Add support for targetNamespace in Fluxtomization (#388)

Test a cluster using targetNamespace without a namespace in the
HelmRelease

Issue #387

flux_local/git_repo.py

@@ -559,7 +559,7 @@ async def build_kustomization(
 
     docs = await cmd.grep(
         f"kind=^({HELM_REPO_KIND}|{HELM_RELEASE_KIND}|{CLUSTER_POLICY_KIND})$"
-    ).objects()
+    ).objects(target_namespace=kustomization.target_namespace)
     return (
         filter(
             helm_repo_selector.predicate,

flux_local/kustomize.py

@@ -113,15 +113,21 @@ async def run(self) -> str:
         """Run the kustomize command and return the output as a string."""
         return await run_piped(self._cmds)
 
-    async def _docs(self) -> AsyncGenerator[dict[str, Any], None]:
+    async def _docs(
+        self, target_namespace: str | None = None
+    ) -> AsyncGenerator[dict[str, Any], None]:
         """Run the kustomize command and return the result documents."""
         out = await self.run()
         for doc in yaml.safe_load_all(out):
+            if target_namespace is not None:
+                doc = update_namespace(doc, target_namespace)
             yield doc
 
-    async def objects(self) -> list[dict[str, Any]]:
+    async def objects(
+        self, target_namespace: str | None = None
+    ) -> list[dict[str, Any]]:
         """Run the kustomize command and return the result cluster objects as a list."""
-        return [doc async for doc in self._docs()]
+        return [doc async for doc in self._docs(target_namespace=target_namespace)]
 
     def skip_resources(self, kinds: list[str]) -> "Kustomize":
         """Skip resources kinds of the specified types."""
@@ -283,3 +289,13 @@ def grep(expr: str, path: Path, invert: bool = False) -> Kustomize:
     else:
         args.append(str(path))
     return Kustomize([Command(args, cwd=cwd, exc=KustomizeException)])
+
+
+def update_namespace(doc: dict[str, Any], namespace: str) -> dict[str, Any]:
+    """Update the namespace of the specified document.
+
+    Will only update the namespace if the doc appears to have a metadata/name.
+    """
+    if (metadata := doc.get("metadata")) is not None and "name" in metadata:
+        doc["metadata"]["namespace"] = namespace
+    return doc

flux_local/manifest.py

@@ -287,6 +287,9 @@ class Kustomization(BaseManifest):
     source_namespace: str | None = None
     """The namespace of the sourceRef that provides this Kustomization."""
 
+    target_namespace: str | None = None
+    """The namespace to target when performing the operation."""
+
     @classmethod
     def parse_doc(cls, doc: dict[str, Any]) -> "Kustomization":
         """Parse a partial Kustomization from a kubernetes resource."""
@@ -310,6 +313,7 @@ def parse_doc(cls, doc: dict[str, Any]) -> "Kustomization":
             source_kind=source_ref.get("kind"),
             source_name=source_ref.get("name"),
             source_namespace=source_ref.get("namespace", namespace),
+            target_namespace=spec.get("targetNamespace"),
         )
 
     @property
@@ -333,6 +337,7 @@ def namespaced_name(self, sep: str = "/") -> str:
         "source_name": True,
         "source_namespace": True,
         "source_kind": True,
+        "target_namespace": True,
     }
 
 

tests/test_kustomize.py

@@ -187,3 +187,35 @@ async def test_build_flags() -> None:
     assert "Secret" in result
     assert "ConfigMap" in result
     assert result == (TESTDATA_DIR / "repo/all.golden").read_text()
+
+
+async def test_target_namespace() -> None:
+    """Test a kustomization with a target namespace."""
+    ks = kustomize.build(TESTDATA_DIR / "repo").grep("kind=ConfigMap")
+
+    result = await ks.objects()
+    assert len(result) == 1
+    config_map = result[0]
+    assert "metadata" in config_map
+    assert config_map["metadata"] == {
+        "name": "cluster-settings",
+        "namespace": "flux-system",
+        "annotations": {
+            "config.kubernetes.io/index": "0",
+            "internal.config.kubernetes.io/index": "0",
+        },
+    }
+
+    result = await ks.objects(target_namespace="configs")
+    assert len(result) == 1
+    config_map = result[0]
+    assert "metadata" in config_map
+    assert config_map["metadata"] == {
+        "name": "cluster-settings",
+        # Verify updated namespace
+        "namespace": "configs",
+        "annotations": {
+            "config.kubernetes.io/index": "0",
+            "internal.config.kubernetes.io/index": "0",
+        },
+    }

tests/testdata/cluster2/apps/networking/ingress-nginx/app/helmrelease.yaml

@@ -3,7 +3,6 @@ apiVersion: helm.toolkit.fluxcd.io/v2beta1
 kind: HelmRelease
 metadata:
   name: ingress-nginx
-  namespace: networking
 spec:
   interval: 15m
   chart:

tests/testdata/cluster2/apps/networking/ingress-nginx/app/kustomization.yaml

@@ -1,7 +1,6 @@
 ---
 apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
-namespace: networking
 resources:
   - ./helmrelease.yaml
 labels:

tests/testdata/cluster2/apps/networking/ingress-nginx/ks.yaml

@@ -23,6 +23,7 @@ metadata:
   name: cluster-apps-ingress-nginx
   namespace: flux-system
 spec:
+  targetNamespace: networking
   dependsOn:
     - name: cluster-apps-ingress-nginx-certificates
   path: ./tests/testdata/cluster2/apps/networking/ingress-nginx/app