Idea: No-Code Automatic Instrumentation

[tonyo]

This discussion is to track our options and people's interest in the emerging area of automatic instrumentation without modifying the source code of the target app.

There are a few projects working in that direction already for OpenTelemetry:

1. https://github.com/keyval-dev/opentelemetry-go-instrumentation
2. https://github.com/open-telemetry/opentelemetry-go-instrumentation (looks like they're vendoring the project from 1. ?)

These projects attempt to implement this (magical) idea using eBPF, which seems to be the most promising/feasible way to do it.

Since OpenTelemetry support in sentry-go is right around the corner, it sounds possible to delegate the span creation to the OTel tooling, and then reuse our span processor (and potentially propagator) to transform the collected spans into Sentry's.

[tonyo]

Another interesting approach here, along with a great overview of how things work in other languages: https://github.com/nikolaydubina/go-instrument
The idea is to instrument at the compile time: functions that have ctx context.Context as the first argument will be enhanced with the otel code that wraps the function in a span.

[tonyo]

A pretty magical approach from Helios: https://gethelios.dev/blog/helping-go-teams-implement-opentelemetry-a-new-approach/

They're proposing to use proxy libraries that have the same interface as some popular libraries like net/http, and then at the compile time replace import “net/http” with import http “github.com/helios/go-sdk/proxy-libs/helioshttp”.