Configuration Settings

The following configuration settings can be used to tweak server behavior.

The defaults are:

import math

# Flags
GISSERVER_CAPABILITIES_BOUNDING_BOX = True
GISSERVER_USE_DB_RENDERING = True
GISSERVER_SUPPORTED_CRS_ONLY = True
GISSERVER_COUNT_NUMBER_MATCHED = 1

# Output rendering
GISSERVER_FORCE_XY_OLD_CRS = True
GISSERVER_FORCE_XY_EPSG_4326 = True
GISSERVER_EXTRA_OUTPUT_FORMATS = {}
GISSERVER_GET_FEATURE_OUTPUT_FORMATS = {}

# Max page size
GISSERVER_DEFAULT_MAX_PAGE_SIZE = 5000
GISSERVER_GEOJSON_MAX_PAGE_SIZE = math.inf
GISSERVER_CSV_MAX_PAGE_SIZE = math.inf

# For debugging
GISSERVER_WRAP_FILTER_DB_ERRORS = True
GISSERVER_WFS_STRICT_STANDARD = False

GISSERVER_CAPABILITIES_BOUNDING_BOX

By default, the GetCapabilities response includes the bounding box of each feature. Since this is an expensive operation for large datasets, this can be disabled entirely.

If the project has the CACHES setting configured, the result will be briefly stored in a cache.

GISSERVER_USE_DB_RENDERING

By default, complex GML, GeoJSON and EWKT fragments are rendered by the database. This gives a better performance compared to GeoDjango, which needs to perform C-API calls indo GDAL for every coordinate of a geometry.

However, if you’re not using PostgreSQL+PostGIS, you may want to disable this optimization.

GISSERVER_SUPPORTED_CRS_ONLY

By default, clients may only request features in one of the supported coordinate reference systems that the FeatureType has listed. Often databases (such as PostGIS) and the GDAL backend support a lot more out of the box. By disabling this setting, all system-wide supported CRS values can be used in the ?SRSNAME=... parameter.

For performance reasons, the last 100 GDAL CoordTransform objects are stored in-memory. Allowing clients to change the output format so freely may cause some performance loss there.

GISSERVER_COUNT_NUMBER_MATCHED

By default, the whole page size is calculated. However, performing a COUNT is expensive in SQL. By disabling this, clients just simply need to fetch more pages. Possible values:

  • 0 = No counting.

  • 1 = Apply counting for all pages (the default).

  • 2 = Apply counting only for the first page.

In the WFS output, number_matched="unknown" will be found when paging is disabled.

GISSERVER_FORCE_XY_…

By default, WFS 2.0 follows the axis ordering of the CRS authority. This means urn:ogc:def:crs:EPSG::4326 will render in latitude/longitude ordering.

For maximum interoperability with legacy web-clients, this behavior is relaxed by returning legacy longitude/latitude (screen x/y) ordering when legacy notations are used.

  • Using GISSERVER_FORCE_XY_EPSG_4326=True will force EPSG:4326 into classic ordering.

  • Using GISSERVER_FORCE_XY_OLD_CRS=True will force http://www.opengis.net/gml/srs/epsg.xml#xxxx notations in classic ordering.

Clients that use the OGC recommended notations, like urn:ogc:def:crs:EPSG::4326 and http://www.opengis.net/def/crs/epsg/0/4326 always get the proper longitude/latitude.

This does not affect GeoJSON output. The GeoJSON standard mandates that data is always returned in urn:ogc:def:crs:OGC::CRS84 (which uses longitude/latitude ordering), to keep web-based clients simple.

GISSERVER_…_OUTPUT_FORMATS

The GISSERVER_*_OUTPUT_FORMATS settings make it easier to declare additional output formats. An example would be:

GISSERVER_EXTRA_OUTPUT_FORMATS = {
    "content-type": {
        "renderer_class": "dotted.path.to.CustomRenderer"
        "subtype": "type-alias",
        "title": "HTML title",
    },
}

See Extending the Server for a discussion on the required code.

GISSERVER_…_MAX_PAGE_SIZE

The GISSERVER_*_MAX_PAGE_SIZE settings allow to limit what the maximum requestable page size is. For GeoJSON and CSV, this is set to an infinite number which disables paging unless the ?COUNT=... request parameter is used.

Note

QGis often requests 1000 features per request, regardless of the maximum page size. Custom OutputRenderer subclasses may also override this setting.

GISSERVER_WFS_STRICT_STANDARD

By default, the server is configured to pass CITE conformance tests. Strictly speaking, the WFS server should return an exception when an invalid RESOURCEID format is offered that doens’t follow the “typename.identifier” notation.

GISSERVER_WRAP_FILTER_DB_ERRORS

By default, filter errors are nicely wrapped inside a WFS exception. This can be disabled for debugging purposes.