Added Chrome Support

Author: ujjawal-garg

README.md

@@ -36,6 +36,9 @@ The data can be any serial content (string, bit array, serialized
 JSON, etc), but be sure that your receiving application is able to
 parse and understand it. (e.g. `data = "Mary had a little lamb."`)
 
+gcm_key is the API key obtained from the Google Developer Console. 
+It is only needed if endpoint is https://android.googleapis.com/gcm/send
+
 `headers` is a `dict`ionary of additional HTTP header values (e.g.
 [VAPID](https://github.com/mozilla-services/vapid/tree/master/python)
 self identification headers). It is optional and may be omitted.
@@ -44,6 +47,11 @@ to send:
 ```
 WebPusher(subscription_info).send(data, headers)
 ```
+to send for Chrome:
+```
+WebPusher(subscription_info).send(data, gcm_key, headers)
+```
+
 You can also simply encode the data to send later by calling
 
 ```

pywebpush/__init__.py

@@ -4,7 +4,7 @@
 
 import base64
 import os
-
+import json
 import http_ece
 import pyelliptic
 import requests
@@ -151,10 +151,14 @@ def encode(self, data):
             'body': encrypted,
         })
 
-    def send(self, data, headers={}, ttl=0):
+    def send(self, data, gcm_key=None, reg_id=None, headers={}, ttl=0):
         """Encode and send the data to the Push Service.
 
         :param data: A serialized block of data (see encode() ).
+        :param gcm_key: API key obtained from the Google Developer Console. 
+            Needed if endpoint is https://android.googleapis.com/gcm/send
+        :param reg_id: registration id of the recipient. If not provided, 
+            it will be extracted from the endpoint.
         :param headers: A dictionary containing any additional HTTP headers.
         :param ttl: The Time To Live in seconds for this message if the
             recipient is not online. (Defaults to "0", which discards the
@@ -175,10 +179,32 @@ def send(self, data, headers={}, ttl=0):
             'encryption': "keyid=p256dh;salt=" +
             encoded['salt'].decode('utf8'),
         })
+
+        if self.subscription_info['endpoint'].startswith('https://android.googleapis.com/gcm/send'):
+
+            if not gcm_key:
+                raise WebPushException("API key not provided for google gcm endpoint")
+            endpoint = 'https://android.googleapis.com/gcm/send'
+            reg_ids = []
+            if not reg_id:
+                reg_id = self.subscription_info['endpoint'].rsplit('/', 1)[-1]
+            reg_ids.append(reg_id)
+            data = {}
+            data['registration_ids'] = reg_ids
+            data['raw_data'] = base64.b64encode(encoded.get('body'))
+            encoded_data = json.dumps(data)
+            headers.update({
+            'Authorization': 'key='+gcm_key,
+            'Content-Type': 'application/json',
+            })
+        else:
+            encoded_data = encoded.get('body')
+            endpoint = self.subscription_info['endpoint']
+
         if 'ttl' not in headers or ttl:
             headers['ttl'] = ttl
         # Additionally useful headers:
         # Authorization / Crypto-Key (VAPID headers)
-        return requests.post(self.subscription_info['endpoint'],
-                             data=encoded.get('body'),
+        return requests.post(endpoint,
+                             data=encoded_data,
                              headers=headers)