[edk2-redfish-client][PATCH 4/6] Tool/Redfish-Profile-Simulator: Add ETag support

["Nickle Wang" <nicklew@nvidia.com>]

Implement ETag support in HTTP header

Signed-off-by: Nickle Wang <nicklew@nvidia.com>
Cc: Abner Chang <abner.chang@amd.com>
Cc: Igor Kulchytskyy <igork@ami.com>
---
 .../v1sim/resource.py                         | 10 +++++--
 .../v1sim/systems.py                          | 28 +++++++++++--------
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/Tools/Redfish-Profile-Simulator/v1sim/resource.py b/Tools/Redfish-Profile-Simulator/v1sim/resource.py
index e722d16a..0c7a8382 100644
--- a/Tools/Redfish-Profile-Simulator/v1sim/resource.py
+++ b/Tools/Redfish-Profile-Simulator/v1sim/resource.py
@@ -36,6 +36,12 @@ class RfResource:
             self.final_init_processing(base_path, rel_path)
         else:
             self.res_data = {}
+        self.generate_etag(json.dumps(self.res_data))
+
+    def generate_etag(self, context):
+        md5 = hashlib.md5()
+        md5.update(context.encode('utf-8'))
+        self.etag = 'W/"' + md5.hexdigest() + '"'
 
     def create_sub_objects(self, base_path, rel_path):
         pass
@@ -49,8 +55,8 @@ class RfResource:
             # SHA1 should generate well-behaved etags
             response = flask.make_response(self.response)
             response.mimetype = 'application/json'
-            etag = hashlib.sha1(self.response.encode('utf-8')).hexdigest()
-            response.set_etag(etag)
+            response.headers["ETag"] = self.etag
+
             return response
         except KeyError:
             flask.abort(404)
diff --git a/Tools/Redfish-Profile-Simulator/v1sim/systems.py b/Tools/Redfish-Profile-Simulator/v1sim/systems.py
index 6305a51e..5adf81be 100644
--- a/Tools/Redfish-Profile-Simulator/v1sim/systems.py
+++ b/Tools/Redfish-Profile-Simulator/v1sim/systems.py
@@ -92,7 +92,11 @@ class RfSystemObj(RfResource):
             if "BootOrder" in boot_data:
                 self.res_data['Boot']['BootOrder'] = boot_data['BootOrder']
 
-        resp = flask.Response(json.dumps(self.res_data,indent=4), mimetype="application/json")
+        context = json.dumps(self.res_data,indent=4)
+        self.generate_etag(context)
+        resp = flask.Response(context, mimetype="application/json")
+        resp.headers["ETag"] = self.etag
+
         return 0, 200, None, resp
 
     def reset_resource(self, reset_data):
@@ -136,26 +140,28 @@ class RfMemoryCollection(RfCollection):
 
         post_data["@odata.id"] = newMemoryUrl
 
-        md5 = hashlib.md5()
-        md5.update(json.dumps(post_data).encode("utf-8"))
-        etag_str = 'W/"' + md5.hexdigest() + '"'
-        post_data["@odata.etag"] = etag_str
+        self.generate_etag(json.dumps(post_data,indent=4))
+
+        post_data["@odata.etag"] = self.etag
         self.elements[str(newMemoryIdx)] = post_data
 
         resp = flask.Response(json.dumps(post_data,indent=4), mimetype="application/json")
         resp.headers["Location"] = newMemoryUrl
-        resp.headers["ETag"] = etag_str
-
+        resp.headers["ETag"] = self.etag
         return 0, 200, None, resp
 
     def patch_memory(self, Idx, patch_data):
-        md5 = hashlib.md5()
-        md5.update(json.dumps(patch_data).encode("utf-8"))
-        etag_str = 'W/"' + md5.hexdigest() + '"'
-        patch_data["@odata.etag"] = etag_str
 
+
+        self.elements[str(Idx)] = {**self.elements[str(Idx)], **patch_data}
+
+        context = json.dumps(self.elements[str(Idx)],indent=4)
+        self.generate_etag(context)
+        patch_data["@odata.etag"] = self.etag
         self.elements[str(Idx)] = {**self.elements[str(Idx)], **patch_data}
+
         resp = flask.Response(json.dumps(self.elements[str(Idx)],indent=4), mimetype="application/json")
+        resp.headers["ETag"] = self.etag
         return 0, 200, None, resp
 
     def get_memory(self, Idx):
-- 
2.17.1