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QGIS

QGIS is an Open Source Desktop GIS platform. Since its inception in 2002, it's become a staple in the geospatial data stack. Download QGIS here.

Fused UDFs can be configured to return raster tile and vector data in formats that QGIS can load. The QGIS User Guide describes how QGIS handles different data types. This walkthrough shows how to generate URL endpoints to easily load data into QGIS.

1. Generate a signed URL for a UDF​

First, create a UDF and generate an HTTP endpoint.

2. Load data into QGIS​

QGIS supports loading data from UDFs called as both File and Tile.

Raster Tiles​

Dynamically render XYZ raster tiles on the QGIS map.

As an example, the "Sentinel Tile Example" public UDF returns an XYZ tile URL of NDVI from the Sentinel dataset. Create a new instance of it on your workbench, generate a shared URL, then modify the URL query parameters:

  • Set dtype_out_raster to png.
  • Set replace the values after /run/tiles with the /{z}/{x}/{y} template.
  • Set UDF parameters as needed.

For example:

https://www.fused.io/server/v1/realtime-shared/da71c7bf79376f2e88b37be9ecd2679f2e40a5b79f9b0f2c75e7ea9a3f0c5171/run/tiles/{z}/{x}/{y}?dtype_out_raster=png

Open the modal to create a new raster XYZ layer by right-clicking: XYZ Tiles -> New Connection. Now paste the UDF URL in the URI field and configure the layer as shown.

File

This should render the raster output tiles on the map. This example shows NDVI in the area surrounding Santa Rosa Island, off the coast of Southern California.

File

Note that the QGIS client is liable to timeout errors if it encounters a high number of concurrent requests and might show a warning similar to this one. Issues generally resolve after waiting some time.

2024-04-12T12:10:06     WARNING    Network request https://www.fused.io/server/v1/realtime-shared/da71c7bf79376f2e88b37be9ecd2679f2e40a5b79f9b0f2c75e7ea9a3f0c5171/run/tiles/14/2722/6554?dtype_out_raster=png timed out`

Vector File​

Load vector data onto the QGIS map.

As an example, the "Single Route" public UDF returns a composite vector line of driving directions between an origin and destination locations. Create a new instance of it on your workbench, generate a shared URL, and then modify the URL query parameters:

  • Set dtype_out_vector to geojson.
  • Set UDF parameters as needed.

For example:

https://www.fused.io/server/v1/realtime-shared/4f8fe6b81811ce011d7045b9fffbcfb43663637a4c626955821566fe62e6fb57/run/file?dtype_out_vector=csv&lat_start=37.7954425&lng_start=-122.3961885&lat_end=37.8592408&lng_end=-122.5349321

Open the modal to create a new vector layer by clicking: Layer -> New Layer -> Add Vector Layer. Now paste the UDF URL in the URI field and configure the layer as shown.

File

This should load the data and render it on the map.

File

Note that QGIS might cache the response of endpoint calls, which means UDF changes might not propagate immediately.