Initial implementation of Gerrit REST API interface

This initial version implements wrappers for GET, PUT, POST
and DELETE requests.

Authentication is not implemented. All requests are sent
anonymously.

Handling of error responses is not implemented.

This change introduces a dependency on python-requests.

Change-Id: I579f9f02be8afbb4e720daf97ca873d77cd54a77

3 files changed, 112 insertions, 1 deletions

diff --git a/pygerrit/rest/__init__.py b/pygerrit/rest/__init__.py
new file mode 100644
index 0000000..1e4b25f
--- /dev/null
+++ b/pygerrit/rest/__init__.py
@@ -0,0 +1,110 @@
+# The MIT License
+#
+# Copyright 2013 Sony Mobile Communications. All rights reserved.
+#
+# 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.
+
+""" Interface to the Gerrit REST API. """
+
+import json
+import requests
+
+GERRIT_MAGIC_JSON_PREFIX = ")]}\'\n"
+
+
+def _decode_response(response):
+    """ Decode the `response` received from a REST API call.
+
+    Strip off Gerrit's magic prefix if it is there, and return decoded
+    JSON content or raw text if it cannot be decoded as JSON.
+
+    """
+    content = response.content
+    if content.startswith(GERRIT_MAGIC_JSON_PREFIX):
+        content = content[len(GERRIT_MAGIC_JSON_PREFIX):]
+    try:
+        return json.loads(content)
+    except ValueError:
+        return content.strip()
+
+
+class GerritRestAPI(object):
+
+    """ Interface to the Gerrit REST API. """
+
+    def __init__(self, url):
+        """ Constructor.
+
+        `url` is assumed to be the full URL to the server, including the
+        'http(s)://' prefix.
+
+        """
+        self.kwargs = {}
+        self.url = url
+        self.session = requests.session()
+
+    def _get(self, endpoint, params=None):
+        """ Send HTTP GET to `endpoint`.
+
+        Return JSON decoded result.
+
+        """
+        kwargs = self.kwargs.copy()
+        if params:
+            kwargs['params'] = params
+        response = self.session.get(self.url + endpoint, **kwargs)
+        return _decode_response(response)
+
+    def _put(self, endpoint, params=None, data=None):
+        """ Send HTTP PUT to `endpoint`.
+
+        Return JSON decoded result.
+
+        """
+        kwargs = self.kwargs.copy()
+        if params:
+            kwargs['params'] = params
+        if data:
+            kwargs['data'] = data
+        response = self.session.put(self.url + endpoint, **kwargs)
+        return _decode_response(response)
+
+    def _post(self, endpoint, params=None, data=None):
+        """ Send HTTP POST to `endpoint`.
+
+        Return JSON decoded result.
+
+        """
+        kwargs = self.kwargs.copy()
+        if params:
+            kwargs['params'] = params
+        if data:
+            kwargs['data'] = data
+        response = self.session.post(self.url + endpoint, **kwargs)
+        return _decode_response(response)
+
+    def _delete(self, endpoint):
+        """ Send HTTP DELETE to `endpoint`.
+
+        Return JSON decoded result.
+
+        """
+        kwargs = self.kwargs.copy()
+        response = self.session.delete(self.url + endpoint, **kwargs)
+        return _decode_response(response)
diff --git a/requirements.txt b/requirements.txt
index 1b918a7..edc8a50 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,3 @@
 paramiko==1.11.0
 pycrypto==2.3
+requests==1.2.3
diff --git a/setup.py b/setup.py
index 058e9f0..b6e9206 100755
--- a/setup.py
+++ b/setup.py
@@ -29,7 +29,7 @@ from setuptools import setup
 
 from pygerrit import __version__
 
-REQUIRES = ['paramiko==1.11.0', 'pycrypto==2.3']
+REQUIRES = ['paramiko==1.11.0', 'pycrypto==2.3', 'requests==1.2.3']
 
 
 def _main():