Add count query snippets

Author: morganchen12

firestore/main/index.js

@@ -947,6 +947,25 @@ async function deleteQueryBatch(db, query, resolve) {
 
 // [END firestore_data_delete_collection]
 
+async function countAggregateCollection(db) {
+  // [START count_aggregation_collection]
+  const collectionRef = db.collection('cities');
+  const snapshot = await collectionRef.count().get();
+
+  console.log(snapshot.data.count);
+  // [END count_aggregation_collection]
+}
+
+async function countAggregateQuery(db) {
+  // [START count_aggregation_query]
+  const collectionRef = db.collection('cities');
+  const query = collectionRef.where('state', '==', 'CA');
+  const snapshot = await collectionRef.count().get();
+
+  console.log(snapshot.data.count);
+  // [END count_aggregation_query]
+}
+
 // ============================================================================
 // MAIN
 // ============================================================================