[api][s3g] OPSAPS-39155 Python client changes for

Prune command

This change adds a new 'command by name' endpoint
to external accounts that would be used to invoke
S3PruneCommand

Testing done:
-make clean; python setup.py install; make test; make dist;
-Using a Python script, tested that S3GuardPrune works
on a cdep cluster.

Author: Aravind Selvan

python/src/cm_api/endpoints/external_accounts.py

@@ -192,3 +192,14 @@ def update_config(self, config):
     @return: Dictionary with updated configuration.
     """
     return self._update_config("config", config)
+
+  def external_account_cmd_by_name(self, command_name):
+    """
+    Executes a command on the external account specified
+    by name.
+
+    @param command_name: The name of the command.
+    @return: Reference to the submitted command.
+    @since: API v16
+    """
+    return self._cmd(command_name, data=self.name, api_version=16)

python/src/cm_api_tests/test_external_accounts.py

@@ -188,3 +188,12 @@ def test_update_acct_config(self):
         self.assertTrue(entry[1] == 'foo')
       else:
         self.assertFailure()
+
+  def test_s3_guard_prune_cmd(self):
+    command_name = 'S3GuardPrune'
+    data = '"test1"'
+    self.resource.expect("POST",
+                         "/externalAccounts/account/%s/commands/%s" % ('test1', command_name),
+                         data=data, retdata={'name' : 'S3GuardPrune'})
+    resp = self.account.external_account_cmd_by_name(command_name)
+    self.assertEquals('S3GuardPrune', resp.name)