data to a returned [stream][stream]. Default: `true`.\n-   **defaultEncoding**: default encoding when not explicitly specified when writing data. Default: `'utf8'`.\n\nTo set [stream][stream] `options`,\n\n```javascript\nvar opts = {\n    'name': 'my-app',\n    'objectMode': true,\n    'highWaterMark': 64,\n    'decodeStrings': false,\n    'defaultEncoding': 'utf8'\n};\n\nvar stream = debugSinkStream( opts );\n```\n\nBy default, each `chunk` is logged as a JSON stringified `string`, along with the `chunk` index. For more control over logging behavior, provide a `callback`.\n\n```javascript\nfunction logger( debug, chunk, idx ) {\n    debug( 'Received a new chunk...' );\n    debug( 'Beep: %s', chunk.beep );\n    debug( 'Boop: %s', chunk.boop );\n}\n\nvar opts = {\n    'name': 'my-pipeline'\n};\n\nvar stream = debugSinkStream( opts, logger );\n```\n\n#### debugSinkStream.factory( \\[options] )\n\nReturns a `function` for creating [streams][writable-stream] which are identically configured according to provided `options`.\n\n```javascript\nvar opts = {\n    'objectMode': true,\n    'highWaterMark': 64\n};\n\nvar factory = debugSinkStream.factory( opts );\n```\n\nThis method accepts the same `options` as [`debugSinkStream()`](#debug-sink-stream), **except** for `name`, which must be provided **explicitly**.\n\n##### factory( name\\[, clbk] )\n\nCreates a [debug][node-debug] stream.\n\n```javascript\nvar factory = debugSinkStream.factory();\n\nvar streams = [];\nvar i;\n\n// Assign each stream to a separate debug namespace...\nfor ( i = 0; i \u003c 10; i++ ) {\n    streams.push( factory( 'stream '+i ) );\n}\n```\n\n#### debugSinkStream.objectMode( \\[options,] \\[clbk] )\n\nThis method is a convenience function to create [streams][stream] which **always** operate in [objectMode][object-mode].\n\n```javascript\nvar stream = debugSinkStream.objectMode({\n    'name': 'beep-boop'\n});\n\nstream.write({\n    'value': 'a'\n});\nstream.write({\n    'value': 'b'\n});\nstream.write({\n    'value': 'c'\n});\nstream.end();\n```\n\nThis method accepts the same `options` as [`debugSinkStream()`](#debug-sink-stream); however, the method will **always** override the [objectMode][object-mode] option in `options`.\n\n\u003c/section\u003e\n\n\u003c!-- /.usage --\u003e\n\n\u003csection class=\"notes\"\u003e\n\n## Notes\n\n-   If the [`DEBUG`][node-debug] environment variable is **not** set, no data is logged.\n-   Providing a `name` option is **strongly** encouraged, as the [`DEBUG`][node-debug] environment variable can be used to filter debuggers.\n\n\u003c/section\u003e\n\n\u003c!-- /.notes --\u003e\n\n\u003csection class=\"examples\"\u003e\n\n## Examples\n\n\u003c!-- eslint no-undef: \"error\" --\u003e\n\n```javascript\nvar parseJSON = require( '@stdlib/utils-parse-json' );\nvar transformFactory = require( '@stdlib/streams-node-transform' ).factory;\nvar debug = require( '@stdlib/streams-node-debug-sink' ).objectMode;\n\nfunction parse( chunk, enc, clbk ) {\n    clbk( null, parseJSON( chunk ) );\n}\n\nfunction pluck( chunk, enc, clbk ) {\n    clbk( null, chunk.value );\n}\n\nfunction square( chunk, enc, clbk ) {\n    var v = +chunk;\n    clbk( null, v*v );\n}\n\nfunction toStr( chunk, enc, clbk ) {\n    clbk( null, chunk.toString() );\n}\n\nfunction join( chunk, enc, clbk ) {\n    clbk( null, chunk+'\\n' );\n}\n\n// Create a factory for generating streams running in `objectMode`:\nvar tStream = transformFactory({\n    'objectMode': true\n});\n\n// Create streams for each transform:\nvar s1 = tStream( parse );\nvar s2 = tStream( pluck );\nvar s3 = tStream( square );\nvar s4 = tStream( toStr );\nvar s5 = tStream( join );\n\n// Create a writable stream for debugging the result of the transformations:\nvar ds = debug({\n    'name': 'debugger'\n});\n\n// Create the pipeline:\ns1.pipe( s2 )\n    .pipe( s3 )\n    .pipe( s4 )\n    .pipe( s5 )\n    .pipe( ds );\n\n// Write data to the pipeline...\nvar v;\nvar i;\nfor ( i = 0; i \u003c 100; i++ ) {\n    v = '{\"value\":'+i+'}';\n    s1.write( v, 'utf8' );\n}\ns1.end();\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.examples --\u003e\n\n\u003c!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. --\u003e\n\n\u003csection class=\"related\"\u003e\n\n* * *\n\n## See Also\n\n-   \u003cspan class=\"package-name\"\u003e[`@stdlib/streams-node/debug`][@stdlib/streams/node/debug]\u003c/span\u003e\u003cspan class=\"delimiter\"\u003e: \u003c/span\u003e\u003cspan class=\"description\"\u003etransform stream for debugging stream pipelines.\u003c/span\u003e\n-   \u003cspan class=\"package-name\"\u003e[`@stdlib/streams-node/inspect-sink`][@stdlib/streams/node/inspect-sink]\u003c/span\u003e\u003cspan class=\"delimiter\"\u003e: \u003c/span\u003e\u003cspan class=\"description\"\u003ewritable stream for inspecting streamed data.\u003c/span\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.related --\u003e\n\n\u003c!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\n\u003csection class=\"main-repo\" \u003e\n\n* * *\n\n## Notice\n\nThis package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.\n\nFor more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].\n\n#### Community\n\n[![Chat][chat-image]][chat-url]\n\n---\n\n## License\n\nSee [LICENSE][stdlib-license].\n\n\n## Copyright\n\nCopyright \u0026copy; 2016-2025. The Stdlib [Authors][stdlib-authors].\n\n\u003c/section\u003e\n\n\u003c!-- /.stdlib --\u003e\n\n\u003c!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"links\"\u003e\n\n[npm-image]: http://img.shields.io/npm/v/@stdlib/streams-node-debug-sink.svg\n[npm-url]: https://npmjs.org/package/@stdlib/streams-node-debug-sink\n\n[test-image]: https://github.com/stdlib-js/streams-node-debug-sink/actions/workflows/test.yml/badge.svg?branch=main\n[test-url]: https://github.com/stdlib-js/streams-node-debug-sink/actions/workflows/test.yml?query=branch:main\n\n[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/streams-node-debug-sink/main.svg\n[coverage-url]: https://codecov.io/github/stdlib-js/streams-node-debug-sink?branch=main\n\n\u003c!--\n\n[dependencies-image]: https://img.shields.io/david/stdlib-js/streams-node-debug-sink.svg\n[dependencies-url]: https://david-dm.org/stdlib-js/streams-node-debug-sink/main\n\n--\u003e\n\n[chat-image]: https://img.shields.io/gitter/room/stdlib-js/stdlib.svg\n[chat-url]: https://app.gitter.im/#/room/#stdlib-js_stdlib:gitter.im\n\n[stdlib]: https://github.com/stdlib-js/stdlib\n\n[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors\n\n[umd]: https://github.com/umdjs/umd\n[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules\n\n[deno-url]: https://github.com/stdlib-js/streams-node-debug-sink/tree/deno\n[deno-readme]: https://github.com/stdlib-js/streams-node-debug-sink/blob/deno/README.md\n[umd-url]: https://github.com/stdlib-js/streams-node-debug-sink/tree/umd\n[umd-readme]: https://github.com/stdlib-js/streams-node-debug-sink/blob/umd/README.md\n[esm-url]: https://github.com/stdlib-js/streams-node-debug-sink/tree/esm\n[esm-readme]: https://github.com/stdlib-js/streams-node-debug-sink/blob/esm/README.md\n[branches-url]: https://github.com/stdlib-js/streams-node-debug-sink/blob/main/branches.md\n\n[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/streams-node-debug-sink/main/LICENSE\n\n[stream]: https://nodejs.org/api/stream.html\n\n[object-mode]: https://nodejs.org/api/stream.html#stream_object_mode\n\n[writable-stream]: https://nodejs.org/api/stream.html\n\n[node-debug]: https://www.npmjs.com/package/debug\n\n\u003c!-- \u003crelated-links\u003e --\u003e\n\n[@stdlib/streams/node/debug]: https://github.com/stdlib-js/streams-node-debug\n\n[@stdlib/streams/node/inspect-sink]: https://github.com/stdlib-js/streams-node-inspect-sink\n\n\u003c!-- \u003c/related-links\u003e --\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.links --\u003e\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Fstreams-node-debug-sink","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fstdlib-js%2Fstreams-node-debug-sink","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Fstreams-node-debug-sink/lists"}