elli instrumentation library (#69)
* elli instrumentation library * Update instrumentation/opentelemetry_elli/README.md Co-authored-by: Fred Hebert <mononcqc@ferd.ca> * Update instrumentation/opentelemetry_elli/README.md Co-authored-by: Fred Hebert <mononcqc@ferd.ca> * Update instrumentation/opentelemetry_elli/README.md Co-authored-by: Fred Hebert <mononcqc@ferd.ca> * Update instrumentation/opentelemetry_elli/README.md Co-authored-by: Fred Hebert <mononcqc@ferd.ca> * Update instrumentation/opentelemetry_elli/README.md Co-authored-by: Fred Hebert <mononcqc@ferd.ca> * Update instrumentation/opentelemetry_elli/README.md Co-authored-by: Fred Hebert <mononcqc@ferd.ca> * add note about how excluded URL env var is parsed * Update instrumentation/opentelemetry_elli/src/opentelemetry_elli.app.src Co-authored-by: Fred Hebert <mononcqc@ferd.ca> Co-authored-by: Fred Hebert <mononcqc@ferd.ca>
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Copyright 2020, Tristan Sloughter <t@crashfast.com>.
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@ -0,0 +1,94 @@
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# opentelemetry_elli
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 [](https://gitter.im/open-telemetry/opentelemetry-erlang?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
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Elli middleware for OpenTelemetry instrumentation.
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## Setup and Configuration
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``` erlang
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{deps, [opentelemetry_elli]}.
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```
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While using the `elli_middleware` callback, place `oc_elli_middelware` as the first module to be called in the list of handlers:
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``` erlang
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[{callback, elli_middleware},
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{callback_args, [{mods, [{otel_elli_middleware, []},
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{<YOUR HANDLER>, []}]}]}]
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```
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OpenTelemetry's [HTTP Semantic Conventions](https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/data-http.md#http-server) for a server details the attributes added to a Span automatically by using this middleware. One such attribute must be set in your `sys.config` under the `opentelemetry_elli` application like:
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``` erlang
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{opentelemetry_elli, [{server_name, <<"my-http-server">>}]}.
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```
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It is strongly recommended to set this environment variable so the attribute can be included:
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> http.server_name has shown great value in practice, as bogus HTTP Host headers occur often in the wild. It is strongly recommended to set http.server_name to allow associating requests with some logical server entity.
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## Use
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### Including the Middleware and setting Span names
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The middleware takes care of extracting the parent Span from the requests
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headers, both the [W3C](https://w3c.github.io/trace-context/) and [B3](https://github.com/openzipkin/b3-propagation) formats are supported.
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Because Elli has no router, there is no way to get a very descriptive Span
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name automatically. See the OpenTelemetry docs [Semantic conventions for HTTP spans](https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/data-http.md#name) for
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why you don't want to set the Span name to the raw path of the request. Thus,
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the Span has the name `"HTTP {METHOD_NAME}"`.
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The macro `update_name` from `opentelemetry_api/include/otel_tracer.hrl` allows you
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to update the name of the Span after it has started:
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``` erlang
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handle(Req, Args) ->
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handle(Req#req.path, Req, Args).
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handle([<<"hello">>, Who], Req, _Args) ->
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?update_name(<<"/hello/{who}">>),
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{ok, [], <<"Hello ", Who/binary>>}.
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```
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Attributes set by the middleware can be found in the OpenTelemetry docs [Semantic
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conventions for HTTP spans](https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/data-http.md).
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Updating the Span name is not required. Another option is to create a child Span
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with a more descriptive name, whose parent will be the Span named `"HTTP
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{METHOD_NAME}"`.
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### Excluding Paths
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Not all paths are created equal. It is likely you don't want to Trace a health
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check endpoint or `/metrics` if using Prometheus to scrape metrics. This
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library offers two ways to exclude requests from potentially creating Spans by
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filtering on the raw path in the URL.
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An application environment variable is read in on Elli start, so the following can
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be added to `sys.config` to exclude the URLs `/health` and `/metrics`:
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``` erlang
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{opentelemetry_elli, [{excluded_urls, ["/health", "/metrics"]}]}
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```
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An OS environment variable, `OTEL_ELLI_EXCLUDED_URLS`, is also read and is a
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comma separated list of paths. Note that the URLs in the variable are split with
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a simple `string:split` call, so commas are not support in any URL. No escaping
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or quoting are recognized, if a comma in a URL's path is required it should be
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percent encoded as `%2C`, this is how the URL it is compared against will appear
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in Elli anyway.
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The lists from both are merged.
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## Testing
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A Common Test suite which starts an Elli server and tests the exported Spans created by a test handle is found under `test/`. Run with:
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``` erlang
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$ rebar3 ct
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```
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{erl_opts, [debug_info]}.
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{deps, [elli,
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{opentelemetry_api, "~> 1.0"}]}.
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{project_plugins, [{rebar_covertool, "1.1.0"}]}.
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{profiles, [{test, [{erl_opts, [nowarn_export_all]},
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{deps, [{opentelemetry, "~> 1.0"}]}]}]}.
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{cover_enabled, true}.
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{cover_opts, [verbose]}.
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{cover_export_enabled, true}.
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{covertool, [{coverdata_files, ["ct.coverdata"]}]}.
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{ct_opts, [{ct_hooks, [cth_surefire]}]}.
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{"1.2.0",
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[{<<"elli">>,{pkg,<<"elli">>,<<"3.3.0">>},0},
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{<<"opentelemetry_api">>,{pkg,<<"opentelemetry_api">>,<<"1.0.2">>},0}]}.
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[
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{pkg_hash,[
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{<<"elli">>, <<"089218762A7FF3D20AE81C8E911BD0F73EE4EE0ED85454226D1FC6B4FFF3B4F6">>},
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{<<"opentelemetry_api">>, <<"91353EE40583B1D4F07D7B13ED62642ABFEC6AAA0D8A2114F07EDAFB2DF781C5">>}]},
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{pkg_hash_ext,[
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{<<"elli">>, <<"698B13B33D05661DB9FE7EFCBA41B84825A379CCE86E486CF6AFF9285BE0CCF8">>},
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{<<"opentelemetry_api">>, <<"2A8247F85C44216B883900067478D59955D11E58E5CFCA7C884CD4F203ACE3AC">>}]}
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].
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{application, opentelemetry_elli,
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[{description, "Elli middleware for tracing and stats with OpenTelemetry"},
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{vsn, "git"},
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{registered, []},
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{applications,
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[kernel,
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stdlib,
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opentelemetry_api,
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elli
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]},
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{env,[]},
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{modules, []},
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{licenses, ["Apache-2.0"]},
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{links, [{"GitHub", "https://github.com/opentelemetry-beam/opentelemetry_elli"}]}
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]}.
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|
|
@ -0,0 +1,113 @@
|
||||||
|
-module(otel_elli).
|
||||||
|
|
||||||
|
-export([start_span/1]).
|
||||||
|
|
||||||
|
-include_lib("opentelemetry_api/include/otel_tracer.hrl").
|
||||||
|
-include_lib("opentelemetry_api/include/opentelemetry.hrl").
|
||||||
|
-include_lib("elli/include/elli.hrl").
|
||||||
|
|
||||||
|
start_span(Req) ->
|
||||||
|
Method = elli_request:method(Req),
|
||||||
|
RawPath = elli_request:raw_path(Req),
|
||||||
|
|
||||||
|
%% TODO: fix in elli. it currently always returns `undefined'
|
||||||
|
%% Scheme = elli_request:scheme(Req),
|
||||||
|
|
||||||
|
%% TODO: update elli to keep the whole url
|
||||||
|
%% Url = elli_request:url(Req),
|
||||||
|
|
||||||
|
BinMethod = to_binary(Method),
|
||||||
|
SpanName = <<"HTTP ", BinMethod/binary>>,
|
||||||
|
UserAgent = elli_request:get_header(<<"User-Agent">>, Req, <<>>),
|
||||||
|
Host = case elli_request:host(Req) of
|
||||||
|
undefined ->
|
||||||
|
elli_request:get_header(<<"Host">>, Req, <<>>);
|
||||||
|
H ->
|
||||||
|
H
|
||||||
|
end,
|
||||||
|
%% TODO: attribute `http.route' should be an option to this function
|
||||||
|
{PeerIp, PeerPort} = peer_ip_and_port(Req),
|
||||||
|
{HostIp, HostPort} = host_ip_and_port(Req),
|
||||||
|
{ok, HostName} = inet:gethostname(),
|
||||||
|
|
||||||
|
Flavor = flavor(Req),
|
||||||
|
|
||||||
|
SpanCtx = ?start_span(SpanName, #{kind => ?SPAN_KIND_SERVER,
|
||||||
|
attributes => [{<<"http.target">>, RawPath},
|
||||||
|
{<<"http.host">>, Host},
|
||||||
|
%% {<<"http.url">>, Url},
|
||||||
|
%% {<<"http.scheme">>, Scheme},
|
||||||
|
{<<"http.flavor">>, Flavor},
|
||||||
|
{<<"http.user_agent">>, UserAgent},
|
||||||
|
{<<"http.method">>, BinMethod},
|
||||||
|
{<<"net.peer.ip">>, PeerIp},
|
||||||
|
{<<"net.peer.port">>, PeerPort},
|
||||||
|
{<<"net.peer.name">>, Host},
|
||||||
|
{<<"net.transport">>, <<"IP.TCP">>},
|
||||||
|
{<<"net.host.ip">>, HostIp},
|
||||||
|
{<<"net.host.port">>, HostPort},
|
||||||
|
{<<"net.host.name">>, HostName}
|
||||||
|
| optional_attributes(Req)]}),
|
||||||
|
|
||||||
|
?set_current_span(SpanCtx),
|
||||||
|
ok.
|
||||||
|
|
||||||
|
flavor(#req{version={1,1}}) ->
|
||||||
|
<<"1.1">>;
|
||||||
|
flavor(#req{version={1,0}}) ->
|
||||||
|
<<"1.0">>;
|
||||||
|
flavor(_) ->
|
||||||
|
<<>>.
|
||||||
|
|
||||||
|
to_binary(Method) when is_atom(Method) ->
|
||||||
|
atom_to_binary(Method, utf8);
|
||||||
|
to_binary(Method) ->
|
||||||
|
Method.
|
||||||
|
|
||||||
|
optional_attributes(Req) ->
|
||||||
|
lists:filtermap(fun({Attr, Fun}) ->
|
||||||
|
case Fun(Req) of
|
||||||
|
undefined ->
|
||||||
|
false;
|
||||||
|
Value ->
|
||||||
|
{true, {Attr, Value}}
|
||||||
|
end
|
||||||
|
end, [{<<"http.client_ip">>, fun client_ip/1},
|
||||||
|
{<<"http.server_name">>, fun server_name/1}]).
|
||||||
|
|
||||||
|
client_ip(Req) ->
|
||||||
|
case elli_request:get_header(<<"X-Forwarded-For">>, Req, undefined) of
|
||||||
|
undefined ->
|
||||||
|
undefined;
|
||||||
|
Ip ->
|
||||||
|
Ip
|
||||||
|
end.
|
||||||
|
|
||||||
|
server_name(_) ->
|
||||||
|
application:get_env(opentelemetry_elli, server_name, undefined).
|
||||||
|
|
||||||
|
peername({plain, Socket}) ->
|
||||||
|
inet:peername(Socket);
|
||||||
|
peername({ssl, Socket}) ->
|
||||||
|
ssl:peername(Socket).
|
||||||
|
|
||||||
|
sockname({plain, Socket}) ->
|
||||||
|
inet:sockname(Socket);
|
||||||
|
sockname({ssl, Socket}) ->
|
||||||
|
ssl:sockname(Socket).
|
||||||
|
|
||||||
|
peer_ip_and_port(#req{socket=Socket}) ->
|
||||||
|
case peername(Socket) of
|
||||||
|
{ok, {Address, Port}} ->
|
||||||
|
{list_to_binary(inet_parse:ntoa(Address)), Port};
|
||||||
|
_ ->
|
||||||
|
undefined
|
||||||
|
end.
|
||||||
|
|
||||||
|
host_ip_and_port(#req{socket=Socket}) ->
|
||||||
|
case sockname(Socket) of
|
||||||
|
{ok, {Address, Port}} ->
|
||||||
|
{list_to_binary(inet_parse:ntoa(Address)), Port};
|
||||||
|
_ ->
|
||||||
|
undefined
|
||||||
|
end.
|
||||||
|
|
@ -0,0 +1,190 @@
|
||||||
|
%%%------------------------------------------------------------------------
|
||||||
|
%% Copyright 2020, Tristan Sloughter
|
||||||
|
%% Licensed under the Apache License, Version 2.0 (the "License");
|
||||||
|
%% you may not use this file except in compliance with the License.
|
||||||
|
%% You may obtain a copy of the License at
|
||||||
|
%%
|
||||||
|
%% http://www.apache.org/licenses/LICENSE-2.0
|
||||||
|
%%
|
||||||
|
%% Unless required by applicable law or agreed to in writing, software
|
||||||
|
%% distributed under the License is distributed on an "AS IS" BASIS,
|
||||||
|
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||||
|
%% See the License for the specific language governing permissions and
|
||||||
|
%% limitations under the License.
|
||||||
|
%%
|
||||||
|
%% @doc Elli middleware for tracing requests and recording stats.
|
||||||
|
%% @end
|
||||||
|
%%%-------------------------------------------------------------------------
|
||||||
|
-module(otel_elli_middleware).
|
||||||
|
|
||||||
|
-export([preprocess/2,
|
||||||
|
handle/2,
|
||||||
|
handle_event/3]).
|
||||||
|
|
||||||
|
-include_lib("elli/include/elli.hrl").
|
||||||
|
-include_lib("opentelemetry_api/include/opentelemetry.hrl").
|
||||||
|
-include_lib("opentelemetry_api/include/otel_tracer.hrl").
|
||||||
|
|
||||||
|
-define(EXCLUDED_URLS, {?MODULE, excluded_urls}).
|
||||||
|
|
||||||
|
preprocess(Req, _) ->
|
||||||
|
%% extract trace context from headers to be used as the parent
|
||||||
|
Headers = elli_request:headers(Req),
|
||||||
|
otel_propagator_text_map:extract(Headers),
|
||||||
|
case lists:member(elli_request:raw_path(Req), persistent_term:get(?EXCLUDED_URLS, [])) of
|
||||||
|
true ->
|
||||||
|
Req;
|
||||||
|
false ->
|
||||||
|
otel_elli:start_span(Req),
|
||||||
|
Req
|
||||||
|
end.
|
||||||
|
|
||||||
|
handle(_Req, _Config) ->
|
||||||
|
ignore.
|
||||||
|
|
||||||
|
handle_event(elli_startup, _Args, _Config) ->
|
||||||
|
ExcludedUrls = collect_excluded_urls(),
|
||||||
|
|
||||||
|
%% TODO: This should really be per-server and not global across what could be multiple Elli
|
||||||
|
%% servers running within a node
|
||||||
|
persistent_term:put(?EXCLUDED_URLS, ExcludedUrls),
|
||||||
|
|
||||||
|
ok;
|
||||||
|
handle_event(request_complete, Args, Config) ->
|
||||||
|
handle_full_response(request_complete, Args, Config);
|
||||||
|
handle_event(chunk_complete, Args, Config) ->
|
||||||
|
handle_full_response(chunk_complete, Args, Config);
|
||||||
|
|
||||||
|
handle_event(request_timeout, _, _Config) ->
|
||||||
|
handle_exception(request_timeout);
|
||||||
|
handle_event(request_parse_error, [Reason], _Config) ->
|
||||||
|
handle_exception({request_parse_error, Reason});
|
||||||
|
handle_event(client_closed, [RequestPart], _Config) ->
|
||||||
|
handle_exception({client_closed, RequestPart});
|
||||||
|
handle_event(client_timeout, [RequestPart], _Config) ->
|
||||||
|
handle_exception({client_timeout, RequestPart});
|
||||||
|
handle_event(bad_request, [Reason], _Config) ->
|
||||||
|
handle_exception({bad_request, Reason});
|
||||||
|
handle_event(request_error, [_Req, Exception, Stacktrace], _Config) ->
|
||||||
|
handle_exception(error, Exception, Stacktrace);
|
||||||
|
handle_event(request_throw, [_Req, Exception, Stacktrace], _Config) ->
|
||||||
|
handle_exception(throw, Exception, Stacktrace);
|
||||||
|
handle_event(request_exit, [_Req, Exception, Stacktrace], _Config) ->
|
||||||
|
handle_exception(exit, Exception, Stacktrace);
|
||||||
|
handle_event(invalid_return, [_Req, _Unexpected], _Config) ->
|
||||||
|
%% TODO: should we include the `Unexpected' response in the attributes?
|
||||||
|
%% it could have sensitive data so should be configurable
|
||||||
|
handle_exception(invalid_return),
|
||||||
|
ok;
|
||||||
|
handle_event(_Event, _Args, _Config) ->
|
||||||
|
ok.
|
||||||
|
|
||||||
|
%%
|
||||||
|
|
||||||
|
handle_full_response(_Type, [_Req, Code, _Hs, _B, {_Timings, Sizes}], _Config) ->
|
||||||
|
maybe_set_req_body_size(Sizes),
|
||||||
|
maybe_set_resp_body_size(Sizes),
|
||||||
|
set_status(Code),
|
||||||
|
|
||||||
|
%% end the span that the user might have started
|
||||||
|
%% if there is no started span this is a noop
|
||||||
|
?end_span(),
|
||||||
|
|
||||||
|
%% `end_span' does not change the active span context in the context
|
||||||
|
%% so here the whole context must be cleared or it'd be carried over
|
||||||
|
%% to the next request that runs in the same process.
|
||||||
|
otel_ctx:clear(),
|
||||||
|
|
||||||
|
ok.
|
||||||
|
|
||||||
|
set_status(Code) ->
|
||||||
|
Status = opentelemetry:status(http_to_otel_status(Code), <<>>),
|
||||||
|
?set_status(Status),
|
||||||
|
?set_attribute(<<"http.status">>, Code).
|
||||||
|
|
||||||
|
%% Elli doesn't support any decompression so it would be up to the
|
||||||
|
%% user or their middleware/handover handler to set the attribute
|
||||||
|
%% `http.request_content_length_uncompressed'
|
||||||
|
maybe_set_req_body_size(Sizes) ->
|
||||||
|
case proplists:get_value(req_body, Sizes) of
|
||||||
|
undefined ->
|
||||||
|
ok;
|
||||||
|
ReqBodySize ->
|
||||||
|
?set_attribute(<<"http.request_content_length">>, ReqBodySize)
|
||||||
|
end.
|
||||||
|
|
||||||
|
%% Because Elli compression support is a middleware `elli_middleware_compress'
|
||||||
|
%% we are not able to set `http.request_content_length_uncompressed'.
|
||||||
|
%% So if the response body is compressed the `http.response_content_length'
|
||||||
|
%% will still be the uncompressed size.
|
||||||
|
maybe_set_resp_body_size(Sizes) ->
|
||||||
|
case proplists:get_value(chunks, Sizes) of
|
||||||
|
undefined ->
|
||||||
|
case proplists:get_value(file, Sizes) of
|
||||||
|
undefined ->
|
||||||
|
case proplists:get_value(resp_body, Sizes) of
|
||||||
|
undefined ->
|
||||||
|
ok;
|
||||||
|
RespBodySize ->
|
||||||
|
set_resp_body_size(RespBodySize)
|
||||||
|
end;
|
||||||
|
FileSize ->
|
||||||
|
set_resp_body_size(FileSize)
|
||||||
|
end;
|
||||||
|
ChunksSize ->
|
||||||
|
set_resp_body_size(ChunksSize)
|
||||||
|
end.
|
||||||
|
|
||||||
|
set_resp_body_size(Size) ->
|
||||||
|
?set_attribute(<<"http.response_content_length">>, Size).
|
||||||
|
|
||||||
|
handle_exception(Reason) ->
|
||||||
|
?set_attributes([{<<"error.message">>, format_reason(Reason)}]).
|
||||||
|
|
||||||
|
handle_exception(Class, Reason, Stacktrace) ->
|
||||||
|
?set_attributes([{<<"stacktrace">>, format_exception(Class, Reason, Stacktrace)},
|
||||||
|
{<<"error.message">>, term_to_string(Reason)}]).
|
||||||
|
|
||||||
|
format_reason(Reason) ->
|
||||||
|
term_to_string(Reason).
|
||||||
|
|
||||||
|
-if(?OTP_RELEASE >= 24).
|
||||||
|
format_exception(Class, Reason, StackTrace) ->
|
||||||
|
erl_error:format_exception(Class, Reason, StackTrace).
|
||||||
|
-else.
|
||||||
|
format_exception(Class, Reason, StackTrace) ->
|
||||||
|
io_lib:format("~p:~p ~p", [Class, Reason, StackTrace]).
|
||||||
|
-endif.
|
||||||
|
|
||||||
|
term_to_string(Term) ->
|
||||||
|
list_to_binary(io_lib:format("~p", [Term])).
|
||||||
|
|
||||||
|
http_to_otel_status(Code) when Code >= 500 ->
|
||||||
|
?OTEL_STATUS_ERROR;
|
||||||
|
http_to_otel_status(_) ->
|
||||||
|
?OTEL_STATUS_UNSET.
|
||||||
|
|
||||||
|
collect_excluded_urls() ->
|
||||||
|
%% support an app and os env var for setting paths to not trace
|
||||||
|
OSExcludePaths = case os:getenv("OTEL_ELLI_EXCLUDED_PATHS") of
|
||||||
|
false ->
|
||||||
|
[];
|
||||||
|
E ->
|
||||||
|
string:split(E, ",", all)
|
||||||
|
end,
|
||||||
|
|
||||||
|
AppExcludedPaths = application:get_env(opentelemetry_elli, excluded_paths, []),
|
||||||
|
|
||||||
|
lists:umerge(sort_paths(AppExcludedPaths),
|
||||||
|
sort_paths(OSExcludePaths)).
|
||||||
|
|
||||||
|
sort_paths(Paths) ->
|
||||||
|
lists:usort(lists:filtermap(fun path_to_binary/1, Paths)).
|
||||||
|
|
||||||
|
path_to_binary(Path) when is_list(Path) ; is_binary(Path) ->
|
||||||
|
case unicode:characters_to_binary(Path) of
|
||||||
|
{error, _, _} ->
|
||||||
|
false;
|
||||||
|
Binary ->
|
||||||
|
{true, Binary}
|
||||||
|
end.
|
||||||
|
|
@ -0,0 +1,223 @@
|
||||||
|
-module(otel_elli_SUITE).
|
||||||
|
|
||||||
|
-compile(export_all).
|
||||||
|
|
||||||
|
-include_lib("eunit/include/eunit.hrl").
|
||||||
|
-include_lib("opentelemetry_api/include/opentelemetry.hrl").
|
||||||
|
-include_lib("opentelemetry_api/include/otel_tracer.hrl").
|
||||||
|
-include_lib("opentelemetry/include/otel_span.hrl").
|
||||||
|
-include_lib("elli/include/elli.hrl").
|
||||||
|
|
||||||
|
all() ->
|
||||||
|
[{group, w3c}, {group, b3multi}, {group, b3}].
|
||||||
|
|
||||||
|
groups() ->
|
||||||
|
[{w3c, [shuffle], [successful_request_no_parent, successful_request,
|
||||||
|
error_response, excluded_paths]},
|
||||||
|
{b3, [shuffle], [successful_request_no_parent, successful_request,
|
||||||
|
error_response, excluded_paths]},
|
||||||
|
{b3multi, [shuffle], [successful_request_no_parent, successful_request,
|
||||||
|
error_response, excluded_paths]}].
|
||||||
|
|
||||||
|
init_per_suite(Config) ->
|
||||||
|
ok = application:load(opentelemetry_elli),
|
||||||
|
ok = application:load(opentelemetry),
|
||||||
|
|
||||||
|
application:set_env(opentelemetry_elli, excluded_paths, ["/hello/exclude"]),
|
||||||
|
application:set_env(opentelemetry_elli, server_name, <<"my-test-elli-server">>),
|
||||||
|
application:set_env(opentelemetry, processors, [{otel_simple_processor, #{}}]),
|
||||||
|
|
||||||
|
Config.
|
||||||
|
|
||||||
|
end_per_suite(_Config) ->
|
||||||
|
application:unload(opentelemetry),
|
||||||
|
ok.
|
||||||
|
|
||||||
|
init_per_group(Propagator, Config) ->
|
||||||
|
{ok, _} = application:ensure_all_started(opentelemetry),
|
||||||
|
|
||||||
|
Propagators = case Propagator of
|
||||||
|
w3c ->
|
||||||
|
[baggage, trace_context];
|
||||||
|
b3multi ->
|
||||||
|
[baggage, b3multi];
|
||||||
|
b3 ->
|
||||||
|
[baggage, b3]
|
||||||
|
end,
|
||||||
|
CompositePropagator = otel_propagator_text_map_composite:create(Propagators),
|
||||||
|
opentelemetry:set_text_map_propagator(CompositePropagator),
|
||||||
|
|
||||||
|
[{propagator, Propagator} | Config].
|
||||||
|
|
||||||
|
end_per_group(_, _Config)->
|
||||||
|
application:stop(opentelemetry),
|
||||||
|
ok.
|
||||||
|
|
||||||
|
init_per_testcase(_, Config) ->
|
||||||
|
elli:start_link([{name, {local, elli_test_server}},
|
||||||
|
{port, 3000},
|
||||||
|
{callback, elli_middleware},
|
||||||
|
{callback_args, [{mods, [{otel_elli_middleware, []},
|
||||||
|
{?MODULE, []}]}]}]),
|
||||||
|
|
||||||
|
otel_simple_processor:set_exporter(otel_exporter_pid, self()),
|
||||||
|
Config.
|
||||||
|
|
||||||
|
end_per_testcase(_, _Config) ->
|
||||||
|
elli:stop(elli_test_server),
|
||||||
|
ok.
|
||||||
|
|
||||||
|
excluded_paths(_Config) ->
|
||||||
|
?with_span(<<"remote-parent">>, #{},
|
||||||
|
fun(_) ->
|
||||||
|
RequestHeaders = [{binary_to_list(K), binary_to_list(V)}
|
||||||
|
|| {K, V} <- otel_propagator_text_map:inject([])],
|
||||||
|
{ok, {{_, 200, _}, _Headers, Body}} =
|
||||||
|
httpc:request(get, {"http://localhost:3000/hello/exclude",
|
||||||
|
RequestHeaders},
|
||||||
|
[], []),
|
||||||
|
?assertEqual("Hello exclude", Body)
|
||||||
|
end),
|
||||||
|
|
||||||
|
receive
|
||||||
|
{span, #span{name=Name,
|
||||||
|
parent_span_id=Parent}} when Parent =/= undefined ->
|
||||||
|
?assertEqual(<<"handler-child">>, Name),
|
||||||
|
|
||||||
|
%% then receive the remote parent
|
||||||
|
receive
|
||||||
|
{span, #span{name=ParentName,
|
||||||
|
span_id=ParentSpanId,
|
||||||
|
parent_span_id=undefined}} when ParentSpanId =:= Parent ->
|
||||||
|
?assertEqual(<<"remote-parent">>, ParentName),
|
||||||
|
|
||||||
|
%% and guarantee that the mailbox is empty, meaning no elli_middleware span
|
||||||
|
receive
|
||||||
|
_ ->
|
||||||
|
ct:fail(mailbox_not_empty)
|
||||||
|
after
|
||||||
|
0 ->
|
||||||
|
ok
|
||||||
|
end
|
||||||
|
after
|
||||||
|
5000 ->
|
||||||
|
ct:fail(timeout)
|
||||||
|
end
|
||||||
|
after
|
||||||
|
5000 ->
|
||||||
|
ct:fail(timeout)
|
||||||
|
end,
|
||||||
|
|
||||||
|
ok.
|
||||||
|
|
||||||
|
successful_request(_Config) ->
|
||||||
|
?with_span(<<"remote-parent">>, #{},
|
||||||
|
fun(_) ->
|
||||||
|
RequestHeaders = [{binary_to_list(K), binary_to_list(V)}
|
||||||
|
|| {K, V} <- otel_propagator_text_map:inject([])],
|
||||||
|
{ok, {{_, 200, _}, _Headers, Body}} =
|
||||||
|
httpc:request(get, {"http://localhost:3000/hello/otel?a=b#fragment",
|
||||||
|
RequestHeaders},
|
||||||
|
[], []),
|
||||||
|
?assertEqual("Hello otel", Body)
|
||||||
|
end),
|
||||||
|
|
||||||
|
receive
|
||||||
|
{span, #span{name = <<"/hello/{who}">>,
|
||||||
|
parent_span_id=Parent,
|
||||||
|
attributes=Attributes,
|
||||||
|
events=_TimeEvents}} when Parent =/= undefined ->
|
||||||
|
?assertMatch(#{<<"http.server_name">> := <<"my-test-elli-server">>,
|
||||||
|
<<"http.target">> := <<"/hello/otel?a=b">>,
|
||||||
|
<<"http.host">> := <<"localhost:3000">>,
|
||||||
|
%% removed until updates to elli allow it
|
||||||
|
%% <<"http.url">> := <<"http://localhost:3000/hello/otel?a=b">>,
|
||||||
|
%% scheme is removed until fixed in elli
|
||||||
|
%% <<"http.scheme">> := <<"http">>,
|
||||||
|
<<"http.status">> := 200,
|
||||||
|
%% <<"http.user_agent">> := <<>>,
|
||||||
|
<<"http.method">> := <<"GET">>,
|
||||||
|
<<"net.host.port">> := 3000}, otel_attributes:map(Attributes)),
|
||||||
|
|
||||||
|
%% then receive the remote parent
|
||||||
|
receive
|
||||||
|
{span, #span{name=ParentName,
|
||||||
|
span_id=ParentSpanId,
|
||||||
|
parent_span_id=undefined}} when ParentSpanId =:= Parent ->
|
||||||
|
?assertEqual(<<"remote-parent">>, ParentName)
|
||||||
|
after
|
||||||
|
5000 ->
|
||||||
|
ct:fail(timeout)
|
||||||
|
end
|
||||||
|
after
|
||||||
|
5000 ->
|
||||||
|
ct:fail(timeout)
|
||||||
|
end,
|
||||||
|
|
||||||
|
ok.
|
||||||
|
|
||||||
|
successful_request_no_parent(_Config) ->
|
||||||
|
{ok, {{_, 200, _}, _Headers, Body}} = httpc:request("http://localhost:3000/hello/otel?a=b#fragment"),
|
||||||
|
?assertEqual("Hello otel", Body),
|
||||||
|
|
||||||
|
receive
|
||||||
|
{span, #span{name = <<"/hello/{who}">>,
|
||||||
|
parent_span_id=Parent,
|
||||||
|
attributes=Attributes,
|
||||||
|
events=_TimeEvents}} ->
|
||||||
|
?assertEqual(undefined, Parent),
|
||||||
|
?assertMatch(#{<<"http.server_name">> := <<"my-test-elli-server">>,
|
||||||
|
<<"http.target">> := <<"/hello/otel?a=b">>,
|
||||||
|
<<"http.host">> := <<"localhost:3000">>,
|
||||||
|
%% scheme is removed until fixed in elli
|
||||||
|
%% <<"http.scheme">> := <<"http">>,
|
||||||
|
<<"http.status">> := 200,
|
||||||
|
<<"http.user_agent">> := <<>>,
|
||||||
|
<<"http.method">> := <<"GET">>,
|
||||||
|
<<"net.host.port">> := 3000}, otel_attributes:map(Attributes))
|
||||||
|
after
|
||||||
|
5000 ->
|
||||||
|
ct:fail(timeout)
|
||||||
|
end,
|
||||||
|
ok.
|
||||||
|
|
||||||
|
error_response(_Config) ->
|
||||||
|
{ok, {{_, 500, _}, _Headers, _Body}} = httpc:request("http://localhost:3000/error?a=b#fragment"),
|
||||||
|
|
||||||
|
receive
|
||||||
|
{span, #span{name=Name,
|
||||||
|
parent_span_id=Parent,
|
||||||
|
attributes=Attributes}} ->
|
||||||
|
?assertEqual(undefined, Parent),
|
||||||
|
?assertEqual(<<"HTTP GET">>, Name),
|
||||||
|
?assertMatch(#{<<"http.server_name">> := <<"my-test-elli-server">>,
|
||||||
|
<<"http.target">> := <<"/error?a=b">>,
|
||||||
|
<<"http.host">> := <<"localhost:3000">>,
|
||||||
|
<<"http.status">> := 500,
|
||||||
|
<<"http.user_agent">> := <<>>,
|
||||||
|
<<"error.message">> := <<"all_hell">>,
|
||||||
|
<<"http.method">> := <<"GET">>}, otel_attributes:map(Attributes))
|
||||||
|
after
|
||||||
|
5000 ->
|
||||||
|
ct:fail(timeout)
|
||||||
|
end,
|
||||||
|
ok.
|
||||||
|
%%
|
||||||
|
|
||||||
|
handle(Req, Args) ->
|
||||||
|
handle(Req#req.path, Req, Args).
|
||||||
|
|
||||||
|
handle([<<"hello">>, Who], _Req, _Args) ->
|
||||||
|
?update_name(<<"/hello/{who}">>),
|
||||||
|
|
||||||
|
?with_span(<<"handler-child">>, #{},
|
||||||
|
fun(_) ->
|
||||||
|
ok
|
||||||
|
end),
|
||||||
|
|
||||||
|
{ok, [], <<"Hello ", Who/binary>>};
|
||||||
|
handle([<<"error">>], _Req, _Args) ->
|
||||||
|
throw(all_hell).
|
||||||
|
|
||||||
|
handle_event(_Event, _Data, _Args) ->
|
||||||
|
ok.
|
||||||
Loading…
Reference in New Issue