CQL support


As of now the available providers supported for CQL filtering are limited to Elasticsearch and PostgreSQL.


Support of CQL is limited to Simple CQL filter and thus it allows to query with the following predicates:

  • comparison predicates

  • spatial predicates

  • temporal predicates


At the moment Elasticsearch supports only the CQL dialect with the JSON encoding CQL-JSON.

PostgreSQL supports both CQL-JSON and CQL-text dialects, CQL-JSON and CQL-TEXT


The PostgreSQL provider uses pygeofilter allowing a range of filter expressions, see examples for:

Using Elasticsearch the following type of queries are supported right now:

  • between predicate query

  • Logical and query with between and eq expression

  • Spatial query with bbox

Note that when using a spatial operator in your filter expression, geometries are by default interpreted as being in the OGC:CRS84 Coordinate Reference System. If you wish to provide geometries in other CRS, use the filter-crs query parameter with a suitable value.

Alternatively, a geometry’s CRS may also be included using Extended Well-Known Text, in which case it will override the value of filter-crs (if any) - this can be useful if your filtering expression is complex enough to need multiple geometries expressed in different CRSs. The standard way of providing filter-crs as an additional query parameter is preferable for most cases.


A BETWEEN example for a specific property through an HTTP POST request:

curl --location --request POST 'http://localhost:5000/collections/nhsl_hazard_threat_all_indicators_s_bc/items?f=json&limit=50&filter-lang=cql-json' \
--header 'Content-Type: application/query-cql-json' \
--data-raw '{
  "between": {
    "value": { "property": "properties.MHn_Intensity" },
    "lower": 0.59,
    "upper": 0.60


curl --location --request POST 'http://localhost:5000/collections/recentearthquakes/items?f=json&limit=10&filter-lang=cql-json'
--header 'Content-Type: application/query-cql-json'
--data-raw '{
    "value":{"property": "ml"},

The same BETWEEN query using HTTP GET request formatted as CQL text and URL encoded as below:

curl "http://localhost:5000/collections/recentearthquakes/items?f=json&limit=10&filter=ml%20BETWEEN%204%20AND%204.5"

An EQUALS example for a specific property:

curl --location --request POST 'http://localhost:5000/collections/recentearthquakes/items?f=json&limit=10&filter-lang=cql-json'
--header 'Content-Type: application/query-cql-json'
--data-raw '{
    "eq":[{"property": "user_entered"},"APBE"]

A CROSSES example via an HTTP GET request. The CQL text is passed via the filter parameter.

curl "http://localhost:5000/collections/hot_osm_waterways/items?f=json&filter=CROSSES(foo_geom,%20LINESTRING(28%20-2,%2030%20-4))"

A DWITHIN example via HTTP GET and using a custom CRS for the filter geometry:

curl "http://localhost:5000/collections/beni/items?filter=DWITHIN(geometry,POINT(1392921%205145517),100,meters)&filter-crs=http://www.opengis.net/def/crs/EPSG/0/3857"

The same example, but this time providing a geometry in EWKT format:

curl "http://localhost:5000/collections/beni/items?filter=DWITHIN(geometry,SRID=3857;POINT(1392921%205145517),100,meters)"

Note that the CQL text has been URL encoded. This is required in curl commands but when entering in a browser, plain text can be used e.g. CROSSES(foo_geom, LINESTRING(28 -2, 30 -4)).