`opentelemetry-bootstrap --action=requirements` should respect `OTEL_PYTHON_DISABLED_INSTRUMENTATIONS`

[idan-rahamim-lendbuzz]

What problem do you want to solve?

When building Docker images, we use opentelemetry-bootstrap --action=requirements to generate the list of instrumentor packages to install. However, this command outputs all instrumentors matching installed libraries, even those we explicitly disable at runtime via OTEL_PYTHON_DISABLED_INSTRUMENTATIONS.

This means we install packages we will never use, increasing image size and build time unnecessarily.

Example Dockerfile pattern:

ENV OTEL_PYTHON_DISABLED_INSTRUMENTATIONS="psycopg,system_metrics"

# This still outputs opentelemetry-instrumentation-psycopg and opentelemetry-instrumentation-system-metrics
RUN opentelemetry-bootstrap --action=requirements | pip install -r /dev/stdin

Describe the solution you'd like

opentelemetry-bootstrap should support filtering out disabled instrumentations:

Read OTEL_PYTHON_DISABLED_INSTRUMENTATIONS env var — if set, exclude matching instrumentors from the output. This aligns with the existing runtime behavior.

[xrmx]

I don't think it should read that environment variable, instead it could maybe take an argument with the instrumentations to exclude.

[Pranavvv3004]

Hi, I'd like to work on this. My plan is to read OTEL_PYTHON_DISABLED_INSTRUMENTATIONS in the --action=requirements path and filter out matching instrumentors before output, mirroring the existing runtime behaviour. Does this approach seem reasonable to maintainers before I open a PR?

[Pranavvv3004]

I don't think it should read that environment variable, instead it could maybe take an argument with the instrumentations to exclude.

Thanks @xrmx! So you'd prefer a --exclude argument (or similar) rather than reading the env var? Something like opentelemetry-bootstrap --action=requirements --exclude psycopg,system_metrics ? Want to confirm the flag name and format before I start.