fix(flare): fix tracer flare (#10985)

Tracer flares were failing due to AGENT_CONFIG items possibly containing
pure booleans, and not just dictionaries. Example:
```
AGENT_CONFIG=[True, {...config...}, ...]
```
This would break the flare because it would be expecting only dicts.

## 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)

(cherry picked from commit a482830)

ddtrace/internal/flare/_subscribers.py

@@ -36,7 +36,7 @@ def has_stale_flare(self) -> bool:
  return flare_age >= stale_age
  return False
 
- def _get_data_from_connector_and_exec(self):
+ def _get_data_from_connector_and_exec(self, _=None):
  if self.has_stale_flare():
  log.info(
  "Tracer flare request started at %s is stale, reverting "
@@ -67,6 +67,7 @@ def _get_data_from_connector_and_exec(self):
  str(self.current_request_start),
  )
  continue
+ log.info("Preparing tracer flare")
  if _prepare_tracer_flare(self.flare, configs):
  self.current_request_start = datetime.now()
  elif product_type == "AGENT_TASK":
@@ -75,7 +76,8 @@ def _get_data_from_connector_and_exec(self):
  if self.current_request_start is None:
  log.warning("There is no tracer flare job to complete. Skipping new request.")
  continue
+ log.info("Generating and sending tracer flare")
  if _generate_tracer_flare(self.flare, configs):
  self.current_request_start = None
  else:
- log.debug("Received unexpected product type for tracer flare: {}", product_type)
+ log.warning("Received unexpected product type for tracer flare: {}", product_type)

ddtrace/internal/flare/flare.py

@@ -98,7 +98,6 @@ def send(self, flare_send_req: FlareSendRequest):
  before sending the flare.
  """
  self.revert_configs()
-
  # We only want the flare to be sent once, even if there are
  # multiple tracer instances
  lock_path = self.flare_dir / TRACER_FLARE_LOCK

ddtrace/internal/flare/handler.py

@@ -30,6 +30,7 @@ def __init__(self, callback: Callable, flare: Flare):
 
 def _handle_tracer_flare(flare: Flare, data: dict, cleanup: bool = False):
  if cleanup:
+ log.info("Reverting tracer flare configurations and cleaning up any generated files")
  flare.revert_configs()
  flare.clean_up_files()
  return
@@ -51,7 +52,7 @@ def _handle_tracer_flare(flare: Flare, data: dict, cleanup: bool = False):
  log.warning("Received unexpected tracer flare product type: %s", product_type)
 
 
-def _prepare_tracer_flare(flare: Flare, configs: List[dict]) -> bool:
+def _prepare_tracer_flare(flare: Flare, configs: List[Any]) -> bool:
  """
  Update configurations to start sending tracer logs to a file
  to be sent in a flare later.
@@ -60,7 +61,13 @@ def _prepare_tracer_flare(flare: Flare, configs: List[dict]) -> bool:
  # AGENT_CONFIG is currently being used for multiple purposes
  # We only want to prepare for a tracer flare if the config name
  # starts with 'flare-log-level'
+ if not isinstance(c, dict):
+ log.debug("Config item is not type dict, received type %s instead. Skipping...", str(type(c)))
+ continue
  if not c.get("name", "").startswith("flare-log-level"):
+ log.debug(
+ "Config item name does not start with flare-log-level, received %s instead. Skipping...", c.get("name")
+ )
  continue
 
  flare_log_level = c.get("config", {}).get("log_level").upper()
@@ -78,7 +85,14 @@ def _generate_tracer_flare(flare: Flare, configs: List[Any]) -> bool:
  # AGENT_TASK is currently being used for multiple purposes
  # We only want to generate the tracer flare if the task_type is
  # 'tracer_flare'
- if type(c) != dict or c.get("task_type") != "tracer_flare":
+ if not isinstance(c, dict):
+ log.debug("Config item is not type dict, received type %s instead. Skipping...", str(type(c)))
+ continue
+ if c.get("task_type") != "tracer_flare":
+ log.debug(
+ "Config item does not have the expected task_type. Expected [tracer_flare], received [%s]. Skipping...",
+ c.get("task_type"),
+ )
  continue
  args = c.get("args", {})
  flare_request = FlareSendRequest(

releasenotes/notes/fix-tracer-flare-e4003d01b434267a.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+ - |
+ tracing(flare): Resolves the issue where tracer flares would not be generated if unexpected
+ types were received in the AGENT_CONFIG remote configuration product. 

tests/internal/test_tracer_flare.py

@@ -234,7 +234,7 @@ def write(self):
 
 
 class TracerFlareSubscriberTests(TestCase):
- agent_config = [{"name": "flare-log-level", "config": {"log_level": "DEBUG"}}]
+ agent_config = [False, {"name": "flare-log-level", "config": {"log_level": "DEBUG"}}]
  agent_task = [
  False,
  {