Tracing with Otel not reporting spans as expected.

[rodolfoBee]

Issue Description

With the code below, when I do a curl to the /posts URL. I expect a trace to be started, with a span for the GET /posts as the root (result in Sentry below).

But I would also expect this to have a child span that is mount-disconnected, which I can't find. I would also expect to find a child span for the DB query that is being done in Blog.list_posts(). I don't get that either.

When I do it in the browser, and actually get a websocket connection, I can find the mount-connected span. However, this have the same oddity as the non-connected case, where I don't get any child span for the find blog posts DB query.

The same tests were done exporting the opentelemetry spans to jaeger, where the user sees the expected result (info below).

Sentry stats do not show dropped spans.

Reproduction Steps

Repro app: https://github.com/allaboard-dev/oteltest

Otel span creation:

def mount(_params, _session, socket) do
span_name =
if connected?(socket) do
"mount-connected"
else
"mount-disconnected"
end

OpenTelemetry.Tracer.with_span span_name, %{the_name: span_name} do
{:ok, stream(socket, :posts, Blog.list_posts())}
end
end

Expected Behavior

The same configuration was used to send traces to jaeger, with the result:
Curl:

Browser:

Actual Behavior

The traces sent to Sentry:
Curl:

Browser:

Link to internal ticket with link to traces in Sentry

Elixir Version

1.14

SDK Version

11.0.1

Integration and Its Version

No response

Sentry Config

config :sentry,
dsn: System.get_env("SENTRY_DSN"),
environment_name: System.get_env("ENV_NAME"),
enable_source_code_context: true,
root_source_code_path: File.cwd!(),
tags: %{
env: System.get_env("ENV_NAME")
},
release: System.get_env("HEROKU_SLUG_COMMIT"),
traces_sample_rate: 1.0,
log_level: :debug

config :opentelemetry, span_processor: {Sentry.OpenTelemetry.SpanProcessor, []}
config :opentelemetry, sampler: {Sentry.OpenTelemetry.Sampler, []}

[PatrikStenmark]

I'm the one that reported this to Sentry support. Let me know if you need additional information.

[solnic]

Thanks for the report and all the details. I'll look into this!

[solnic]

@PatrikStenmark I think I got it fixed, does this look correct to you:

? 🙂