Skip to content

Commit

Permalink
steamroll
Browse files Browse the repository at this point in the history
  • Loading branch information
@reachfh
reachfh committed Oct 22, 2023
1 parent 10a0ddb commit 0848abe
Show file tree
Hide file tree
Showing 2 changed files with 49 additions and 43 deletions.
67 changes: 32 additions & 35 deletions src/otel_propagator_xray.erl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -53,6 +53,7 @@ inject(Ctx, Carrier, CarrierSet, _Options) ->
_ -> Carrier
end.


% @doc Extract context from carrier.
-spec extract(Context, Carrier, CarrierKeysFun, CarrierGetFun, Options) ->
Context
Expand Down Expand Up @@ -81,55 +82,56 @@ parse_context(Carrier, CarrierGet) ->
_ -> throw(invalid)
end.


% @doc Decode context into span_ctx.
% Examples:
% * X-Amzn-Trace-Id: Root=1-5759e988-bd862e3fe1be46a994272793;Parent=53995c3f42cd8ad8;Sampled=0
% * X-Amzn-Trace-Id: Root=1-5759e988-bd862e3fe1be46a994272793;Sampled=1;Lineage=a87bd80c:1|68fd508a:5|c512fbe3:2
% @end
-spec decode(binary()) -> opentelemetry:span_ctx().
decode(Context) ->
% Initialize span context, setting tracing off by default
SpanCtx = otel_tracer:from_remote_span(0, 0, 0),
lists:foldl(fun decode/2, SpanCtx, string:split(Context, ";", all)).
% Initialize span context, setting tracing off by default
SpanCtx = otel_tracer:from_remote_span(0, 0, 0),
lists:foldl(fun decode/2, SpanCtx, string:split(Context, ";", all)).


-spec decode(binary(), opentelemetry:span_ctx()) -> opentelemetry:span_ctx().
decode(<<"Root=1-", Time:8/binary, "-", UniqueId:24/binary>>, SpanCtx) ->
% Save original trace ID in tracestate
% SpanCtx = set_tracestate(SpanCtx0, <<"1-", Time/binary, "-", UniqueId/binary>>),
% Parse Id and use it as trace_id
SpanCtx#span_ctx{trace_id = parse_trace_id(Time, UniqueId)};
% Save original trace ID in tracestate
% SpanCtx = set_tracestate(SpanCtx0, <<"1-", Time/binary, "-", UniqueId/binary>>),
% Parse Id and use it as trace_id
SpanCtx#span_ctx{trace_id = parse_trace_id(Time, UniqueId)};

decode(<<"Root=", _rest/binary>>, _SpanCtx) ->
throw(invalid);
decode(<<"Root=", _rest/binary>>, _SpanCtx) -> throw(invalid);

decode(<<"Parent=", ParentId:16/binary>>, SpanCtx) ->
SpanCtx#span_ctx{span_id = parse_span_id(ParentId)};

decode(<<"Parent=", _rest/binary>>, _SpanCtx) ->
throw(invalid);

decode(<<"Parent=", _rest/binary>>, _SpanCtx) -> throw(invalid);
decode(<<"Sampled=0">>, SpanCtx) -> SpanCtx#span_ctx{trace_flags = 0};
decode(<<"Sampled=1">>, SpanCtx) -> SpanCtx#span_ctx{trace_flags = 1};
decode(<<"Sampled=", _rest/binary>>, _SpanCtx) ->
throw(invalid);
decode(<<"Sampled=", _rest/binary>>, _SpanCtx) -> throw(invalid);

decode(_Value, SpanCtx) ->
% Ignore things that we don't understand, e.g. Lineage
SpanCtx.
% Ignore things that we don't understand, e.g. Lineage
SpanCtx.


% @doc Parse trace_id to integer.
% Combines time and unique id into a single big integer, following other AWS SDKs:
% * https://github.com/open-telemetry/opentelemetry-python-contrib/blob/main/propagator/opentelemetry-propagator-aws-xray/src/opentelemetry/propagators/aws/aws_xray_propagator.py
% * https://github.com/open-telemetry/opentelemetry-go-contrib/blob/main/propagators/aws/xray/propagator.go
-spec parse_trace_id(Time, UniqueId) -> non_neg_integer() when Time :: binary(),
UniqueId :: binary().
-spec parse_trace_id(Time, UniqueId) ->
non_neg_integer() when Time :: binary(), UniqueId :: binary().
parse_trace_id(Time, UniqueId) when is_binary(UniqueId) ->
case string:length(Time) =:= 8 andalso string:length(UniqueId) =:= 24 of
true ->
TraceId = iolist_to_binary([Time, UniqueId]),
string_to_integer(TraceId, 16);
_ -> throw(invalid)
end.
case string:length(Time) =:= 8 andalso string:length(UniqueId) =:= 24 of
true ->
TraceId = iolist_to_binary([Time, UniqueId]),
string_to_integer(TraceId, 16);

_ -> throw(invalid)
end.


% @doc Parse span id to integer.
parse_span_id(SpanId) when is_binary(SpanId) ->
Expand All @@ -143,12 +145,9 @@ parse_span_id(SpanId) when is_binary(SpanId) ->
% -spec set_tracestate(opentelemetry:span_ctx(), binary()) -> opentelemetry:span_ctx().
% set_tracestate(#span_ctx{tracestate = []} = SpanCtx, Value) ->
% SpanCtx#span_ctx{tracestate = [{<<"xray">>, Value}]};

% set_tracestate(#span_ctx{tracestate = Tracestate} = SpanCtx, Value) ->
% % Add new trace id to front of tracestate, removing any existing value
% SpanCtx#span_ctx{tracestate = [{<<"xray">>, Value} | lists:keydelete(<<"xray">>, 1, Tracestate)]}.


% @doc Encode span context.
-spec encode(opentelemetry:span_ctx()) -> unicode:unicode_binary().
encode(SpanCtx) ->
Expand All @@ -159,37 +158,35 @@ encode(SpanCtx) ->


-spec encode_trace_id(opentelemetry:span_ctx()) -> unicode:latin1_chardata().
encode_trace_id(#span_ctx{trace_id=TraceId}) ->
encode_trace_id(#span_ctx{trace_id = TraceId}) ->
TraceIdHex = unicode:characters_to_binary(io_lib:format("~32.16.0b", [TraceId])),
<<Time:8/binary, UniqueId:24/binary>> = TraceIdHex,
[Time, "-", UniqueId].

% encode_trace_id(#span_ctx{trace_id=TraceId, tracestate=[]}) -> generate_trace_id(TraceId);

% encode_trace_id(#span_ctx{trace_id=TraceId, tracestate=[]}) -> generate_trace_id(TraceId);
% encode_trace_id(#span_ctx{trace_id=TraceId, tracestate=Tracestate}) ->
% case lists:keyfind(<<"xray">>, 1, Tracestate) of
% false -> generate_trace_id(TraceId);
% {_, Value} -> Value
% end.


-spec encode_parent(opentelemetry:span_ctx()) -> unicode:latin1_chardata().
encode_parent(#span_ctx{span_id=0}) -> "";
encode_parent(#span_ctx{span_id=SpanId}) -> io_lib:format(";Parent=~16.16.0b", [SpanId]).
encode_parent(#span_ctx{span_id = 0}) -> "";
encode_parent(#span_ctx{span_id = SpanId}) -> io_lib:format(";Parent=~16.16.0b", [SpanId]).

-spec encode_sampled(opentelemetry:span_ctx()) -> unicode:latin1_chardata().
encode_sampled(#span_ctx{trace_flags=TraceFlags}) ->
encode_sampled(#span_ctx{trace_flags = TraceFlags}) ->
% Sampling is the default
case TraceFlags band 1 of
0 -> <<";Sampled=0">>;
_ -> <<>>
end.


% -spec generate_trace_id(opentelemetry:trace_id()) -> unicode:latin1_chardata().
% generate_trace_id(TraceId) ->
% Timestamp = opentelemetry:convert_timestamp(opentelemetry:timestamp(), second),
% ["1-", io_lib:format("~8.16.0b", [Timestamp]), io_lib:format("~24.16.0b", [TraceId])].

string_to_integer(S, Base) when is_binary(S) -> binary_to_integer(S, Base).

%% @doc Encode span context tracestate.
Expand Down
25 changes: 17 additions & 8 deletions test/otel_propagator_xray_SUITE.erl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -10,49 +10,58 @@
all() -> [fields, parse, decode].

parse() -> [{docs, "low level parsing"}].

parse(_) ->
?assertEqual(
otel_propagator_xray:string_to_integer(<<"5759e988bd862e3fe1be46a994272793">>, 16),
otel_propagator_xray:parse_trace_id(<<"5759e988">>, <<"bd862e3fe1be46a994272793">>)
),
ok.


decode() -> [{docs, "decode header"}].

decode(_) ->
SpanCtx = otel_tracer:from_remote_span(0, 0, 0),
TraceId = otel_propagator_xray:string_to_integer(<<"5759e988bd862e3fe1be46a994272793">>, 16),
SpanId = otel_propagator_xray:string_to_integer(<<"53995c3f42cd8ad8">>, 16),
?assertEqual(
SpanCtx#span_ctx{trace_id=TraceId},
SpanCtx#span_ctx{trace_id = TraceId},
otel_propagator_xray:decode(<<"Root=1-5759e988-bd862e3fe1be46a994272793">>, SpanCtx)
),
?assertEqual(
SpanCtx#span_ctx{span_id=SpanId},
SpanCtx#span_ctx{span_id = SpanId},
otel_propagator_xray:decode(<<"Parent=53995c3f42cd8ad8">>, SpanCtx)
),
?assertEqual(
SpanCtx#span_ctx{trace_flags=0},
SpanCtx#span_ctx{trace_flags = 0},
otel_propagator_xray:decode(<<"Sampled=0">>, SpanCtx)
),
?assertEqual(
SpanCtx#span_ctx{trace_flags=1},
SpanCtx#span_ctx{trace_flags = 1},
otel_propagator_xray:decode(<<"Sampled=1">>, SpanCtx)
),
?assertEqual(
SpanCtx,
otel_propagator_xray:decode(<<"Lineage=a87bd80c:1|68fd508a:5|c512fbe3:2">>, SpanCtx)
),
?assertEqual(
SpanCtx#span_ctx{trace_id=TraceId, span_id=SpanId},
otel_propagator_xray:decode(<<"Root=1-5759e988-bd862e3fe1be46a994272793;Parent=53995c3f42cd8ad8;Sampled=0">>)
SpanCtx#span_ctx{trace_id = TraceId, span_id = SpanId},
otel_propagator_xray:decode(
<<"Root=1-5759e988-bd862e3fe1be46a994272793;Parent=53995c3f42cd8ad8;Sampled=0">>
)
),
?assertEqual(
SpanCtx#span_ctx{trace_id=TraceId, trace_flags=1},
otel_propagator_xray:decode(<<"Root=1-5759e988-bd862e3fe1be46a994272793;Sampled=1;Lineage=a87bd80c:1|68fd508a:5|c512fbe3:2">>)
SpanCtx#span_ctx{trace_id = TraceId, trace_flags = 1},
otel_propagator_xray:decode(
<<
"Root=1-5759e988-bd862e3fe1be46a994272793;Sampled=1;Lineage=a87bd80c:1|68fd508a:5|c512fbe3:2"
>>
)
),
ok.


fields(_) ->
?assertEqual([<<"X-Amzn-Trace-Id">>], otel_propagator_xray:fields(foo)),
ok.

0 comments on commit 0848abe

Please sign in to comment.