fix: erase persistent terms on app stop

apps/opentelemetry/src/opentelemetry_app.erl

@@ -54,6 +54,8 @@ start(_StartType, _StartArgs) ->
     end.
 
 stop(_State) ->
+    _ = opentelemetry:cleanup_persistent_terms(),
+    _ = otel_span_limits:cleanup_persistent_terms(),
     ok.
 
 %% internal functions

apps/opentelemetry/src/otel_span_limits.erl

@@ -25,15 +25,16 @@
          event_count_limit/0,
          link_count_limit/0,
          attribute_per_event_limit/0,
-         attribute_per_link_limit/0]).
+         attribute_per_link_limit/0,
+         cleanup_persistent_terms/0]).
 
 -include("otel_span.hrl").
 
 -define(SPAN_LIMITS_KEY, {?MODULE, span_limits}).
 
 -spec get() -> #span_limits{}.
 get() ->
-    persistent_term:get(?SPAN_LIMITS_KEY).
+    persistent_term:get(?SPAN_LIMITS_KEY, #span_limits{}).
 
 -spec set(otel_configuration:t()) -> ok.
 set(#{attribute_count_limit := AttributeCountLimit,
@@ -80,3 +81,6 @@ get_limit(attribute_per_event_limit, #span_limits{attribute_per_event_limit=Attr
     AttributePerEventLimit;
 get_limit(attribute_per_link_limit, #span_limits{attribute_per_link_limit=AttributePerLinkLimit}) ->
     AttributePerLinkLimit.
+
+cleanup_persistent_terms() ->
+    otel_utils:cleanup_persistent_terms(?MODULE).

apps/opentelemetry_api/src/opentelemetry.erl

@@ -59,7 +59,8 @@
          status/1,
          status/2,
          verify_and_set_term/3,
-         vsn_to_binary/1]).
+         vsn_to_binary/1,
+         cleanup_persistent_terms/0]).
 
 -include("opentelemetry.hrl").
 -include_lib("kernel/include/logger.hrl").
@@ -445,6 +446,9 @@ status(?OTEL_STATUS_UNSET, _Message) ->
 status(_, _) ->
     undefined.
 
+cleanup_persistent_terms() ->
+    otel_utils:cleanup_persistent_terms(?MODULE).
+
 %% internal functions
 
 -spec verify_and_set_term(module() | {module(), term()}, term(), atom()) -> boolean().

apps/opentelemetry_api/src/otel_utils.erl

@@ -21,7 +21,8 @@
          format_binary_string/2,
          format_binary_string/3,
          assert_to_binary/1,
-         unicode_to_binary/1]).
+         unicode_to_binary/1,
+         cleanup_persistent_terms/1]).
 
 -if(?OTP_RELEASE >= 24).
 format_exception(Kind, Reason, StackTrace) ->
@@ -56,3 +57,14 @@ unicode_to_binary(String) ->
         _ ->
             {error, bad_binary_conversion}
     end.
+
+-spec cleanup_persistent_terms(module()) -> ok.
+cleanup_persistent_terms(Module) ->
+    lists:foreach(
+      fun({Key, _})  ->
+              case is_tuple(Key) andalso element(1, Key) =:= Module of
+                  true -> persistent_term:erase(Key);
+                  false -> ok
+              end
+      end,
+      persistent_term:get()).

apps/opentelemetry_api_experimental/src/opentelemetry_experimental.erl

@@ -23,7 +23,8 @@
          set_default_meter/1,
          set_default_meter/2,
          get_meter/0,
-         get_meter/1]).
+         get_meter/1,
+         cleanup_persistent_terms/0]).
 
 -include_lib("kernel/include/logger.hrl").
 -include("otel_meter.hrl").
@@ -118,3 +119,6 @@ set_meter(Name, Vsn, SchemaUrl, Meter) ->
       Meter:: meter().
 set_meter(MeterProvider, Name, Vsn, SchemaUrl, Meter) ->
     opentelemetry:verify_and_set_term(Meter, ?METER_KEY(MeterProvider, {Name, Vsn, SchemaUrl}), otel_meter).
+
+cleanup_persistent_terms() ->
+    otel_utils:cleanup_persistent_terms(?MODULE).

apps/opentelemetry_experimental/src/opentelemetry_experimental_app.erl

@@ -24,6 +24,7 @@ start(_StartType, _StartArgs) ->
     {ok, Pid}.
 
 stop(_State) ->
+    _ = opentelemetry_experimental:cleanup_persistent_terms(),
     ok.
 
 %% internal functions