QWC2 Services

Certain QGIS Web Client (QWC2) components call web services, e.g. for generating permalinks.

This repository contains some sample services for testing.

The services are Flask applications, written in Python.

Proxy service

Proxies requests, adding the CORS headers

Run as

python proxy.py

API:

• Runs by default on http://localhost:5000
• GET, POST, PUT, DELETE: /?url=<url>&filename=<filename>
  • url: the url to proxy
  • filename: optional, if set it sets a content-disposition header with the specified filename

Permalink service

Generates and resolves compact permalinks.

Run as

python permalink.py

API:

• Runs by default on http://localhost:5001
• POST: /createpermalink?url=<url>
  • url: the url for which to generate a permalink
  • payload: a json document with additional state information
  • output: a json document: {permalink: <permalink_url>}
• GET: /resolvepermalink?key=<key>
  • key: the key query parameter of the permalink url
  • output: a json document: {query: <query_parameters>, state: <state>}
    • query_parameters: all query parameters of the URL passed to createpermalink
    • state: the state data passed as POST payload to createpermalink

Elevation service

Returns elevations.

Run as

ELEVATION_DATASET=<path/to/dtm.tif> python elevation.py

Requires GDAL Python bindings. python-gdal or python3-gdal packages on Debian/Ubuntu (Note: virtualenv creation requires --system-site-packages option).

API:

• Runs by default on http://localhost:5002
• GET: /getelevation?pos=<pos>&crs=<crs>
  • pos: the query position, as x,y
  • crs: the crs of the query position
  • output: a json document with the elevation in meters: {elevation: h}
• POST: /getheightprofile

  • payload: a json document as follows:

    {
        coordinates: [[x1,y1],[x2,y2],...],
        distances: [<dist_p1_p2>, <dist_p2_p3>, ...],
        projection: <EPSG:XXXX, projection of coordinates>,
        samples: <number of height samples to return>
    }
    

  • output: a json document with heights in meters: {elevations: [h1, h2, ...]}

Map info service

Returns additional information for the right-click map-info tooltip.

Run as

python mapInfo.py

API:

• Runs by default on http://localhost:5003
• GET: /?pos=<pos>&crs=<crs>
  • pos: the query position, as x,y
  • crs: the crs of the query position
  • output: a json document with map info for the specified position: {results: [[title1, value1], [title2, value2], ...]}

Feature report service

Generates a report (i.e. could be a PDF document) for a feature using the specified template.

Run as

python featureReport.py

API:

• Runs by default on http://localhost:5020
• GET: /?template=<template>&feature=<feature>
  • template: a template ID
  • feature: a feature ID
  • x: x coordinate of click which selected the feature
  • y: y coordinate of click which selected the feature
  • crs: crs of click coordinates
  • output: A blob with matching content-type