Added routines for managing interactions with agents for supporting P…

…OST and delete operations

Signed-off-by: Christian Pinto <christian.pinto@ibm.com>

api_emulator/agents_management.py

@@ -0,0 +1,54 @@
+import json
+import api_emulator.utils as utils
+import requests
+
+# This function checks if an object is managed by a Sunfish agent and returns
+# the Agent @odata.id or None if the object is not managed by an Agent
+# We are assuming that the resource_path we receive is always that of a collection because according to the RedFish
+# specification (v1.18.0 at the time of writing this comment): "To create a resource, services shall support the POST
+# method on resource collections."
+def isAgentManaged(resource_path):
+    resource = utils.get_object(resource_path)
+    if "oem" in resource and "Sunfish_RM" in resource["oem"] and "ManagingAgent" in resource["oem"]["Sunfish_RM"]:
+        return resource["oem"]["Sunfish_RM"]["ManagingAgent"]["@odata.id"]
+
+    return None
+
+def requestToAgent(method, agent_id, resource_path, payload):
+    if agent_id is None or agent_id == "":
+        raise Exception("Error: Missing Agent id")
+    if resource_path is None or resource_path == "":
+        raise Exception("Error: Missing resource_path")
+
+    agent = utils.get_object(agent_id)
+    agent_hostname = agent["HostName"]
+    resource_uri = agent_hostname + "/" + resource_path
+    if method == "POST":
+        if payload is None:
+            # we only check if there is a payload and we assume that is correct
+            raise Exception("Error: Missing payload")
+        headers = {
+            'Content-Type': 'application/json'
+        }
+        r = requests.post(resource_uri, headers=headers, data=json.dumps(payload))
+    elif method == "DELETE":
+        r = requests.delete(resource_uri)
+    else:
+        raise Exception("Invalid method for requestToAgent")
+
+    return r
+
+# This method forwards the request to the agent specified in the arguments and returns an object config dict
+# updated with the OEM field pointing to the management server.
+# The function returns:
+#   - (None, None) if the resource is not managed by an agent
+#   - (agent id, (reason, status code)) if agent managed and returning the message from the agent
+def forwardToAgentIfManaged(method, resource_path, config=None):
+    agent = isAgentManaged(resource_path)
+    if agent:
+        # This collection is managed by an agent, let's forward the request
+        # We just return whatever the agent returns to us
+        r = requestToAgent(method, agent, resource_path, config)
+        return agent, (r.reason, r.status_code)
+
+    return None, None