Move namespaces to pkg/namespaces

Signed-off-by: Derek McGowan <derek@mcg.dev>

pkg/namespaces/context_test.go

@@ -0,0 +1,71 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package namespaces
+
+import (
+	"context"
+	"testing"
+)
+
+func TestContext(t *testing.T) {
+	ctx := context.Background()
+	namespace, ok := Namespace(ctx)
+	if ok {
+		t.Fatal("namespace should not be present")
+	}
+
+	if namespace != "" {
+		t.Fatalf("namespace should not be defined: got %q", namespace)
+	}
+
+	expected := "test"
+	nctx := WithNamespace(ctx, expected)
+
+	namespace, ok = Namespace(nctx)
+	if !ok {
+		t.Fatal("expected to find a namespace")
+	}
+
+	if namespace != expected {
+		t.Fatalf("unexpected namespace: %q != %q", namespace, expected)
+	}
+}
+
+func TestNamespaceFromEnv(t *testing.T) {
+	ctx := context.Background()
+	namespace, ok := Namespace(ctx)
+	if ok {
+		t.Fatal("namespace should not be present")
+	}
+
+	if namespace != "" {
+		t.Fatalf("namespace should not be defined: got %q", namespace)
+	}
+
+	expected := "test-namespace"
+	t.Setenv(NamespaceEnvVar, expected)
+	nctx := NamespaceFromEnv(ctx)
+
+	namespace, ok = Namespace(nctx)
+	if !ok {
+		t.Fatal("expected to find a namespace")
+	}
+
+	if namespace != expected {
+		t.Fatalf("unexpected namespace: %q != %q", namespace, expected)
+	}
+}