feat: add sampling for on_delivery_complete (#60)

Author: VivekPipaliya23

apps/vmq_events_sidecar/priv/vmq_events_sidecar.schema

@@ -73,3 +73,13 @@
     vmq_schema_translate:translate_sampling("on_deliver", Conf)
   end
 }.
+
+%% @doc Configure the sampling for on_delivery_complete events based on ACL names
+{mapping, "sample.on_delivery_complete.$acl.percentage", "vmq_events_sidecar.sampler.on_delivery_complete", 
+ [{datatype, integer}]}.
+
+{translation, "vmq_events_sidecar.sampler.on_delivery_complete",
+  fun(Conf) ->
+    vmq_schema_translate:translate_sampling("on_delivery_complete", Conf)
+  end
+}.

apps/vmq_events_sidecar/src/vmq_events_sidecar_cli.erl

@@ -206,7 +206,8 @@ hook_sampling_keyspec() ->
                         Hook,
                         [
                             "on_publish",
-                            "on_deliver"
+                            "on_deliver",
+                            "on_delivery_complete"
                         ]
                     )
                 of
@@ -308,7 +309,7 @@ events_sampling_usage() ->
 enable_sampling_usage() ->
     [
         "vmq-admin events sampling enable hook=<Hook> percentage=<Percentage> acl_name=<ACL>\n\n",
-        "  Enables sampling based on acl_name/label for on_publish & on_deliver.",
+        "  Enables sampling based on acl_name/label for on_publish, on_deliver & on_delivery_complete.",
         "\n\n"
     ].
 

apps/vmq_events_sidecar/src/vmq_events_sidecar_plugin.erl

@@ -85,14 +85,20 @@ enable_event(HookName) when is_atom(HookName) ->
 disable_event(HookName) when is_atom(HookName) ->
     gen_server:call(?MODULE, {disable_event, HookName}).
 
--spec enable_sampling(Hook :: on_publish | on_deliver, Criterion :: binary(), Percent :: integer()) ->
+-spec enable_sampling(
+    Hook :: on_publish | on_deliver | on_delivery_complete,
+    Criterion :: binary(),
+    Percent :: integer()
+) ->
     ok.
 enable_sampling(Hook, Criterion, Percent) when
     is_atom(Hook) and is_binary(Criterion) and is_integer(Percent)
 ->
     gen_server:call(?MODULE, {enable_sampling, Hook, Criterion, Percent}).
 
--spec disable_sampling(Hook :: on_publish | on_deliver, Criterion :: binary()) ->
+-spec disable_sampling(
+    Hook :: on_publish | on_deliver | on_delivery_complete, Criterion :: binary()
+) ->
     ok | {error, not_found}.
 disable_sampling(Hook, Criterion) when is_atom(Hook) and is_binary(Criterion) ->
     gen_server:call(?MODULE, {disable_sampling, Hook, Criterion}).
@@ -107,7 +113,7 @@ all_hooks() ->
         ?TBL
     ).
 
--spec list_sampling_conf(Hook :: on_publish | on_deliver) -> [term()].
+-spec list_sampling_conf(Hook :: on_publish | on_deliver | on_delivery_complete) -> [term()].
 list_sampling_conf(Hook) ->
     ets:match(?SAMPLER_TBL, {{Hook, '$1'}, '$2'}).
 
@@ -319,12 +325,22 @@ on_deliver(
     username(), subscriber_id(), qos(), topic(), payload(), flag(), matched_acl(), flag()
 ) ->
     'next'.
-on_delivery_complete(UserName, SubscriberId, QoS, Topic, Payload, IsRetain, MatchedAcl, Persisted) ->
+on_delivery_complete(
+    UserName,
+    SubscriberId,
+    QoS,
+    Topic,
+    Payload,
+    IsRetain,
+    #matched_acl{name = ACL} = MatchedAcl,
+    Persisted
+) ->
     {MP, ClientId} = subscriber_id(SubscriberId),
     send_event(
         on_delivery_complete,
         {MP, ClientId, normalise(UserName), QoS, unword(Topic), Payload, IsRetain, MatchedAcl,
-            Persisted}
+            Persisted},
+        ACL
     ).
 
 -spec on_offline_message(subscriber_id(), qos(), topic(), payload(), flag()) -> 'next'.
@@ -474,6 +490,8 @@ sample(Hook, Criterion) ->
             check(Hook, Criterion);
         on_deliver ->
             check(Hook, Criterion);
+        on_delivery_complete ->
+            check(Hook, Criterion);
         _ ->
             true
     end.

apps/vmq_events_sidecar/src/vmq_events_sidecar_sup.erl

@@ -35,7 +35,8 @@ start_link() ->
                 ),
                 SamplingHooks = [
                     on_publish,
-                    on_deliver
+                    on_deliver,
+                    on_delivery_complete
                 ],
                 lists:foreach(
                     fun