https://github.com/node-geojson/geojson-stream

Stream features into and out of GeoJSON objects and Feature Collections.
https://github.com/node-geojson/geojson-stream

Last synced: 5 days ago
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Stream features into and out of GeoJSON objects and Feature Collections.

• Host: GitHub
• URL: https://github.com/node-geojson/geojson-stream
• Owner: node-geojson
• Created: 2013-10-17T17:45:31.000Z (about 11 years ago)
• Default Branch: master
• Last Pushed: 2019-01-16T22:47:34.000Z (almost 6 years ago)
• Last Synced: 2024-09-19T01:24:44.985Z (about 2 months ago)
• Language: JavaScript
• Homepage:
• Size: 8.79 KB
• Stars: 54
• Watchers: 54
• Forks: 12
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md

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• awesome-starred - node-geojson/geojson-stream - Stream features into and out of GeoJSON objects and Feature Collections. (others)

README

        
# geojson-stream

[![Greenkeeper badge](https://badges.greenkeeper.io/tmcw/geojson-stream.svg)](https://greenkeeper.io/)

[![build status](https://secure.travis-ci.org/tmcw/geojson-stream.svg)](http://travis-ci.org/tmcw/geojson-stream)

Stream features into and out of [GeoJSON](http://geojson.org/) objects

and Feature Collections. Little more than [JSONStream](https://github.com/dominictarr/JSONStream)

with pre-filled settings.

## usage

    npm install --save geojson-stream

## api

### `geojsonStream.stringify()`

Returns a transform stream that accepts GeoJSON Feature objects and emits

a stringified FeatureCollection.

### `geojsonStream.parse(mapFunc)`

Returns a transform stream that accepts a GeoJSON FeatureCollection as a stream

and emits Feature objects.

`mapFunc(feature, index)` is an optional function which takes a `Feature`, and its zero-based index in the `FeatureCollection` and returns either a `Feature`, or null/undefined 

if the feature should be omitted from output.

## example

```

const geojsonStream = require('geojson-stream');

const fs = require('fs');

const out = fs.createWriteStream('buildings-with-id.geojson');

fs

    .createReadStream(`buildings.geojson`)

    .pipe(geojsonStream.parse((building, index) => {

        if (building.geometry.coordinates === null) {

            return null;

        }

        building.id = index;

        return building;

    }))

    .pipe(geojsonStream.stringify())

    .pipe(out);

```