16419 FIX Support IPv6/IPv4 Dual Stack

For Kubernetes clusters running a IPv6/IPv4 dual stack, the collectors would display the following
error:

C+:
File "/home/solo/git/checkmk_kube_agent/.venv/lib/python3.10/site-packages/requests/sessions.py", line 794, in get_adapter
    raise InvalidSchema(f"No connection adapters were found for {url!r}")
requests.exceptions.InvalidSchema: No connection adapters were found for '::'
C-:

This has been fixed.

Change-Id: I2e09841bb307393115caa21be7b277c3a392ab22

.werks/16419

@@ -0,0 +1,22 @@
+Title: Support IPv6/IPv4 Dual Stack
+Class: fix
+Compatible: compat
+Component: cluster-collector
+Date: 1712156163
+Knowledge: doc
+Level: 1
+Version: 2.0.0-alpha.1
+
+For Kubernetes clusters running a IPv6/IPv4 dual stack, the node collectors would display the
+following error:
+
+C+:
+File "/home/solo/git/checkmk_kube_agent/.venv/lib/python3.10/site-packages/requests/sessions.py", line 794, in get_adapter
+    raise InvalidSchema(f"No connection adapters were found for {url!r}")
+requests.exceptions.InvalidSchema: No connection adapters were found for '::'
+C-:
+
+This has been fixed.
+
+Moreover, the cluster collector was hardcoded to bind to a socket with address family AF_INET. This
+is now configurable with the values.yaml file via the option '.clusterCollector.address'.

src/checkmk_kube_agent/api.py

@@ -146,7 +146,7 @@ def _check_token_review_content(
     return None
 
 
-def _join_host_port(host: str, port: str) -> str:  # pragma: no cover
+def _join_host_port(host: str, port: str) -> str:
     # reference implementation
     # https://cs.opensource.google/go/go/+/refs/tags/go1.22.1:src/net/ipsock.go;l=235
     if ":" in host:

tests/unit/test_api.py

@@ -25,6 +25,7 @@
     StandaloneApplication,
     TokenError,
     _init_app_state,
+    _join_host_port,
     _raise_from_token_error,
     app,
     authenticate,
@@ -841,3 +842,10 @@ def test_send_metadata(
             machine_sections_collection.metadata,
         ],
     )
+
+
+def test_join_host_port() -> None:
+    """Test IpV4 and IpV6."""
+
+    assert _join_host_port("127.0.0.1", "8000") == "127.0.0.1:8000"
+    assert _join_host_port("::", "8000") == "[::]:8000"