Merge branch 'develop'
diff --git a/docs/source/conf.py b/docs/source/conf.py
index 40647a0..8007edf 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -54,7 +54,7 @@
 # The short X.Y version.
 version = '0.8'
 # The full version, including alpha/beta/rc tags.
-release = '0.8.0'
+release = '0.8.2'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
diff --git a/docs/source/predictionio.rst b/docs/source/predictionio.rst
index e7b90e7..a31f155 100644
--- a/docs/source/predictionio.rst
+++ b/docs/source/predictionio.rst
@@ -10,7 +10,7 @@
    and extract prediction results.
 
 Please read `PredictionIO Quick Start
-<http://docs.prediction.io/0.8.0/tutorials/engines/quickstart.html>`_ for
+<http://docs.prediction.io/0.8.2/recommendation/quickstart.html>`_ for
 detailed explanation.
 
 predictionio.EventClient Class
@@ -104,7 +104,7 @@
 For example, to import 100000 of user records::
 
   >>> # generate 100000 asynchronous requests and store the AsyncRequest objects
-  >>> event_client = EventClient(app_id=1)
+  >>> event_client = EventClient(access_key=<YOUR_ACCESS_KEY>)
   >>> for i in range(100000):
   >>>   event_client.aset_user(user_record[i].uid)
   >>>
diff --git a/examples/demo-movielens/README.md b/examples/demo-movielens/README.md
index 4f7f47e..b555417 100644
--- a/examples/demo-movielens/README.md
+++ b/examples/demo-movielens/README.md
@@ -5,12 +5,12 @@
 
 Step 1. Get sample data and unzip it.
 ```
-$ curl -o ml-100k.zip http://www.grouplens.org/system/files/ml-100k.zip
+$ curl -o ml-100k.zip http://files.grouplens.org/datasets/movielens/ml-100k.zip
 $ unzip ml-100k.zip
 ```
 
 Step 2. Run this app:
 ```
-$ python -m examples.demo-movielens.batch_import <app_id> <server_url>
+$ python -m examples.demo-movielens.batch_import <access_key> <server_url>
 ```
 
diff --git a/examples/demo-movielens/batch_import.py b/examples/demo-movielens/batch_import.py
index fa2e1c0..762a1f3 100644
--- a/examples/demo-movielens/batch_import.py
+++ b/examples/demo-movielens/batch_import.py
@@ -3,11 +3,27 @@
 import predictionio
 import sys
 import pytz
+import datetime
 
-def batch_import_task(app_id, app_data, client, all_info=False):
+def batch_import_task(app_data, client, all_info=False):
+  # event_time is an important properties used by the PredictionIO platform. It
+  # is particularly useful in generating training and testing set, which uses
+  # event_time for splitting. Hence, when we import data, better to make the
+  # event_time as approximate to fact as possible.
+  #
+  # However, in many cases, the data doesn't come with a time. Movie-lens' user
+  # data, for example, only reveals the age, gender, occupation, and zip code of
+  # a user. It doesn't report when the user is "created". Likewise, for items,
+  # it only reports the release date.
+  #
+  # To remedy this problem, we have to make some assumptions to the data. In
+  # this import script, the event_time for user is set to epoch=0, and the
+  # event_time for item is set to the release_date + 00:00:00 UTC.
 
   print "[Info] Importing users to PredictionIO..."
+  user_create_time = datetime.datetime.fromtimestamp(0, tz=pytz.utc)
   count = 0
+  set_user_request_list = []
   for k, v in app_data.get_users().iteritems():
     count += 1
     if all_info:
@@ -17,13 +33,20 @@
         sys.stdout.write('\r[Info] %s' % count)
         sys.stdout.flush()
 
-    client.aset_user(uid=v.uid)
+    set_user_request_list.append(
+        client.aset_user(uid=v.uid, event_time=user_create_time))
 
+  [r.get_response() for r in set_user_request_list]
   sys.stdout.write('\r[Info] %s users were imported.\n' % count)
   sys.stdout.flush()
 
   print "[Info] Importing items to PredictionIO..."
   count = 0
+  set_item_request_list = []
+  # event_time is a datetime, hence need to add a time component to the release
+  # date.
+  midnight_utc = datetime.time(0, 0, 0, tzinfo=pytz.utc)
+  epoch = datetime.datetime.fromtimestamp(0, tz=pytz.utc)
   for k, v in app_data.get_items().iteritems():
     count += 1
     if all_info:
@@ -34,18 +57,34 @@
         sys.stdout.flush()
 
     itypes = ("movie",) + v.genres
-    client.aset_item(iid=v.iid,
-      properties={ 
-        "pio_itypes" : list(itypes),
-        "pio_starttime" : v.release_date.isoformat() + 'Z',
-        "name" : v.name,
-        "year" : v.year } )
 
+    release_datetime = datetime.datetime.combine(
+        v.release_date,
+        midnight_utc)
+
+    # event_time must be after epoch.
+    event_time = release_datetime if release_datetime > epoch else epoch
+
+    utf8_name = v.name.decode('utf-8', 'ignore')
+    
+    set_item_request = client.aset_item(
+        iid=v.iid,
+        event_time=event_time,
+        properties={ 
+          "pio_itypes": list(itypes),
+          "pio_starttime": release_datetime.isoformat(),
+          "name": utf8_name,
+          "year": v.year } )
+
+    set_item_request_list.append(set_item_request)
+
+  [r.get_response() for r in set_item_request_list]
   sys.stdout.write('\r[Info] %s items were imported.\n' % count)
   sys.stdout.flush()
 
   print "[Info] Importing rate actions to PredictionIO..."
   count = 0
+  create_event_request_list = []
   for v in app_data.get_rate_actions():
     count += 1
     if all_info:
@@ -66,6 +105,9 @@
         event_time=v.t.replace(tzinfo=pytz.utc),
         )
 
+    create_event_request_list.append(req)
+
+  [r.get_response() for r in create_event_request_list]
   sys.stdout.write('\r[Info] %s rate actions were imported.\n' % count)
   sys.stdout.flush()
 
@@ -73,12 +115,12 @@
 if __name__ == '__main__':
   if len(sys.argv) < 3:
     sys.exit("Usage: python -m examples.demo-movielens.batch_import "
-        "<app_id> <url>")
+        "<access_key> <url>")
 
-  app_id = int(sys.argv[1])
+  access_key = sys.argv[1]
 
   client = predictionio.EventClient(
-      app_id=app_id,
+      access_key=access_key,
       url=sys.argv[2],
       threads=5,
       qsize=500)
@@ -87,5 +129,5 @@
   print "Status:", client.get_status()
   
   app_data = AppData()
-  batch_import_task(app_id, app_data, client)
+  batch_import_task(app_data, client)
   client.close()
diff --git a/examples/event_sample.py b/examples/event_sample.py
index e2a1411..0a7a339 100644
--- a/examples/event_sample.py
+++ b/examples/event_sample.py
@@ -4,7 +4,10 @@
 import pytz
 import sys
 
-client = EventClient(app_id=4, url="http://localhost:7070")
+access_key = None
+assert access_key is not None, "Please create an access key with 'pio app new'"
+
+client = EventClient(access_key=access_key, url="http://localhost:7070")
 
 # Check status
 print("Check status")
diff --git a/examples/import_yahoo.py b/examples/import_yahoo.py
index 69421d4..93b367d 100644
--- a/examples/import_yahoo.py
+++ b/examples/import_yahoo.py
@@ -2,13 +2,14 @@
 Import historical stock data from yahoo finance.
 """
 
-import argparse
 from datetime import datetime
+from pandas.io import data as pdata
+import argparse
+import numpy
 import predictionio
 import pytz
+import sys
 import time
-from pandas.io import data as pdata
-import numpy
 
 EPOCH = datetime(1970, 1, 1, tzinfo=pytz.utc)
 
@@ -70,7 +71,7 @@
   return (dt - EPOCH).total_seconds()
 
 
-def import_data(client, app_id, ticker, start_time, end_time, event_time):
+def import_data(client, access_key, ticker, start_time, end_time, event_time):
   print "Importing:", ticker, start_time, end_time
 
   try:
@@ -114,7 +115,7 @@
   print(response)
 
 
-def import_all(app_id):
+def import_all(access_key):
   """This method import all SP500 stocks and some SPDR ETFs."""
   time_slices = [
       (datetime(1999, 1, 1), datetime(2004, 1, 1), datetime(2004, 1, 2)),
@@ -123,17 +124,17 @@
       ]
 
   url = 'http://localhost:7070'
-  client = predictionio.EventClient(app_id=app_id, threads=1, url=url)
+  client = predictionio.EventClient(access_key=access_key, threads=1, url=url)
 
   tickers = SP500_LIST + ETF_LIST 
 
   for ticker in tickers:
     for time_slice in time_slices:
-      import_data(client, app_id, ticker, 
+      import_data(client, access_key, ticker, 
           time_slice[0], time_slice[1], time_slice[2])
 
 
-def import_data_with_gaps(app_id):
+def import_data_with_gaps(access_key):
   """This method import data with time gaps. 
   
   Data imported by this method is used by stock engine, it demonsrates how it
@@ -154,11 +155,11 @@
   tickers = ['SPY', 'AAPL', 'IBM', 'MSFT']
  
   url = 'http://localhost:7070'
-  client = predictionio.EventClient(app_id=app_id, threads=1, url=url)
+  client = predictionio.EventClient(access_key=access_key, threads=1, url=url)
 
   for ticker in tickers:
     for time_slice in time_slices:
-      import_data(client, app_id, ticker, 
+      import_data(client, access_key, ticker, 
           time_slice[0], time_slice[1], time_slice[2])
 
   # below are data with holes
@@ -171,7 +172,7 @@
   tickers = ['AMZN']
   for ticker in tickers:
     for time_slice in time_slices:
-      import_data(client, app_id, ticker, 
+      import_data(client, access_key, ticker, 
           time_slice[0], time_slice[1], time_slice[2])
 
   time_slices = [
@@ -181,11 +182,11 @@
   tickers = ['FB']
   for ticker in tickers:
     for time_slice in time_slices:
-      import_data(client, app_id, ticker, 
+      import_data(client, access_key, ticker, 
           time_slice[0], time_slice[1], time_slice[2])
 
 
-def import_one(app_id):
+def import_one(access_key):
   """Import TSLA.
   
   Import data with from 2014-01-01 until 2014-03-01. event_time specifies when
@@ -197,12 +198,16 @@
   ticker = 'TSLA'
  
   url = 'http://localhost:7070'
-  client = predictionio.EventClient(app_id=app_id, threads=1, url=url)
+  client = predictionio.EventClient(access_key=access_key, threads=1, url=url)
 
-  import_data(client, app_id, ticker, start_time, end_time, event_time)
+  import_data(client, access_key, ticker, start_time, end_time, event_time)
 
 
 if __name__ == '__main__':
-  #import_all(app_id=2)
-  import_data_with_gaps(app_id=1)
-  #import_one(app_id=1)
+  if len(sys.argv) < 2:
+    sys.exit("Usage: python -m examples.import_yahoo <access_key>")
+
+  access_key = sys.argv[1]
+  import_all(access_key=access_key)
+  #import_data_with_gaps(access_key=access_key)
+  #import_one(access_key=access_key)
diff --git a/examples/itemrank_quick_start.py b/examples/itemrank_quick_start.py
index b76abc1..846d1d5 100644
--- a/examples/itemrank_quick_start.py
+++ b/examples/itemrank_quick_start.py
@@ -5,12 +5,13 @@
 import predictionio
 
 import random
+import sys
 
-def import_itemrank(app_id):
+def import_itemrank(access_key):
 
   random.seed()
   
-  client = predictionio.EventClient(app_id=app_id)
+  client = predictionio.EventClient(access_key)
 
   print client.get_status()
   
@@ -39,4 +40,6 @@
 
 
 if __name__ == '__main__':
-  import_itemrank(7)
+  if len(sys.argv) < 2:
+    sys.exit("Usage: python -m examples.itemrank_quick_start <access_key>")
+  import_itemrank(sys.argv[1])
diff --git a/predictionio/__init__.py b/predictionio/__init__.py
index 3b6fe00..ecb6f27 100644
--- a/predictionio/__init__.py
+++ b/predictionio/__init__.py
@@ -5,7 +5,7 @@
 """
 
 
-__version__ = "0.8.1"
+__version__ = "0.8.2"
 
 # import deprecated libraries.
 from predictionio.obsolete import Client
@@ -151,7 +151,10 @@
 class EventClient(BaseClient):
   """Client for importing data into PredictionIO Event Server.
 
-  :param app_id: the id used to identify application data.
+  Notice that app_id has been deprecated as of 0.8.2. Please use access_token
+  instead.
+
+  :param access_key: the access key for your application.
   :param url: the url of PredictionIO Event Server.
   :param threads: number of threads to handle PredictionIO API requests.
           Must be >= 1.
@@ -162,13 +165,24 @@
   :param timeout: timeout for HTTP connection attempts and requests in
     seconds (optional).
     Default value is 5.
-
   """
 
-  def __init__(self, app_id, url="http://localhost:7070",
+  def __init__(self, access_key, 
+      url="http://localhost:7070",
       threads=1, qsize=0, timeout=5):
+    assert type(access_key) is str, ("access_key must be string. "
+        "Notice that app_id has been deprecated in Prediction.IO 0.8.2. "
+        "Please use access_key instead.")
+
     super(EventClient, self).__init__(url, threads, qsize, timeout)
-    self.app_id = app_id
+
+    if len(access_key) <= 8:
+      raise DeprecationWarning(
+          "It seems like you are specifying an app_id. It is deprecated in "
+          "Prediction.IO 0.8.2. Please use access_key instead. Or, "
+          "you may use an earlier version of this sdk.")
+
+    self.access_key = access_key
 
   def acreate_event(self, event, entity_type, entity_id,
       target_entity_type=None, target_entity_id=None, properties=None,
@@ -194,7 +208,6 @@
       object to get the final resuls or status of this asynchronous request.
     """
     data = {
-        "appId": self.app_id,
         "event": event,
         "entityType": entity_type,
         "entityId": entity_id,
@@ -215,7 +228,7 @@
     et_str = et.strftime("%Y-%m-%dT%H:%M:%S.%f")[:-3] + et.strftime("%z")
     data["eventTime"] = et_str
     
-    path = "/events.json"
+    path = "/events.json?accessKey=" + self.access_key
     request = AsyncRequest("POST", path, **data)
     request.set_rfunc(self._acreate_resp)
     self._connection.make_request(request)
diff --git a/setup.py b/setup.py
index 8a98273..48ce914 100644
--- a/setup.py
+++ b/setup.py
@@ -10,7 +10,7 @@
 
 setup(
     name='PredictionIO',
-    version="0.8.1",
+    version="0.8.2",
     author=__author__,
     author_email=__email__,
     packages=['predictionio'],