https://github.com/mapbox/shp-write
create and write to shapefiles in pure javascript
https://github.com/mapbox/shp-write
Last synced: about 2 months ago
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create and write to shapefiles in pure javascript
- Host: GitHub
- URL: https://github.com/mapbox/shp-write
- Owner: mapbox
- License: bsd-3-clause
- Created: 2013-09-25T17:42:09.000Z (over 11 years ago)
- Default Branch: master
- Last Pushed: 2025-02-18T19:42:26.000Z (4 months ago)
- Last Synced: 2025-03-18T13:57:26.634Z (3 months ago)
- Language: JavaScript
- Homepage:
- Size: 202 KB
- Stars: 304
- Watchers: 125
- Forks: 192
- Open Issues: 34
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
# @mapbox/shp-write
Writes shapefile in pure javascript. Uses [dbf](https://github.com/tmcw/dbf)
for the data component, and [jsZIP](http://stuk.github.io/jszip/) to generate downloads in-browser.
> [!IMPORTANT]
> **The package location for this repo has changed!**
>
> tl;dr: `shp-write` -> [`@mapbox/shp-write`](https://www.npmjs.com/package/@mapbox/shp-write)
## Usage
NPM
npm install --save @mapbox/shp-write
Yarn
yarn add @mapbox/shp-write
Browser
https://unpkg.com/@mapbox/shp-write@latest/shpwrite.js
## Caveats
- Requires a capable fancy modern browser with [Typed Arrays](http://caniuse.com/#feat=typedarrays)
support
- Supports geometries: `Point`, `LineString`, `Polygon`, `MultiLineString`, `MultiPolygon`
- Tabular-style properties export with [10 character field name length limit](https://en.wikipedia.org/wiki/Shapefile#:~:text=Maximum%20length%20of%20field%20names%20is%2010%20characters)
- Uses jsZip for ZIP files, but [compression is buggy](https://github.com/Stuk/jszip/issues/53) so it uses STORE instead of DEFLATE.
## Example
```js
var shpwrite = require("@mapbox/shp-write");
const geoJSON = {
type: "FeatureCollection",
features: [
{
type: "Feature",
geometry: {
type: "Point",
coordinates: [0, 0],
},
properties: {
name: "Foo",
},
},
{
type: "Feature",
geometry: {
type: "Point",
coordinates: [0, 10],
},
properties: {
name: "Bar",
},
},
],
};
// Optional custom options passed to the underlying `zip` call
const options = {
folder: "my_internal_shapes_folder",
filename: "my_zip_filename",
outputType: "blob",
compression: "DEFLATE",
types: {
point: "mypoints",
polygon: "mypolygons",
polyline: "mylines",
},
};
const zipData = shpwrite.zip(geoJSON,options);
```
## Custom .prj file
To pass a custom [WKT string](http://www.opengeospatial.org/standards/wkt-crs) in the .prj file to define a different projection the prj option can be used:
```js
var options = {
prj: 'PROJCS["Amersfoort / RD New",GEOGCS["Amersfoort",DATUM["D_Amersfoort",SPHEROID["Bessel_1841",6377397.155,299.1528128]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],PROJECTION["Stereographic_North_Pole"],PARAMETER["standard_parallel_1",52.15616055555555],PARAMETER["central_meridian",5.38763888888889],PARAMETER["scale_factor",0.9999079],PARAMETER["false_easting",155000],PARAMETER["false_northing",463000],UNIT["Meter",1]]'
}
```
## API
### `write(data, geometrytype, geometries, callback)`
Generates a shapefile and calls the callback with err and an object containing shp, shx, and dbf DataViews.
* data: Array of objects for each row of data.
* geometrytype: The OGC standard geometry type (e.g., POINT).
* geometries: List of geometries as bare coordinate arrays.
* callback: Function to handle the generated DataViews.
```js
shpwrite.write(data, geometrytype, geometries, (err, result) => {
// result is equal to
// {
// shp: DataView(),
// shx: DataView(),
// dbf: DataView()
// }
if (err) throw err;
console.log(result);
});
```
### `zip(geojson, [options])`
Generate a ArrayBuffer of a zipped shapefile, dbf, and prj, from a GeoJSON
object.
### `download(geojson, [options])`
> [!WARNING]
> This is now marked as deprecated because it applies to browsers only and the
user should instead rely on an external library for this functionality like
`file-saver` or `downloadjs`
Given a [GeoJSON](http://geojson.org/) FeatureCollection as an object, converts convertible features into Shapefiles and triggers a download. `options` is passed to the underlying `zip` call.
## Other Implementations
- https://code.google.com/p/pyshp/
## Reference
- http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf
## Contributors
- Nick Baugh
- Charles Richardson