67 lines
1.8 KiB
Markdown
67 lines
1.8 KiB
Markdown
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## _readline_
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> Read a file line by line.
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## Install
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## Important. In node 10 there is a core module named readline. Please use linebyline instead, it is the same module just renamed:
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[Npm linebyline](https://www.npmjs.com/package/linebyline)
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```sh
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npm install linebyline
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```
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## Test
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```sh
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npm install .
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npm test
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```
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## What's this?
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Simple streaming readline module for NodeJS. Reads a file and buffers new lines emitting a _line_ event for each line.
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## Usage
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### Simple
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```js
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var readline = require('linebyline'),
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rl = readline('./somefile.txt');
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rl.on('line', function(line, lineCount, byteCount) {
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// do something with the line of text
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})
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.on('error', function(e) {
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// something went wrong
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});
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```
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### ASCII file decoding
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As the underlying `fs.createReadStream` doesn't care about the specific ASCII encoding of the file, an alternative way to decode the file is by telling the `readline` library to retain buffer and then decoding it using a converter (e.g. [`iconv-lite`](https://www.npmjs.com/package/iconv-lite)).
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```js
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var readline = require('linebyline'),
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rl = readline('./file-in-win1251.txt', {
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retainBuffer: true //tell readline to retain buffer
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});
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rl.on("line", function (data,linecount){
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var line = iconv.decode(data, 'win1251');
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// do something with the line of converted text
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});
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```
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##API
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## readLine(readingObject[, options])
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### Params:
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* `readingObject` - file path or stream object
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* `options` can include:
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* `maxLineLength` - override the default 4K buffer size (lines longer than this will not be read)
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* `retainBuffer` - avoid converting to String prior to emitting 'line' event; will pass raw buffer with encoded data to the callback
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### Return:
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* **EventEmitter**
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## License
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BSD © [Craig Brookes](http://craigbrookes.com/)
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