Proof of concept API quality checking

contrib/lint.py

@@ -0,0 +1,104 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+libcloud linter
+
+This script checks the libcloud codebase for registered drivers that don't
+comply to libcloud API guidelines.
+"""
+
+import inspect
+import os
+
+import libcloud
+
+import libcloud.compute.providers
+from libcloud.compute.base import NodeDriver
+
+import libcloud.dns.providers
+from libcloud.dns.base import DNSDriver
+
+import libcloud.loadbalancer.providers
+from libcloud.loadbalancer.base import Driver
+
+import libcloud.storage.providers
+from libcloud.storage.base import StorageDriver
+
+
+modules = [
+    (libcloud.compute.providers, NodeDriver),
+    (libcloud.dns.providers, DNSDriver),
+    (libcloud.loadbalancer.providers, Driver),
+    (libcloud.storage.providers, StorageDriver),
+    ]
+
+
+warnings = set()
+
+def warning(obj, warning):
+    source_file = os.path.relpath(inspect.getsourcefile(obj), os.path.dirname(libcloud.__file__))
+    source_line = inspect.getsourcelines(obj)[1]
+    if (source_file, source_line, warning) in warnings:
+        # When the error is actually caused by a mixin or base class we can get dupes...
+        return
+    warnings.add((source_file, source_line, warning))
+    print source_file, source_line, warning
+
+for providers, base, in modules:
+    core_api = {}
+    for name, value in inspect.getmembers(base, inspect.ismethod):
+        if name.startswith("_"):
+            continue
+
+        if name.startswith("ex_"):
+            warning(value, "Core driver shouldn't haveex_ methods")
+            continue
+
+        args = core_api[name] = inspect.getargspec(value)
+
+        for arg in args.args:
+            if arg.startswith("ex_"):
+                warning(value, "Core driver method shouldnt have ex_ arguments")
+
+
+    for driver_id in providers.DRIVERS.keys():
+        driver = providers.get_driver(driver_id)    
+
+        for name, value in inspect.getmembers(driver, inspect.ismethod):
+            if name.startswith("_"):
+                continue
+
+            if not name.startswith("ex_") and not name in core_api:
+                warning(value, "'%s' should be prefixed with ex_ or be private as it is not a core API" % name)
+                continue
+
+
+            # Only validate arguments of core API's
+            if name.startswith("ex_"):
+                continue
+
+            argspec = inspect.getargspec(value)
+
+            core_args = set(core_api[name].args)
+            driver_args = set(argspec.args)
+
+            for missing in core_args - driver_args:
+                warning(value, "Core API function should support arg '%s' but doesn't" % missing)
+
+            for extra in driver_args - core_args:
+                if not extra.startswith("ex_"):
+                    warning(value, "Core API function shouldn't take arg '%s'. Should it be prefixed with ex_?" % extra)
+