do not start service if not present in configuration file

src/mongoose_service.erl

@@ -53,8 +53,10 @@ start() ->
 -spec stop() -> ok.
 stop() -> catch ets:delete(?ETAB), ok.
 
--spec start_service(service(), options()) -> ok | {error, already_started}.
-start_service(Service, Opts) ->
+-spec start_service(service(), options() | undefined) -> ok | {error, already_started}.
+start_service(Service, undefined) ->
+    error({service_not_configured, Service});
+start_service(Service, Opts) when is_list(Opts) ->
     case is_loaded(Service) of
         true -> {error, already_started};
         false -> run_start_service(Service, Opts)
@@ -74,7 +76,7 @@ ensure_loaded(Service) ->
             ok;
         false ->
             Options = ejabberd_config:get_local_option_or_default(services, []),
-            start_service(Service, proplists:get_value(Service, Options, [])),
+            start_service(Service, proplists:get_value(Service, Options)),
             ok
     end.
 

test/mongoose_service_SUITE.erl

@@ -15,7 +15,8 @@ all() ->
         ensure,
         verify_deps,
         start_deps,
-        module_deps
+        module_deps,
+        misconfigured
     ].
 
 services() -> [service_a, service_b, service_c, service_d, service_e, service_f, service_g,
@@ -50,6 +51,15 @@ service_deps() ->
         {service_l, [service_k]}
     ].
 
+init_per_testcase(misconfigured, C) ->
+    mongoose_service:start(),
+    meck:new(ejabberd_config, [passthrough]),
+    meck:expect(ejabberd_config, get_local_option_or_default,
+        fun(services, _) -> [{service_a, []}] end),
+    meck:new(service_a, [non_strict]),
+    meck:expect(service_a, deps, fun() -> [service_b] end),
+    C;
+
 init_per_testcase(module_deps, C) ->
     init_per_testcase(generic, C),
     meck:expect(ejabberd_config, get_local_option, fun(_) -> undefined end),
@@ -79,6 +89,11 @@ init_per_testcase(_, C) ->
               proplists:get_keys(service_deps())),
     C.
 
+end_per_testcase(misconfigured, C) ->
+    meck:unload(service_a),
+    meck:unload(ejabberd_config),
+    C;
+
 end_per_testcase(module_deps, C) ->
     meck:unload(module_a),
     end_per_testcase(generic, C);
@@ -161,6 +176,10 @@ module_deps(_) ->
     ?assert(gen_mod:is_loaded(<<"localhost">>, module_a)),
     ok.
 
+misconfigured(_) ->
+    ?assertError({service_not_configured, service_b}, mongoose_service:ensure_loaded(service_a)),
+    ok.
+
 
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