/StaticMapService

A micro service for rendering static map images in python using mapnik

Primary LanguagePythonMIT LicenseMIT

StaticMaps

This service lets you render static maps, using Mapnik to style them.

It accepts GeoJSON POST requests, and returns a styled map, rendered on a background.

Technology

This is designed to be used as a micro service and deployed as a Docker container.

It used Python, Django, and Mapnik.

Prebuilt Docker Images

Prebuilt docker images available as gaiagps/staticmapservice, If you want to add your own background, extend that image.

For an example service file for deploying with fleet see staticmaps@.service

For an example of how to add your own backgrounds see trailbehind/StaticMapService-extension-example

API

POST /{width}x{height}/{background}.{format}

Parameters

  • width and height: Integer, greater than 0, max value defaults to 1024, but can be configured with the MAX_IMAGE_DIMENSION environment variable
  • background: One of the installed background layers, or "none"

Post data - Required

GeoJSON data, with optional style data. Features and FeatureCollections are both supported.

Supported feature types
  • Point
  • Polygon
  • LineString
  • MultiLineString

MultiPoint, MultiPolygon and GeometryCollection features are not supported.

Styling

If a feature has a style element it will be used for styling, otherwise the properties element will be used for styling.

  • Point features Styling point features is not currently supported

  • LineString features

    • stroke Stroke color, default is red
    • stroke-width stroke width, default is 2
    • opacity range is 0-1.0
    • stroke-dasharray
    • stroke-linejoin one of: miter bevel round
    • stroke-linecap one of round butt square
    • smooth line smoothing, range is 0-1.0

  • Polygon features

    • Polygons are stroked using the same styling options as LineString features
    • fill fill color, default is red
    • opacity fill opacity, default is 0.6

See Mapnik LineSymbolizer reference and Mapnik PolygonSymbolizer reference for more info.

GET or POST /{bounds}/{width}x{height}/{background}.{format}

Parameters

  • bounds: A bounding box in w,s,e,n format. Example -120,38,-119,39. Bounding boxes that cross the anti-meridian are not currently supported

Post data - Optional

  • Same as above, but optional, and map will not be fit to data.

Backgrounds

Backgrounds can be any file that can be read by mapnik using GDAL. One background is installed by default, 'OSM' which uses the GDAL WMS driver to load tiles from OpenStreetMap.org. Any file placed in the staticMaps/baselayers/ directory is automatically loaded as a background/

Attribution

Images can have attribution text overlayed on the image. Attribution is set per background layer, in the staticMaps/baselayers/attribution.json file.

Example

curl -X POST -H "Content-Type: application/json" -d \
 '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"stroke":"#555555","stroke-width":2,"stroke-opacity":1,"fill":"#FED800","fill-opacity":0.5},"geometry":{"type":"Polygon","coordinates":[[[-122.49467253684996,37.77136775748373],[-122.49445796012878,37.771401680390476],[-122.49424338340759,37.77138471893906],[-122.493953704834,37.77131687309448],[-122.49380350112915,37.771189661968144],[-122.49377131462097,37.77101156602359],[-122.49380350112915,37.77079954648267],[-122.49388933181763,37.77067233446632],[-122.49405026435852,37.77057056469566],[-122.49428629875183,37.77054512223112],[-122.49451160430907,37.77062144959851],[-122.49474763870238,37.77079106568839],[-122.49483346939085,37.77102004679258],[-122.4948227405548,37.771223584956566],[-122.49467253684996,37.77136775748373]]]}},{"type":"Feature","properties":{"stroke-dasharray":[3,2]},"geometry":{"type":"LineString","coordinates":[[-122.49451160430907,37.77079954648267],[-122.4944633245468,37.77075290210209],[-122.49439358711244,37.77071473849609],[-122.49429166316986,37.77066809406202],[-122.49417901039122,37.770693536484245],[-122.49406099319457,37.77075714250155],[-122.49400734901428,37.77080378687947]]}},{"type":"Feature","geometry":{"type":"Point","coordinates":[-122.49448478221893,37.77111757556606]}},{"type":"Feature","geometry":{"type":"Point","coordinates":[-122.49414145946501,37.77113029670095]}}]}' \
 'http://192.168.99.100:8901/400x400/osm.png' > example.png

Example image

Credits

Inspired by the Mapbox Static map API