fix(runtime): add support for PCF containers (backport #4405) (#4420)

This is an automatic backport of pull request #4405 done by [Mergify](https://mergify.com).


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Author: mergify[bot]

ddtrace/internal/runtime/container.py

@@ -23,7 +23,11 @@ class CGroupInfo(object):
     controllers = attr.ib(default=None)
     pod_id = attr.ib(default=None)
 
-    UUID_SOURCE_PATTERN = r"[0-9a-f]{8}[-_][0-9a-f]{4}[-_][0-9a-f]{4}[-_][0-9a-f]{4}[-_][0-9a-f]{12}"
+    # The second part is the PCF/Garden regexp. We currently assume no suffix ($) to avoid matching pod UIDs
+    # See https://github.com/DataDog/datadog-agent/blob/7.40.x/pkg/util/cgroups/reader.go#L50
+    UUID_SOURCE_PATTERN = (
+        r"[0-9a-f]{8}[-_][0-9a-f]{4}[-_][0-9a-f]{4}[-_][0-9a-f]{4}[-_][0-9a-f]{12}|([0-9a-f]{8}(-[0-9a-f]{4}){4}$)"
+    )
     CONTAINER_SOURCE_PATTERN = r"[0-9a-f]{64}"
     TASK_PATTERN = r"[0-9a-f]{32}-\d+"
 

releasenotes/notes/PCF-container-UUID-0f65eed47e42f4ad.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    CGroup file parsing was fixed to correctly parse container UUID for PCF containers.

tests/tracer/runtime/test_container.py

@@ -70,6 +70,18 @@ def test_cgroup_info_init():
                 pod_id=None,
             ),
         ),
+        # Valid, PCF
+        (
+            "10:freezer:/garden/6f265890-5165-7fab-6b52-18d1",
+            CGroupInfo(
+                id="10",
+                groups="freezer",
+                controllers=["freezer"],
+                path="/garden/6f265890-5165-7fab-6b52-18d1",
+                container_id="6f265890-5165-7fab-6b52-18d1",
+                pod_id=None,
+            ),
+        ),
         # Invalid container_ids
         (
             # One character too short
@@ -240,6 +252,24 @@ def test_cgroup_info_from_line(line, expected_info):
             """,
             "34dc0b5e626f2c5c4c5170e34b10e765-1234567890",
         ),
+        # PCF file
+        (
+            """
+12:rdma:/
+11:net_cls,net_prio:/garden/6f265890-5165-7fab-6b52-18d1
+10:freezer:/garden/6f265890-5165-7fab-6b52-18d1
+9:devices:/system.slice/garden.service/garden/6f265890-5165-7fab-6b52-18d1
+8:blkio:/system.slice/garden.service/garden/6f265890-5165-7fab-6b52-18d1
+7:pids:/system.slice/garden.service/garden/6f265890-5165-7fab-6b52-18d1
+6:memory:/system.slice/garden.service/garden/6f265890-5165-7fab-6b52-18d1
+5:cpuset:/garden/6f265890-5165-7fab-6b52-18d1
+4:cpu,cpuacct:/system.slice/garden.service/garden/6f265890-5165-7fab-6b52-18d1
+3:perf_event:/garden/6f265890-5165-7fab-6b52-18d1
+2:hugetlb:/garden/6f265890-5165-7fab-6b52-18d1
+1:name=systemd:/system.slice/garden.service/garden/6f265890-5165-7fab-6b52-18d1
+            """,
+            "6f265890-5165-7fab-6b52-18d1",
+        ),
         # Linux non-containerized file
         (
             """