fix(docs): update log injection support (#14031)

With ddtrace v3.10.0 `log injection` is enabled by default for
structured loggers. This PR updates documentation and adds a more
release note.

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [ ] Reviewer has checked that all the criteria below are met
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

---------

Co-authored-by: Brett Langdon <[email protected]>
(cherry picked from commit 5494169)

Author: 2 people

ddtrace/contrib/_logging.py

@@ -5,7 +5,7 @@
 attributes to the log record.
 
 2. Updating the log formatter used by the application. In order to inject
-tracing information into a log the formatter must be updated to include the
+tracing information using the log the formatter must be updated to include the
 tracing attributes from the log record.
 
 
@@ -15,22 +15,20 @@
 Patch ``logging``
 ~~~~~~~~~~~~~~~~~
 
-There are a few ways to tell ddtrace to patch the ``logging`` module:
-
-1. If using :ref:`ddtrace-run<ddtracerun>`, you can set the environment variable ``DD_LOGS_INJECTION=true``.
-
-2. Use :func:`patch()<ddtrace.patch>` to manually enable the integration::
-
-    from ddtrace import patch
-    patch(logging=True)
-
-3. (beta) Set ``log_injection_enabled`` at runtime via the Datadog UI.
+Datadog support for built-in logging is enabled by default when you either: run your application
+with the ddtrace-run command, or Import ddtrace.auto in your code. If you are using the ddtrace
+library directly, you can enable logging support by calling: ``ddtrace.patch(logging=True)``.
+Note: Directly enabling integrations via ddtrace.patch(...) is not recommended.
 
 
 Update Log Format
 ~~~~~~~~~~~~~~~~~
 
-Make sure that your log format exactly matches the following::
+Make sure that your log format supports the following attributes: ``dd.trace_id``, ``dd.span_id``,
+``dd.service``, ``dd.env``, ``dd.version``. These values will be automatically added to
+the log record by the ``ddtrace`` library.
+
+Example::
 
     import logging
     from ddtrace.trace import tracer

docs/configuration.rst

@@ -749,9 +749,16 @@ Logs
 .. ddtrace-configuration-options::
 
    DD_LOGS_INJECTION:
-     type: string
-     default: structured
-     description: Enables :ref:`Logs Injection`. Supported values are ``false``, ``true``, and ``structured``.
+     type: Boolean
+     default: True
+     description: Enables :ref:`Logs Injection`. Supported values are ``false``, and ``true``.
+     version_added:
+       v0.51.0: |
+         Added support for correlating traces to log using the builtin logger. This feature was disabled by default.
+       v3.10.0: |
+         The default value was changed to ``true``. This means that the tracer will inject trace context into logs when ``ddtrace-run`` or ``import ddtrace.auto`` is used.
+         To disable this behavior, set ``DD_LOGS_INJECTION=false``.
+       
 
    DD_TRACE_DEBUG:
      type: Boolean

releasenotes/notes/feat-log-injection-enabled-by-default-395259b0419c7a5f.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    logging: Automatic injection of trace attributes into logs is now enabled for the standard logging library when using
+    either ``ddtrace-run`` or ``import ddtrace.auto``. To disable this feature, set the environment variable ``DD_LOGS_INJECTION`` to `False`.