client: add support for pre-schema servers

Bundle remote plugin interface definitions for servers which lack API
schema support. These server API versions are included:
* 2.49: IPA 3.1.0 on RHEL/CentOS 6.5+,
* 2.114: IPA 4.1.4 on Fedora 22,
* 2.156: IPA 4.2.0 on RHEL/CentOS 7.2 and IPA 4.2.4 on Fedora 23,
* 2.164: IPA 4.3.1 on Fedora 23.

For servers with other API versions, the closest lower API version is used.

https://fedorahosted.org/freeipa/ticket/4739

Reviewed-By: David Kupka <dkupka@redhat.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/ipaclient/remote_plugins/compat.py b/ipaclient/remote_plugins/compat.py
new file mode 100644
index 000000000..40521af45
--- /dev/null
+++ b/ipaclient/remote_plugins/compat.py
@@ -0,0 +1,76 @@
+#
+# Copyright (C) 2016  FreeIPA Contributors see COPYING for license
+#
+
+from distutils.version import LooseVersion
+import importlib
+import os
+import re
+import sys
+
+import six
+
+from ipaclient.frontend import ClientCommand, ClientMethod
+from ipalib.frontend import Object
+
+if six.PY3:
+    unicode = str
+
+
+class CompatCommand(ClientCommand):
+    @property
+    def forwarded_name(self):
+        return self.name
+
+
+class CompatMethod(ClientMethod, CompatCommand):
+    pass
+
+
+class CompatObject(Object):
+    pass
+
+
+def get_package(api, client):
+    if not client.isconnected():
+        client.connect(verbose=False)
+
+    env = client.forward(u'env', u'api_version', version=u'2.0')
+    try:
+        server_version = env['result']['api_version']
+    except KeyError:
+        ping = client.forward(u'ping', u'api_version', version=u'2.0')
+        try:
+            match = re.search(u'API version (2\.[0-9]+)', ping['summary'])
+        except KeyError:
+            match = None
+        if match is not None:
+            server_version = match.group(1)
+        else:
+            server_version = u'2.0'
+    server_version = LooseVersion(server_version)
+
+    package_names = {}
+    base_name = __name__.rpartition('.')[0]
+    base_dir = os.path.dirname(__file__)
+    for name in os.listdir(base_dir):
+        package_dir = os.path.join(base_dir, name)
+        if name.startswith('2_') and os.path.isdir(package_dir):
+            package_version = name.replace('_', '.')
+            package_names[package_version] = '{}.{}'.format(base_name, name)
+
+    package_version = None
+    for version in sorted(package_names, key=LooseVersion):
+        if (package_version is None or
+                LooseVersion(package_version) < LooseVersion(version)):
+            package_version = version
+        if LooseVersion(version) >= server_version:
+            break
+
+    package_name = package_names[package_version]
+    try:
+        package = sys.modules[package_name]
+    except KeyError:
+        package = importlib.import_module(package_name)
+
+    return package