Allow applying dimensions through WMS FILTER parameter

README.rst

@@ -315,8 +315,42 @@ The additional value needed by the WMS is the URL of the server and the ``layers
 
 The previously defined ``mime_type`` is also used in the WMS requests.
 
-To customise the request you also have the attributes ``params``, ``headers``
+To customise the request you also have the attributes ``filter``, ``params``, ``headers``
 and ``generate_salt``.
+
+In ``filter`` you can specify a filter parameter for the layer. It behave like a template, populated with other params.
+This allow applying a WMS filter for dimension value.
+
+QGIS expression filter example:
+
+.. code-block:: yaml
+
+   layers:
+       layer_name:
+           type: wms
+           url: https://localhost/qgis_mapserv
+           layers: layer1,layer2
+           filter:  layer1:\"floor\" = '{floor}';
+                    layer2:\"floor\" = '{floor}'"
+
+OGC filter example:
+
+.. code-block:: yaml
+
+   layers:
+       layer_name:
+           type: wms
+           url: https://localhost/qgis_mapserv
+           layers: layer1,layer2
+           filter: "\
+   (<Filter>\
+   <PropertyIsEqualTo>\
+   <PropertyName>floor</PropertyName>\
+   <Literal>{FLOOR}</Literal>\
+   </PropertyIsEqualTo>\
+   </Filter>)\
+   ()"
+
 In ``params`` you can specify additional parameter of the WMS request,
 in ``headers`` you can modify the request headers. In ``version``, you can change the WMS version. See the
 `Proxy/cache issue`_ for additional informations.
@@ -531,9 +565,9 @@ Alternate mime type
 By default TileCloud support only the ``image/jpeg`` and ``image/png`` mime type.
 
 
-----------------
+---------------
 Amazon services
-----------------
+---------------
 
 Authentication
 --------------

tilecloud_chain/generate.py

@@ -385,6 +385,7 @@ def _get_tilestore_for_layer(self, layer):
                     border=layer['meta_buffer'] if layer.get('meta', False) else 0,
                     tilegrid=self._gene.get_grid(layer)['obj'],
                     params=params,
+                    filter=layer['filter']
                 ),),
                 headers=layer['headers'],
             )

tilecloud_chain/schema-layer-wms.yaml

@@ -9,6 +9,8 @@ mapping:
     layers:
         type: str
         required: true
+    filter:
+        type: str
     url:
         type: str
         required: true