[OAPIF] faster way to get feature count (backport of #51590)

qgis · Oct 3, 2023 · a8da6b6 · a8da6b6
1 parent 941477b
commit a8da6b6
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Showing 3 changed files with 36 additions and 3 deletions.
diff --git a/src/providers/wfs/oapif/qgsoapifprovider.cpp b/src/providers/wfs/oapif/qgsoapifprovider.cpp
@@ -269,6 +269,34 @@ QgsWkbTypes::Type QgsOapifProvider::wkbType() const
 
 long long QgsOapifProvider::featureCount() const
 {
+  // If no filter is set try the fast way of retrieving the feature count
+  if ( mSubsetString.isEmpty() )
+  {
+    QString url = mShared->mItemsUrl;
+    url += QLatin1String( "?limit=1" );
+    url = mShared->appendExtraQueryParameters( url );
+
+    if ( !mShared->mServerFilter.isEmpty() )
+    {
+      url += QLatin1Char( '&' );
+      url += mShared->mServerFilter;
+    }
+
+    QgsOapifItemsRequest itemsRequest( mShared->mURI.uri(), url );
+    if ( !itemsRequest.request( true, false ) )
+      return -1;
+    if ( itemsRequest.errorCode() != QgsBaseNetworkRequest::NoError )
+      return -1;
+
+    const long long featureCount = itemsRequest.numberMatched();
+    if ( featureCount >= 0 )
+    {
+      mShared->setFeatureCount( featureCount, true );
+      return featureCount;
+    }
+  }
+
+  // Retry the slow way by active filter or numberMatched parameter not sent from server
   if ( mUpdateFeatureCountAtNextFeatureCountRequest )
   {
     mUpdateFeatureCountAtNextFeatureCountRequest = false;

diff --git a/src/providers/wfs/oapif/qgsoapifprovider.h b/src/providers/wfs/oapif/qgsoapifprovider.h
@@ -109,8 +109,8 @@ class QgsOapifProvider final: public QgsVectorDataProvider
     //! Layer metadata
     QgsLayerMetadata mLayerMetadata;
 
-    //! Set to true by setSubsetString() if updateFeatureCount is true
-    mutable bool mUpdateFeatureCountAtNextFeatureCountRequest = false;
+    //! Set to true by reloadProviderData()
+    mutable bool mUpdateFeatureCountAtNextFeatureCountRequest = true;
 
     //! Initial requests
     bool init();
@@ -212,7 +212,7 @@ class QgsOapifSharedData final: public QObject, public QgsBackgroundCachedShared
 
     bool hasServerSideFilter() const override { return false; }
 
-    bool supportsFastFeatureCount() const override { return false; }
+    bool supportsFastFeatureCount() const override { return mURI.filter().isEmpty(); }
 
     QgsRectangle getExtentFromSingleFeatureRequest() const override { return QgsRectangle(); }
 

diff --git a/tests/src/python/test_provider_oapif.py b/tests/src/python/test_provider_oapif.py
@@ -162,6 +162,7 @@ def setUpClass(cls):
 
         items = {
             "type": "FeatureCollection",
+            "numberMatched": 5,
             "features": [
                 {"type": "Feature", "id": "feat.1",
                  "properties": {"pk": 1, "cnt": 100, "name": "Orange", "name2": "oranGe", "num_char": "1", "dt": "2020-05-03 12:13:14", "date": "2020-05-03", "time": "12:13:14"},
@@ -181,6 +182,10 @@ def setUpClass(cls):
             ]
         }
 
+        # limit 1 for getting count
+        with open(sanitize(endpoint, '/collections/mycollection/items?limit=1&' + ACCEPT_ITEMS), 'wb') as f:
+            f.write(json.dumps(items).encode('UTF-8'))
+
         # first items
         with open(sanitize(endpoint, '/collections/mycollection/items?limit=10&' + ACCEPT_ITEMS), 'wb') as f:
             f.write(json.dumps(items).encode('UTF-8'))