Firestore watch samples (GoogleCloudPlatform#1883)

frankyn · kurtisvg · commit a64e4aff958f · 2018-12-18T17:12:40.000-08:00
* Add base code for realtime listener snippets
* Updating samples based on fixes
* Update requires to point to latest release
diff --git a/firestore/cloud-client/requirements.txt b/firestore/cloud-client/requirements.txt
@@ -1 +1 @@
-google-cloud-firestore==0.30.0
+google-cloud-firestore==0.31.0
diff --git a/firestore/cloud-client/snippets.py b/firestore/cloud-client/snippets.py
@@ -12,6 +12,7 @@
 # limitations under the License.
 
 import datetime
+from time import sleep
 
 from google.cloud import firestore
 import google.cloud.exceptions
@@ -603,6 +604,114 @@ def cursor_paginate():
     return next_query
 
 
+def listen_document():
+    db = firestore.Client()
+    # [START listen_document]
+
+    # Create a callback on_snapshot function to capture changes
+    def on_snapshot(doc_snapshot, changes, read_time):
+        for doc in doc_snapshot:
+            print(u'Received document snapshot: {}'.format(doc.id))
+
+    doc_ref = db.collection(u'cities').document(u'SF')
+
+    # Watch the document
+    doc_watch = doc_ref.on_snapshot(on_snapshot)
+    # [END listen_document]
+
+    # Creating document
+    data = {
+        u'name': u'San Francisco',
+        u'state': u'CA',
+        u'country': u'USA',
+        u'capital': False,
+        u'population': 860000
+    }
+    doc_ref.set(data)
+    sleep(3)
+    # [START detach_listener]
+    # Terminate watch on a document
+    doc_watch.unsubscribe()
+    # [START detach_listener]
+
+
+def listen_multiple():
+    db = firestore.Client()
+    # [START listen_multiple]
+
+    # Create a callback on_snapshot function to capture changes
+    def on_snapshot(col_snapshot, changes, read_time):
+        print(u'Callback received query snapshot.')
+        print(u'Current cities in California:')
+        for doc in col_snapshot:
+            print(u'{}'.format(doc.id))
+
+    col_query = db.collection(u'cities').where(u'state', u'==', u'CA')
+
+    # Watch the collection query
+    query_watch = col_query.on_snapshot(on_snapshot)
+
+    # [END listen_multiple]
+    # Creating document
+    data = {
+        u'name': u'San Francisco',
+        u'state': u'CA',
+        u'country': u'USA',
+        u'capital': False,
+        u'population': 860000
+    }
+    db.collection(u'cities').document(u'SF').set(data)
+    sleep(1)
+    query_watch.unsubscribe()
+
+
+def listen_for_changes():
+    db = firestore.Client()
+    # [START listen_for_changes]
+
+    # Create a callback on_snapshot function to capture changes
+    def on_snapshot(col_snapshot, changes, read_time):
+        print(u'Callback received query snapshot.')
+        print(u'Current cities in California: ')
+        for change in changes:
+            if change.type.name == "ADDED":
+                print(u'New city: {}'.format(change.document.id))
+            elif change.type.name == "MODIFIED":
+                print(u'Modified city: {}'.format(change.document.id))
+            elif change.type.name == "REMOVED":
+                print(u'Removed city: {}'.format(change.document.id))
+
+    col_query = db.collection(u'cities').where(u'state', u'==', u'CA')
+
+    # Watch the collection query
+    query_watch = col_query.on_snapshot(on_snapshot)
+
+    # [END listen_for_changes]
+    mtv_document = db.collection(u'cities').document(u'MTV')
+    # Creating document
+    mtv_document.set({
+        u'name': u'Mountain View',
+        u'state': u'CA',
+        u'country': u'USA',
+        u'capital': False,
+        u'population': 80000
+    })
+
+    # Modifying document
+    mtv_document.update({
+        u'name': u'Mountain View',
+        u'state': u'CA',
+        u'country': u'USA',
+        u'capital': False,
+        u'population': 90000
+    })
+
+    # Delete document
+    mtv_document.delete()
+    sleep(1)
+    query_watch.unsubscribe()
+
+
 def cursor_multiple_conditions():
     db = firestore.Client()
     # [START cursor_multiple_conditions]
diff --git a/firestore/cloud-client/snippets_test.py b/firestore/cloud-client/snippets_test.py
@@ -220,5 +220,26 @@ def test_delete_field(db):
     snippets.delete_field()
 
 
+def test_listen_document(capsys):
+    snippets.listen_document()
+    out, _ = capsys.readouterr()
+    assert "Received document snapshot: SF" in out
+
+
+def test_listen_multiple(capsys):
+    snippets.listen_multiple()
+    out, _ = capsys.readouterr()
+    assert "Current cities in California:" in out
+    assert "SF" in out
+
+
+def test_listen_for_changes(capsys):
+    snippets.listen_for_changes()
+    out, _ = capsys.readouterr()
+    assert "New city: MTV" in out
+    assert "Modified city: MTV" in out
+    assert "Removed city: MTV" in out
+
+
 def test_delete_full_collection():
     snippets.delete_full_collection()

Original file line number	Diff line number	Diff line change
`@@ -1 +1 @@`
`1`		`-google-cloud-firestore==0.30.0`
	`1`	`+google-cloud-firestore==0.31.0`