fix: otp28 removes the ability to cache compiled regex in macros (#904)

the compiled regex is stored in a persistent term to not have to
recompile on each tracestate creation or addition. Use of pterm
also removes the need to pass the regexes around as either part
of tracestate record or in the tracer.

Author: tsloughter

.github/workflows/erlang.yml

@@ -22,7 +22,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        otp_version: ["27.2", "26.2.5.6", "25.3.2.16"]
+        otp_version: ["28.1", "27.2", "26.2.5.6"]
         rebar3_version: ["3.24.0"]
         os: [ubuntu-24.04]
     env:
@@ -91,7 +91,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        otp_version: ["27.2"]
+        otp_version: ["28.1"]
         rebar3_version: ["3.24.0"]
         os: [ubuntu-24.04]
     steps:
@@ -119,7 +119,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        otp_version: ["27.2"]
+        otp_version: ["28.1"]
         rebar3_version: ["3.24.0"]
         os: [ubuntu-24.04]
     steps:
@@ -152,7 +152,7 @@ jobs:
     name: Test SemConv on (OTP ${{ matrix.otp_version }}) and ${{ matrix.os }}
     strategy:
       matrix:
-        otp_version: ["27.2", "25.3.2.16"]
+        otp_version: ["28.1", "26.2.5.6"]
         rebar3_version: ["3.24.0"]
         os: [ubuntu-24.04]
     defaults:

apps/opentelemetry_api/src/otel_tracestate.erl

@@ -45,42 +45,23 @@
 %% See https://www.w3.org/TR/trace-context/#tracestate-header
 %% for the limits and string requirements that make up the regexes
 -define(MAX_MEMBERS, 32).
-%% re:compile("^(([a-z][_0-9a-z\-\*\/]{0,255})|([a-z0-9][_0-9a-z-*/]{0,240}@[a-z][_0-9a-z-*/]{0,13}))$")
--define(KEY_MP, {re_pattern,3,0,0,
-                 <<69,82,67,80,59,1,0,0,16,0,0,0,1,0,0,0,255,255,255,255,
-                   255,255,255,255,0,0,0,0,0,0,3,0,0,0,64,0,0,0,0,0,0,0,
-                   0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,131,0,247,
-                   27,133,0,84,0,1,133,0,76,0,2,110,0,0,0,0,0,0,0,0,0,0,
-                   0,0,254,255,255,7,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,110,
-                   0,0,0,0,0,164,255,3,0,0,0,128,254,255,255,7,0,0,0,0,0,
-                   0,0,0,0,0,0,0,0,0,0,0,104,0,0,0,255,120,0,76,119,0,
-                   155,133,0,149,0,3,110,0,0,0,0,0,0,255,3,0,0,0,0,254,
-                   255,255,7,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,110,0,0,0,0,
-                   0,164,255,3,0,0,0,128,254,255,255,7,0,0,0,0,0,0,0,0,0,
-                   0,0,0,0,0,0,0,109,0,0,0,240,29,64,110,0,0,0,0,0,0,0,0,
-                   0,0,0,0,254,255,255,7,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-                   110,0,0,0,0,0,164,255,3,0,0,0,128,254,255,255,7,0,0,0,
-                   0,0,0,0,0,0,0,0,0,0,0,0,0,104,0,0,0,13,120,0,149,120,
-                   0,239,25,120,0,247,0>>}).
-%% re:compile("^([ -+--<>-~]{0,255}[!-+--<>-~])$")
--define(VALUE_MP, {re_pattern,1,0,0,
-                   <<69,82,67,80,152,0,0,0,16,0,0,0,1,0,0,0,255,255,255,
-                     255,255,255,255,255,0,0,0,0,0,0,1,0,0,0,64,0,0,0,0,0,
-                     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,131,0,
-                     84,27,133,0,76,0,1,110,0,0,0,0,255,239,255,223,255,
-                     255,255,255,255,255,255,127,0,0,0,0,0,0,0,0,0,0,0,0,0,
-                     0,0,0,104,0,0,0,255,110,0,0,0,0,254,239,255,223,255,
-                     255,255,255,255,255,255,127,0,0,0,0,0,0,0,0,0,0,0,0,0,
-                     0,0,0,120,0,76,25,120,0,84,0>>}).
+%%
+-define(KEY_MP, persistent_term:get({otel_tracestate, key_mp})).
+-define(VALUE_MP, persistent_term:get({otel_tracestate, value_mp})).
 
 -define(IS_STRING, (is_atom(Key) orelse is_string(Key) orelse is_binary(Key))).
 
 -spec new() -> t().
 new() ->
+    %% api had no setup so we have to ensure the persistent term for tracestate
+    %% regexes are setup each time `new' is called
+    ensure_regex_pterms(),
+
     #tracestate{members=[]}.
 
 -spec new([{unicode:latin1_chardata(), unicode:latin1_chardata()}]) -> t().
 new(List) ->
+    ensure_regex_pterms(),
     Members = [Element || {Key, Value}=Element <- List, is_valid(Key, Value)],
     #tracestate{members=Members}.
 
@@ -119,6 +100,7 @@ update(Key, Value, Tracestate=#tracestate{members=TracestateList}) ->
 decode_header(undefined) ->
     new();
 decode_header(Value) ->
+    ensure_regex_pterms(),
     #tracestate{members=parse_pairs(string:lexemes(Value, [$,]))}.
 
 -spec encode_header(t()) -> unicode:latin1_binary().
@@ -130,6 +112,18 @@ encode_header(_) ->
 
 %%
 
+ensure_regex_pterms() ->
+    try
+        _ = ?KEY_MP
+    catch
+        error:badarg ->
+            {ok, KeyMP} = re:compile("^(([a-z][_0-9a-z\-\*\/]{0,255})|([a-z0-9][_0-9a-z-*/]{0,240}@[a-z][_0-9a-z-*/]{0,13}))$"),
+            {ok, ValueMP} = re:compile("^([ -+--<>-~]{0,255}[!-+--<>-~])$"),
+
+            persistent_term:put({otel_tracestate, key_mp}, KeyMP),
+            persistent_term:put({otel_tracestate, value_mp}, ValueMP)
+    end.
+
 is_valid(Key, Value) ->
     try
         re:run(Key, ?KEY_MP, [{capture, none}]) =:= match