gj-union-web-app

Microservice for computing the union of GeoJSON features

API usage

POST JSON data of this format:

{
  "geometries": [
    {
      "type": "Polygon",
      "coordinates": [
        [
          [
            38.814697265625,
            -6.817352822622144
          ],
          [
            39.9847412109375,
            -6.817352822622144
          ],
          [
            39.9847412109375,
            -5.413679614940935
          ],
          [
            38.814697265625,
            -5.413679614940935
          ],
          [
            38.814697265625,
            -6.817352822622144
          ]
        ]
      ]
    },
    {
      "type": "Polygon",
      "coordinates": [
        [
          [
            39.287109375,
            -5.626919311742117
          ],
          [
            40.1715087890625,
            -5.626919311742117
          ],
          [
            40.1715087890625,
            -4.691404288203818
          ],
          [
            39.287109375,
            -4.691404288203818
          ],
          [
            39.287109375,
            -5.626919311742117
          ]
        ]
      ]
    }
  ]
}

and get the union GeoJSON back, brought to you by Shapely / libgeos.

Deployment

... is very easy thanks to Zappa: Remove the .in from zappa_config.toml.in and ajust to your needs. Then zappa deploy development.

Why?

Computing the union of complex polygons is expensive. If an app needs to do that many times, you might be better off offloading this to a microservice that can run many times in parallel and caches nicely.