Allow testing for server versions

badgekit/api.py

@@ -1,6 +1,7 @@
 import requests
 import posixpath
 from . import jwt_auth
+from distutils.version import StrictVersion
 try:
     from urlparse import urljoin
     from urllib import urlencode
@@ -257,3 +258,19 @@ def _json_loads(self, text):
             return json.loads(text)
         except ValueError as e:
             raise APIError("Invalid JSON in BadgeKit response")
+
+    def server_version(self):
+        """Returns the server's reported version as a string."""
+        resp = requests.get(urljoin(self.baseurl, '/'), auth=self.auth)
+        resp_dict = self._json_loads(resp.text)
+        return resp_dict['version']
+
+    def require_server_version(self, required_version):
+        version = self.server_version()
+        server_url = self.baseurl
+        if StrictVersion(version) < StrictVersion(required_version):
+            raise ValueError(
+                    ("Version {required_version} or greater "
+                    + "of BadgeKit-API server required, but "
+                    + "{server_url} is only version {version}.")
+                    .format(**locals()))

test/api_test.py

@@ -106,6 +106,37 @@ def test_query(self):
                 'systems/jkl/badges?archived=true')
 
 
+class ServerVersionTest(unittest.TestCase):
+    @httpretty.activate
+    def test_find_version(self):
+        a = badgekit.BadgeKitAPI('http://example.com', 'asdf')
+
+        httpretty.register_uri(httpretty.GET,
+                re.compile('example.com/.*'),
+                body='{"app":"BadgeKit API","version":"0.2.9"}')
+
+        resp = a.server_version()
+        self.assertEqual(resp, "0.2.9")
+
+
+    @httpretty.activate
+    def test_require_version(self):
+        a = badgekit.BadgeKitAPI('http://example.com', 'asdf')
+
+        httpretty.register_uri(httpretty.GET,
+                re.compile('example.com/.*'),
+                body='{"app":"BadgeKit API","version":"0.2.9"}')
+
+        try:
+            a.require_server_version("0.3.0")
+            self.fail("Should have thrown exception")
+        except ValueError:
+            pass
+
+        a.require_server_version("0.2")
+        a.require_server_version("0.2.2")
+
+
 class ExceptionTest(unittest.TestCase):
     def test_known_str(self):
         req = requests.Request("POST", "http://example.org/system/")