https://github.com/RangerMauve/through2-map-promise

A small promise-based wrapper for through2
https://github.com/RangerMauve/through2-map-promise

Last synced: about 2 months ago
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A small promise-based wrapper for through2

• Host: GitHub
• URL: https://github.com/RangerMauve/through2-map-promise
• Owner: RangerMauve
• License: isc
• Created: 2016-02-23T15:21:16.000Z (over 8 years ago)
• Default Branch: master
• Last Pushed: 2017-10-25T14:13:44.000Z (over 6 years ago)
• Last Synced: 2024-04-22T04:13:06.147Z (2 months ago)
• Language: JavaScript
• Size: 2.93 KB
• Stars: 3
• Watchers: 4
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Lists

• awesome-micro-npm-packages - through2-map-promise - A small promise-based wrapper for through2. (Modules / Stream)
• awesome-micro-npm-packages - through2-map-promise - A small promise-based wrapper for through2. (Modules / Stream)

README

        
# through2-map-promise

A small promise-based wrapper for through2. Allows you to easily map over data in a stream while using promises for flow control.

## Quickstart

```

npm install --save through2-map-promise

```

```javascript

var map = require("through2-map-promise");

var xtend = require("xtend");

// in an HTTP request handler

db.users.find({}).pipe(map.obj(function(user){

    var locationId = user.location;

    return db.locations.findOne({_id: locationId}).then(function(location){

        return xtend(user, {

            location: location

        });

    });

})).pipe(response);

```

## API

### `through2-map-promise([options,] [fn])`

Creates a transform stream which calls your transforming function, `fn`. You can throw within your function to automatically reject the promise and error-out the stream. `options` is the optional object that gets passed into [through2](https://github.com/rvagg/through2#options).

### `through2-map-promise.obj([options,] [fn])`

Same as the former, but the stream is created in objectMode

### `through2-map-promise.ctor([options,] [fn])`

Creates a constructor for your transform stream in case you want to be more efficient