| 1 |
|
| 2 | # Stream transformation for Node.js and the web
|
| 3 |
|
| 4 | [](https://github.com/adaltas/node-csv/actions)
|
| 5 | [](https://www.npmjs.com/package/stream-transform)
|
| 6 | [](https://www.npmjs.com/package/stream-transform)
|
| 7 |
|
| 8 | The [`stream-transform` project](https://csv.js.org/transform/) is a simple object transformation framework. It is part of the [CSV project](https://csv.js.org/).
|
| 9 |
|
| 10 | The Node.js [`stream.Transform` API](http://nodejs.org/api/stream.html#stream_class_stream_transform) is implemented for scalability. The callback-based and sync APIs are also available for convenience. It is both easy to use and powerful.
|
| 11 |
|
| 12 | ## Documentation
|
| 13 |
|
| 14 | * [Project homepage](https://csv.js.org/transform/)
|
| 15 | * [API](https://csv.js.org/transform/api/)
|
| 16 | * [Options](https://csv.js.org/transform/options/)
|
| 17 | * [Handler](https://csv.js.org/transform/handler/)
|
| 18 | * [State properties](https://csv.js.org/transform/state/)
|
| 19 | * [Examples](https://csv.js.org/transform/examples/)
|
| 20 |
|
| 21 | ## Main features
|
| 22 |
|
| 23 | * Extends the native Node.js [transform stream API](http://nodejs.org/api/stream.html#stream_class_stream_transform)
|
| 24 | * Simplicity with the optional callback and sync API
|
| 25 | * Pipe transformations between readable and writable streams
|
| 26 | * Synchronous versus asynchronous user functions
|
| 27 | * Sequential and parallel execution
|
| 28 | * Accept object, array or JSON as input and output
|
| 29 | * Sequential or user-defined concurrent execution
|
| 30 | * Skip and multiply records
|
| 31 | * Alter or clone input records
|
| 32 | * MIT License
|
| 33 |
|
| 34 | ## Usage
|
| 35 |
|
| 36 | Run `npm install csv` to install the full csv module or run `npm install csv-transform` if you are only interested by the CSV stringifier.
|
| 37 |
|
| 38 | The module is built on the Node.js Stream API. Use the callback and sync APIs for simplicity or the stream based API for scalability.
|
| 39 |
|
| 40 | ## Example
|
| 41 |
|
| 42 | The [API](https://csv.js.org/transform/api/) is available in multiple flavors. This example illustrates the sync API.
|
| 43 |
|
| 44 | ```js
|
| 45 | import { transform } from 'stream-transform/sync';
|
| 46 | import assert from 'assert';
|
| 47 |
|
| 48 | const records = transform([
|
| 49 | [ 'a', 'b', 'c', 'd' ],
|
| 50 | [ '1', '2', '3', '4' ]
|
| 51 | ], function(record){
|
| 52 | record.push(record.shift());
|
| 53 | return record;
|
| 54 | });
|
| 55 |
|
| 56 | assert.deepEqual(records, [
|
| 57 | [ 'b', 'c', 'd', 'a' ],
|
| 58 | [ '2', '3', '4', '1' ]
|
| 59 | ]);
|
| 60 | ```
|
| 61 |
|
| 62 | ## Development
|
| 63 |
|
| 64 | Tests are executed with mocha. To install it, simple run `npm install` followed by `npm test`. It will install mocha and its dependencies in your project "node_modules" directory and run the test suite. The tests run against the CoffeeScript source files.
|
| 65 |
|
| 66 | To generate the JavaScript files, run `npm run coffee`.
|
| 67 |
|
| 68 | The test suite is run online with [Travis](http://travis-ci.org/wdavidw/node-stream-transform). See the [Travis definition file](https://github.com/adaltas/node-stream-transform/blob/master/.travis.yml) to view the tested Node.js version.
|
| 69 |
|
| 70 | ## Contributors
|
| 71 |
|
| 72 | The project is sponsored by [Adaltas](https://www.adaltas.com), an Big Data consulting firm based in Paris, France.
|
| 73 |
|
| 74 | * David Worms: <https://github.com/wdavidw>
|