opentelemetry-instrumentation-logging: fix documented name of code attributes env var

[krrishapatel]

Description

The envvar directive in constants.py documents the code-attributes option as OTEL_PYTHON_CODE_ATTRIBUTES, but the instrumentation reads OTEL_PYTHON_LOG_CODE_ATTRIBUTES. Users who follow the published documentation set a variable that nothing reads, so code attributes silently never appear on emitted log records.

The LOG_ form is the correct one, and everything else in the package already agrees with it:

• environment_variables.py defines OTEL_PYTHON_LOG_CODE_ATTRIBUTES
• __init__.py reads environ.get(OTEL_PYTHON_LOG_CODE_ATTRIBUTES, "false")
• The prose earlier in constants.py itself refers to OTEL_PYTHON_LOG_CODE_ATTRIBUTES
• tests/test_logging.py patches OTEL_PYTHON_LOG_CODE_ATTRIBUTES

The directive at line 59 is the only place in the repository using the shorter name. It appears to be a typo introduced in #4210.

This changes documentation only. No env var handling changes, so there is no behavior change and nothing to deprecate.

Verification

I installed the package and set each name in turn, then checked whether code.* attributes appeared on an exported log record:

set OTEL_PYTHON_CODE_ATTRIBUTES=true      -> code attributes present: False  []
set OTEL_PYTHON_LOG_CODE_ATTRIBUTES=true  -> code attributes present: True   ['code.file.path', 'code.function.name', 'code.line.number']

After the fix, every envvar directive in constants.py matches a name defined in environment_variables.py, with no extras in either direction.

pytest tests/ for opentelemetry-instrumentation-logging: 71 passed.

Type of change

• This change requires a documentation update

Does This PR Require a Core Repo Change?

• Yes.
• No.

Checklist

• Followed the style guidelines of this project
• Unit tests have been added — n/a, documentation-only change; the existing test at tests/test_logging.py:405 already covers the correct variable name
• Documentation has been updated

---

Written with assistance from Claude Opus 5 (Anthropic), which located the mismatch, verified it against the installed package, and drafted this description.