Using Python 3 compatible print statements in snippets (#157) (#159)

* Uses python 3 compatible print statements.

* Fixed Python 3 incompatible print syntax used in snippets.

* adjusting snippets to lint happily on Python <3

 - added "from __future__ import print_function" in snippets using
   print to make pylint "print-function-aware" and lint Python 3.x
   print-syntax without errors when running under Python 2.x.

* remove unwanted parens from print statements in snippets

 - delete duplicate parens added in previous commits

* Uses python 3 compatible print statements.

* Fixed Python 3 incompatible print syntax used in snippets.

 - added "from __future__ import print_function" in snippets using
   print to make pylint "print-function-aware" and lint Python 3.x
   print-syntax without errors when running under Python 2.x.
 - delete duplicate parens used in print statements

Author: Nicolas Couture

snippets/auth/get_service_account_tokens.py

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 # [START get_service_account_tokens]
 from firebase_admin import credentials
 
@@ -24,4 +26,4 @@
 # After expiration_time, you must generate a new access token
 # [END get_service_account_tokens]
 
-print 'The access token {} expires at {}'.format(access_token, expiration_time)
+print('The access token {} expires at {}'.format(access_token, expiration_time))

snippets/auth/index.py

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 import datetime
 import sys
 import time
@@ -55,7 +57,7 @@ def access_services_default():
 
     # Initialize the default app
     default_app = firebase_admin.initialize_app(cred)
-    print default_app.name  # "[DEFAULT]"
+    print(default_app.name)  # "[DEFAULT]"
 
     # Retrieve services via the auth package...
     # auth.create_custom_token(...)
@@ -73,8 +75,8 @@ def access_services_nondefault():
     #  Initialize another app with a different config
     other_app = firebase_admin.initialize_app(cred, name='other')
 
-    print default_app.name    # "[DEFAULT]"
-    print other_app.name      # "other"
+    print(default_app.name)    # "[DEFAULT]"
+    print(other_app.name)      # "other"
 
     # Retrieve default services via the auth package...
     # auth.create_custom_token(...)
@@ -119,7 +121,7 @@ def verify_token_uid(id_token):
     decoded_token = auth.verify_id_token(id_token)
     uid = decoded_token['uid']
     # [END verify_token_uid]
-    print uid
+    print(uid)
     firebase_admin.delete_app(default_app)
 
 def verify_token_uid_check_revoke(id_token):
@@ -152,21 +154,21 @@ def revoke_refresh_token_uid():
     user = auth.get_user(uid)
     # Convert to seconds as the auth_time in the token claims is in seconds.
     revocation_second = user.tokens_valid_after_timestamp / 1000
-    print 'Tokens revoked at: {0}'.format(revocation_second)
+    print('Tokens revoked at: {0}'.format(revocation_second))
     # [END revoke_tokens]
     # [START save_revocation_in_db]
     metadata_ref = firebase_admin.db.reference("metadata/" + uid)
     metadata_ref.set({'revokeTime': revocation_second})
     # [END save_revocation_in_db]
-    print uid
+    print(uid)
     firebase_admin.delete_app(default_app)
 
 def get_user(uid):
     # [START get_user]
     from firebase_admin import auth
 
     user = auth.get_user(uid)
-    print 'Successfully fetched user data: {0}'.format(user.uid)
+    print('Successfully fetched user data: {0}'.format(user.uid))
     # [END get_user]
 
 def get_user_by_email():
@@ -175,7 +177,7 @@ def get_user_by_email():
     from firebase_admin import auth
 
     user = auth.get_user_by_email(email)
-    print 'Successfully fetched user data: {0}'.format(user.uid)
+    print('Successfully fetched user data: {0}'.format(user.uid))
     # [END get_user_by_email]
 
 def get_user_by_phone_number():
@@ -184,7 +186,7 @@ def get_user_by_phone_number():
     from firebase_admin import auth
 
     user = auth.get_user_by_phone_number(phone)
-    print 'Successfully fetched user data: {0}'.format(user.uid)
+    print('Successfully fetched user data: {0}'.format(user.uid))
     # [END get_user_by_phone]
 
 def create_user():
@@ -197,15 +199,15 @@ def create_user():
         display_name='John Doe',
         photo_url='http://www.example.com/12345678/photo.png',
         disabled=False)
-    print 'Sucessfully created new user: {0}'.format(user.uid)
+    print('Sucessfully created new user: {0}'.format(user.uid))
     # [END create_user]
     return user.uid
 
 def create_user_with_id():
     # [START create_user_with_id]
     user = auth.create_user(
         uid='some-uid', email='user@example.com', phone_number='+15555550100')
-    print 'Sucessfully created new user: {0}'.format(user.uid)
+    print('Sucessfully created new user: {0}'.format(user.uid))
     # [END create_user_with_id]
 
 def update_user(uid):
@@ -219,13 +221,13 @@ def update_user(uid):
         display_name='John Doe',
         photo_url='http://www.example.com/12345678/photo.png',
         disabled=True)
-    print 'Sucessfully updated user: {0}'.format(user.uid)
+    print('Sucessfully updated user: {0}'.format(user.uid))
     # [END update_user]
 
 def delete_user(uid):
     # [START delete_user]
     auth.delete_user(uid)
-    print 'Successfully deleted user'
+    print('Successfully deleted user')
     # [END delete_user]
 
 def set_custom_user_claims(uid):
@@ -249,7 +251,7 @@ def set_custom_user_claims(uid):
     # Lookup the user associated with the specified uid.
     user = auth.get_user(uid)
     # The claims can be accessed on the user record.
-    print user.custom_claims.get('admin')
+    print(user.custom_claims.get('admin'))
     # [END read_custom_user_claims]
 
 def set_custom_user_claims_script():
@@ -282,14 +284,14 @@ def list_all_users():
     page = auth.list_users()
     while page:
         for user in page.users:
-            print 'User: ' + user.uid
+            print('User: ' + user.uid)
         # Get next batch of users.
         page = page.get_next_page()
 
     # Iterate through all users. This will still retrieve users in batches,
     # buffering no more than 1000 users in memory at a time.
     for user in auth.list_users().iterate_all():
-        print 'User: ' + user.uid
+        print('User: ' + user.uid)
     # [END list_all_users]
 
 def create_session_cookie(flask, app):
@@ -340,7 +342,7 @@ def check_auth_time(id_token, flask):
 
 def verfy_session_cookie(app, flask):
     def serve_content_for_user(decoded_claims):
-        print 'Serving content with claims:', decoded_claims
+        print('Serving content with claims:', decoded_claims)
         return flask.jsonify({'status': 'success'})
 
     # [START session_verify]
@@ -362,7 +364,7 @@ def access_restricted_content():
 
 def check_permissions(session_cookie, flask):
     def serve_content_for_admin(decoded_claims):
-        print 'Serving content with claims:', decoded_claims
+        print('Serving content with claims:', decoded_claims)
         return flask.jsonify({'status': 'success'})
 
     # [START session_verify_with_permission_check]

snippets/database/index.py

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 import firebase_admin
 from firebase_admin import credentials
 from firebase_admin import db
@@ -32,7 +34,7 @@ def authenticate_with_admin_privileges():
 
     # As an admin, the app has access to read and write all data, regradless of Security Rules
     ref = db.reference('restricted_access/secret_document')
-    print ref.get()
+    print(ref.get())
     # [END authenticate_with_admin_privileges]
     firebase_admin.delete_app(firebase_admin.get_app())
 
@@ -55,7 +57,7 @@ def authenticate_with_limited_privileges():
 
     # The app only has access as defined in the Security Rules
     ref = db.reference('/some_resource')
-    print ref.get()
+    print(ref.get())
     # [END authenticate_with_limited_privileges]
     firebase_admin.delete_app(firebase_admin.get_app())
 
@@ -76,7 +78,7 @@ def authenticate_with_guest_privileges():
 
     # The app only has access to public data as defined in the Security Rules
     ref = db.reference('/public_resource')
-    print ref.get()
+    print(ref.get())
     # [END authenticate_with_guest_privileges]
     firebase_admin.delete_app(firebase_admin.get_app())
 
@@ -88,7 +90,7 @@ def get_reference():
     # Get a database reference to our blog.
     ref = db.reference('server/saving-data/fireblog')
     # [END get_reference]
-    print ref.key
+    print(ref.key)
 
 def set_value():
     ref = db.reference('server/saving-data/fireblog')
@@ -201,7 +203,7 @@ def get_push_key():
     # Get the unique key generated by push()
     post_id = new_post_ref.key
     # [END push_key]
-    print post_id
+    print(post_id)
 
 def run_transaction():
     # [START transaction]
@@ -211,9 +213,9 @@ def increment_votes(current_value):
     upvotes_ref = db.reference('server/saving-data/fireblog/posts/-JRHTHaIs-jNPLXOQivY/upvotes')
     try:
         new_vote_count = upvotes_ref.transaction(increment_votes)
-        print 'Transaction completed'
+        print('Transaction completed')
     except db.TransactionError:
-        print 'Transaction failed to commit'
+        print('Transaction failed to commit')
     # [END transaction]
 
 def read_value():
@@ -225,89 +227,89 @@ def read_value():
     ref = db.reference('server/saving-data/fireblog/posts')
 
     # Read the data at the posts reference (this is a blocking operation)
-    print ref.get()
+    print(ref.get())
     # [END read_value]
 
 def order_by_child():
     # [START order_by_child]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_child('height').get()
     for key, val in snapshot.items():
-        print '{0} was {1} meters tall'.format(key, val)
+        print('{0} was {1} meters tall'.format(key, val))
     # [END order_by_child]
 
 def order_by_nested_child():
     # [START order_by_nested_child]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_child('dimensions/height').get()
     for key, val in snapshot.items():
-        print '{0} was {1} meters tall'.format(key, val)
+        print('{0} was {1} meters tall'.format(key, val))
     # [END order_by_nested_child]
 
 def order_by_key():
     # [START order_by_key]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_key().get()
-    print snapshot
+    print(snapshot)
     # [END order_by_key]
 
 def order_by_value():
     # [START order_by_value]
     ref = db.reference('scores')
     snapshot = ref.order_by_value().get()
     for key, val in snapshot.items():
-        print 'The {0} dinosaur\'s score is {1}'.format(key, val)
+        print('The {0} dinosaur\'s score is {1}'.format(key, val))
     # [END order_by_value]
 
 def limit_query():
     # [START limit_query_1]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_child('weight').limit_to_last(2).get()
     for key in snapshot:
-        print key
+        print(key)
     # [END limit_query_1]
 
     # [START limit_query_2]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_child('height').limit_to_first(2).get()
     for key in snapshot:
-        print key
+        print(key)
     # [END limit_query_2]
 
     # [START limit_query_3]
     scores_ref = db.reference('scores')
     snapshot = scores_ref.order_by_value().limit_to_last(3).get()
     for key, val in snapshot.items():
-        print 'The {0} dinosaur\'s score is {1}'.format(key, val)
+        print('The {0} dinosaur\'s score is {1}'.format(key, val))
     # [END limit_query_3]
 
 def range_query():
     # [START range_query_1]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_child('height').start_at(3).get()
     for key in snapshot:
-        print key
+        print(key)
     # [END range_query_1]
 
     # [START range_query_2]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_key().end_at('pterodactyl').get()
     for key in snapshot:
-        print key
+        print(key)
     # [END range_query_2]
 
     # [START range_query_3]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_key().start_at('b').end_at(u'b\uf8ff').get()
     for key in snapshot:
-        print key
+        print(key)
     # [END range_query_3]
 
     # [START range_query_4]
     ref = db.reference('dinosaurs')
     snapshot = ref.order_by_child('height').equal_to(25).get()
     for key in snapshot:
-        print key
+        print(key)
     # [END range_query_4]
 
 def complex_query():
@@ -320,10 +322,10 @@ def complex_query():
         # Data is ordered by increasing height, so we want the first entry.
         # Second entry is stegosarus.
         for key in snapshot:
-            print 'The dinosaur just shorter than the stegosaurus is {0}'.format(key)
+            print('The dinosaur just shorter than the stegosaurus is {0}'.format(key))
             return
     else:
-        print 'The stegosaurus is the shortest dino'
+        print('The stegosaurus is the shortest dino')
     # [END complex_query]
 
 

snippets/messaging/cloud_messaging.py

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 import datetime
 
 from firebase_admin import messaging