Added verbose comments, and added a scenarion to depict the client trying to subscribe on a restricted presence channel.

1 files changed, 52 insertions, 22 deletions

diff --git a/python/examples/pam_demo/demo.py b/python/examples/pam_demo/demo.py
index e00914d..a60730c 100644
--- a/python/examples/pam_demo/demo.py
+++ b/python/examples/pam_demo/demo.py
@@ -1,4 +1,3 @@
-
 from gevent.monkey import patch_all
 patch_all()
 
@@ -13,62 +12,93 @@ def get_unique(s):
 	return 'str-' + rand + '-' + s
 
 # public channel
+# This is the channel all clients announce themselves on -- or more generally speaking, a channel you expect the client
+# to "check-in" on to announce his state
+
 channel_public = get_unique("channel_public")
 
 # server auth key
+# Only the server has/knows about this auth token. It will be used to grant read on the "check-in" Presence channel
+
 server_auth_token = get_unique("server_auth_token")
 
-#client auth key
+# client auth key
+# only clients will use this authey -- it does not provide presence channel read access
+ 
 client_auth_token = get_unique("client_auth_token")
 
-#client uuid
+# each client must have a unique id -- a UUID, for presence information/state to bind to
+
+# client uuid
 client_uuid = get_unique("client_uuid")
 
-#server uuid
+# server uuid
 server_uuid = get_unique("server_uuid")
 
+# For the demo, we'll implement a SERVER called server, who is the authoritative 'admin' entity in the system
+# We'll also implement a CLIENT called client, who is an arbitrary hardware device member of the network
 
-#init server object
+# Please swap out the default 'pam' demo keys with your own PAM-enabled keys
+
+# init server object
 server = Pubnub(publish_key="pam", subscribe_key="pam", secret_key="pam", auth_key=server_auth_token, uuid=server_uuid)
 
-#init client object
+# init client object
 client = Pubnub(publish_key="pam", subscribe_key="pam", auth_key=client_auth_token, uuid=client_uuid)
 
+# To access a Presence channel with PAM, its format is CHANNELNAME-pnpres
+
 # Grant permission to server auth keys
+# grant r/w to public, and r/w public Presence (public-pnpres)
+
 print(server.grant(channel=channel_public, auth_key=server_auth_token, read=True, write=True))
 print(server.grant(channel=channel_public + '-pnpres', auth_key=server_auth_token, read=True, write=True))
 
 # Grant permission to client auth keys
+# grant r/w to public, and w-only access to public Presence (public-pnpres)
 print(server.grant(channel=channel_public, auth_key=client_auth_token, read=True, write=False))
-print(server.grant(channel=channel_public + '-pnpres', auth_key=client_auth_token, read=True, write=False))
+print(server.grant(channel=channel_public + '-pnpres', auth_key=client_auth_token, read=False, write=False))
 
+# Now, we'll run it to watch it work as advertised...
 
+# Define some simple callabcks for the Server and Client
 
-def _server_callback(message, channel):
-	print(message)
+def _server_message_callback(message, channel):
+	print("Server heard: " + message)
+
+def _client_callback(channel, message):
+    print("Client heard: " + message)
 
 def _error_callback(error):
-	print(error)
+	print("Error: " + error)
 
-#server subscribes to public channel
-server.subscribe(channels=channel_public, callback=_server_callback, error=_error_callback)
+def _server_presence_callback(message, channel):
+    print message
+    if 'action' in message:
+        if message['action'] == 'join' and message['uuid'] == client_uuid:
+            print "Server can see that client with UUID " + message['uuid'] + " has a state of " + json.dumps(message['data'])
 
+def _client_presence_callback(message, channel):
+    print message
+    if 'action' in message:
+        if message['action'] == 'join' and message['uuid'] == client_uuid:
+            print "Client can see that client with UUID " + message['uuid'] + " has a state of " + json.dumps(message['data'])
 
+# server subscribes to public channel
+server.subscribe(channels=channel_public, callback=_server_message_callback, error=_error_callback)
 
-def _server_presence_callback(message, channel):
-	print message
-	if 'action' in message:
-		if message['action'] == 'join' and message['uuid'] == client_uuid:
-			print "Only I can see that client with UUID " + message['uuid'] + " has a state of " + json.dumps(message['data'])
+# server subscribes to presence events on public channel
+# presence() is a convienence method that subscribes to channel-pnpres with special logic for handling
+# presence-event formatted messages
 
-# server subscribes to presence events on public channel 
+## uncomment out to see server able to read on presence channel
 server.presence(channel=channel_public, callback=_server_presence_callback, error=_error_callback)
 
+# now if the client tried to subscribe on the presence channel, and therefore, get state info
+# he is explicitly denied!
 
-
-
-def _client_callback(channel, message):
-	print(message)
+## uncomment out to see client not able to read on presence channel
+#client.presence(channel=channel_public, callback=_client_presence_callback, error=_error_callback)
 
 # client subscribes to public channel
 client.subscribe(channels=channel_public, state={ "myKey" : get_unique("foo")}, callback=_client_callback, error=_error_callback)