Tail sampling - boolean_attribute not work for attributes from OTEL_RESOURCE_ATTRIBUTES

[gamerslouis]

Hi all,

Context

opentelemetry-operator: 0.114.1
opentelemetry-collector: 0.114.1
autoinstrumentation-python: 0.48b0

Description
I am integrating OpenTelemetry into our environment and encountered an issue while using the tail sampling processor with a "force accept" policy. Following the example provided in the tail sampling documentation, I configured the policy as follows:

- name: force-sample
  type: boolean_attribute
  boolean_attribute: { key: app.force_sample, value: true }

To test this configuration, I deployed a Python FastAPI server in a Kubernetes pod with OpenTelemetry auto-instrumentation enabled via the operator. I also set the OTEL_RESOURCE_ATTRIBUTES environment variable to:
app.force_sample=true

However, this setup did not work as expected. The OpenTelemetry instrumentation treats the value "true" as a string. Referring to the tail sampling library documentation, this results in the boolean value being interpreted as false.

To address this issue and allow the policy to work with both environment variable inputs and SDK settings, I implemented the following workaround by adding two policy rules for different value types:

- name: force-sample-str
  type: string_attribute
  string_attribute: { key: app.force_sample, values: ["true"] }
- name: force-sample
  type: boolean_attribute
  boolean_attribute: { key: app.force_sample, value: true }

Questions

• Is this the recommended approach to handle such cases, or is there a better configuration available?
• Would it be possible to improve the way OpenTelemetry instrumentation/collector handles boolean values from environment variables? Should this be considered a bug or a potential enhancement?