fix(asm): fix config in api_manager (#7678)

- fix config use in api_manager for api security.
- ensure api security global callback is only called once in all
supported frameworks.

No release note necessary as the feature is private and experimental for
now.

This will be covered later by system-tests

## Checklist

- [x] Change(s) are motivated and described in the PR description.
- [x] Testing strategy is described if automated tests are not included
in the PR.
- [x] Risk is outlined (performance impact, potential for breakage,
maintainability, etc).
- [x] Change is maintainable (easy to change, telemetry, documentation).
- [x] [Library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
are followed. If no release note is required, add label
`changelog/no-changelog`.
- [x] Documentation is included (in-code, generated user docs, [public
corp docs](https://github.com/DataDog/documentation/)).
- [x] Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist

- [ ] Title is accurate.
- [ ] No unnecessary changes are introduced.
- [ ] Description motivates each change.
- [ ] Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes unless absolutely necessary.
- [ ] Testing strategy adequately addresses listed risk(s).
- [ ] Change is maintainable (easy to change, telemetry, documentation).
- [ ] Release note makes sense to a user of the library.
- [ ] Reviewer has explicitly 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)
- [ ] If this PR touches code that signs or publishes builds or
packages, or handles credentials of any kind, I've requested a review
from `@DataDog/security-design-and-guidance`.
- [ ] This PR doesn't touch any of that.

---------

Co-authored-by: Alberto Vara <alberto.vara@datadoghq.com>
Co-authored-by: Eric Navarro <eric.navarro@datadoghq.com>
Co-authored-by: Romain Komorn <136473744+romainkomorndatadog@users.noreply.github.com>
Co-authored-by: Brett Langdon <brett.langdon@datadoghq.com>

ddtrace/appsec/_api_security/api_manager.py

@@ -4,7 +4,6 @@
 import sys
 from typing import TYPE_CHECKING
 
-from ddtrace import config
 from ddtrace._tracing._limits import MAX_SPAN_META_VALUE_LEN
 from ddtrace.appsec import _processor as appsec_processor
 from ddtrace.appsec._asm_request_context import add_context_callback
@@ -15,6 +14,7 @@
 from ddtrace.internal.logger import get_logger
 from ddtrace.internal.metrics import Metrics
 from ddtrace.internal.service import Service
+from ddtrace.settings.asm import config as asm_config
 
 
 if TYPE_CHECKING:
@@ -90,7 +90,7 @@ def _start_service(self):
     def _should_collect_schema(self, env):
         method = env.waf_addresses.get(SPAN_DATA_NAMES.REQUEST_METHOD)
         route = env.waf_addresses.get(SPAN_DATA_NAMES.REQUEST_ROUTE)
-        sample_rate = config._api_security_sample_rate
+        sample_rate = asm_config._api_security_sample_rate
         # Framework is not fully supported
         if not method or not route:
             log.debug("unsupported groupkey for api security [method %s] [route %s]", bool(method), bool(route))

ddtrace/appsec/_asm_request_context.py

@@ -53,6 +53,7 @@ def __init__(self, active: bool = False):
         self.callbacks: Dict[str, Any] = {}
         self.telemetry: Dict[str, Any] = {}
         self.addresses_sent: Set[str] = set()
+        self.must_call_globals: bool = True
 
 
 def _get_asm_context() -> ASM_Environment:
@@ -96,10 +97,11 @@ def unregister(span: Span) -> None:
     env = _get_asm_context()
     if env.span_asm_context is not None and env.span is span:
         env.span_asm_context.__exit__(None, None, None)
-    elif env.span is span:
+    elif env.span is span and env.must_call_globals:
         # needed for api security flushing information before end of the span
         for function in GLOBAL_CALLBACKS.get(_CONTEXT_CALL, []):
             function(env)
+        env.must_call_globals = False
 
 
 class _DataHandler:
@@ -125,7 +127,8 @@ def __init__(self):
     def finalise(self):
         if self.active:
             env = self.execution_context.get_item("asm_env")
-            callbacks = GLOBAL_CALLBACKS.get(_CONTEXT_CALL, [])
+            callbacks = GLOBAL_CALLBACKS.get(_CONTEXT_CALL, []) if env.must_call_globals else []
+            env.must_call_globals = False
             if env is not None and env.callbacks is not None and env.callbacks.get(_CONTEXT_CALL):
                 callbacks += env.callbacks.get(_CONTEXT_CALL)
             if callbacks: