Add API example for fetching historical messages.

Fixes: #269.

MANIFEST.in

@@ -8,3 +8,4 @@ include examples/unsubscribe
 include examples/list-members
 include examples/list-subscriptions
 include examples/print-messages
+include examples/recent-messages

examples/recent-messages

@@ -0,0 +1,61 @@
+#!/usr/bin/env python2.7
+# -*- coding: utf-8 -*-
+
+# Copyright © 2012 Zulip, Inc.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+from __future__ import print_function
+import sys
+import os
+import json
+import optparse
+
+usage = """recent-messages [options] --count=<no. of previous messages> --user=<sender's email address> --api-key=<sender's api key>
+
+Prints out last count messages recieved by the indicated bot or user
+
+Example: recent-messages --count=101 --user=username@example.com --api-key=a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5
+
+You can omit --user and --api-key arguments if you have a properly set up ~/.zuliprc
+"""
+sys.path.append(os.path.join(os.path.dirname(__file__), '..'))
+import zulip
+
+parser = optparse.OptionParser(usage=usage)
+parser.add_option('--count', default=100)
+parser.add_option_group(zulip.generate_option_group(parser))
+(options, args) = parser.parse_args()
+
+client = zulip.init_from_options(options)
+
+req = {
+    'narrow': [["stream", "Denmark"]],
+    'num_before': options.count,
+    'num_after': 0,
+    'anchor': 1000000000,
+    'apply_markdown': False
+}
+
+old_messages = client.do_api_query(req, zulip.API_VERSTRING + 'messages', method='GET')
+if 'messages' in old_messages:
+    for message in old_messages['messages']:
+        print(json.dumps(message, indent=4))
+else:
+    print([])

setup.py

@@ -40,7 +40,7 @@ package_info = dict(
     data_files=[('share/zulip/examples', ["examples/zuliprc", "examples/send-message", "examples/subscribe",
                                            "examples/get-public-streams", "examples/unsubscribe",
                                            "examples/list-members", "examples/list-subscriptions",
-                                           "examples/print-messages"])] + \
+                                           "examples/print-messages", "examples/recent-messages"])] + \
         list(recur_expand('share/zulip', 'integrations/')),
     scripts=["bin/zulip-send"],
 )