Make it possible to configure randomized startup delay range via new style config

Author: michaelklishin

priv/schema/rabbit.schema

@@ -833,6 +833,32 @@ fun(Conf) ->
     end
 end}.
 
+%% Cluster formation: Randomized startup delay
+
+{mapping, "cluster_formation.randomized_startup_delay_range.min", "rabbit.cluster_formation.randomized_delay_range",
+    [{datatype, integer}]}.
+{mapping, "cluster_formation.randomized_startup_delay_range.max", "rabbit.cluster_formation.randomized_delay_range",
+    [{datatype, integer}]}.
+
+{translation, "rabbit.cluster_formation.randomized_delay_range",
+fun(Conf) ->
+    Min = cuttlefish:conf_get("cluster_formation.randomized_startup_delay_range.min", Conf, undefined),
+    Max = cuttlefish:conf_get("cluster_formation.randomized_startup_delay_range.max", Conf, undefined),
+
+    case {Min, Max} of
+        {undefined, undefined} ->
+            cuttlefish:unset();
+        {undefined, Max}       ->
+            %% fallback default
+            {5, Max};
+        {Min, undefined}       ->
+            %% fallback default
+            {Min, 60};
+        {Min, Max}             ->
+            {Min, Max}
+    end
+end}.
+
 %% Classic config-driven peer discuvery backend.
 %%
 %% Make clustering happen *automatically* at startup - only applied

test/config_schema_SUITE_data/rabbit.snippets

@@ -372,6 +372,29 @@ tcp_listen_options.exit_on_close = false",
   "tcp_listen_options.linger.timeout = 100",
   [{rabbit,[{tcp_listen_options,[{linger,{false,100}}]}]}],
   []},
+
+ {cluster_formation_randomized_startup_delay_both_values,
+  "cluster_formation.randomized_startup_delay_range.min = 10
+   cluster_formation.randomized_startup_delay_range.max = 30",
+  [{rabbit, [{cluster_formation, [
+                                  {randomized_delay_range, {10, 30}}
+                                  ]}]}],
+  []},
+
+ {cluster_formation_randomized_startup_delay_min_only,
+  "cluster_formation.randomized_startup_delay_range.min = 10",
+  [{rabbit, [{cluster_formation, [
+                                  {randomized_delay_range, {10, 60}}
+                                  ]}]}],
+  []},
+
+ {cluster_formation_randomized_startup_delay_max_only,
+  "cluster_formation.randomized_startup_delay_range.max = 30",
+  [{rabbit, [{cluster_formation, [
+                                  {randomized_delay_range, {5, 30}}
+                                  ]}]}],
+  []},
+
  {cluster_formation_dns,
   "cluster_formation.peer_discovery_backend = rabbit_peer_discovery_dns
    cluster_formation.dns.hostname = 192.168.0.2.xip.io