Merge pull request #11 from k8stopologyawareschedwg/completion-handler

tracing: add notification support

notify.go

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2023 Red Hat, Inc.
+ *
+ * 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 podfingerprint
+
+var completionSink chan<- Status
+
+// SetCompletionSink sets the process-global completion destination
+func SetCompletionSink(ch chan<- Status) {
+	completionSink = ch
+}
+
+// MarkCompleted sets a podfingerprint Status as completed.
+// When a Status is completed, it means the Status and its fingerprint is considered sealed,
+// so from now on only idempotent, non-state altering actions (like Repr(), Sign(), Check())
+// are expected to be performed. Applications which use the Tracing fingerprint can use this
+// function to clearly signal this completion point and as another option to pass the Status
+// to other subssystems.
+func MarkCompleted(st Status) error {
+	if completionSink == nil { // nothing to do
+		return nil
+	}
+	completionSink <- st.Clone()
+	return nil
+}
+
+// CleanCompletionSink should be used only in testing
+func CleanCompletionSink() {
+	completionSink = nil
+}

notify_test.go

@@ -0,0 +1,92 @@
+/*
+ * Copyright 2023 Red Hat, Inc.
+ *
+ * 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 podfingerprint
+
+import (
+	"testing"
+)
+
+func TestMarkCompleted(t *testing.T) {
+	type testCase struct {
+		name          string
+		sink          chan Status
+		status        Status
+		expectedError error
+	}
+
+	testCases := []testCase{
+		{
+			name: "no completion sink",
+			status: Status{
+				NodeName: "test-node-0",
+				Pods: []NamespacedName{
+					{
+						Namespace: "ns-1",
+						Name:      "pod-1",
+					},
+					{
+						Namespace: "ns-2",
+						Name:      "pod-2",
+					},
+					{
+						Namespace: "ns-2",
+						Name:      "pod-3",
+					},
+				},
+				FingerprintExpected: "pfp0v001807d932586d44a8a",
+				FingerprintComputed: "pfp0v001807d932586d44a8a",
+			},
+			sink: nil, // explicit
+		},
+		{
+			name: "with completion sink",
+			status: Status{
+				NodeName: "test-node-0",
+				Pods: []NamespacedName{
+					{
+						Namespace: "ns-1",
+						Name:      "pod-1",
+					},
+					{
+						Namespace: "ns-2",
+						Name:      "pod-2",
+					},
+					{
+						Namespace: "ns-2",
+						Name:      "pod-3",
+					},
+				},
+				FingerprintExpected: "pfp0v001807d932586d44a8a",
+				FingerprintComputed: "pfp0v001807d932586d44a8a",
+			},
+			sink: make(chan Status, 5), // anything > 1 is fine
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			SetCompletionSink(tc.sink)
+			err := MarkCompleted(tc.status)
+			if err != tc.expectedError {
+				t.Errorf("got error=%v expected=%v", err, tc.expectedError)
+			}
+			if tc.sink != nil && len(tc.sink) != 1 {
+				t.Errorf("unexpected data in sink: %d", len(tc.sink))
+			}
+		})
+	}
+}

tools/pfp/main.go

@@ -40,7 +40,7 @@ func main() {
 	flag.Parse()
 
 	var fp Fingerprinter
-	var st podfingerprint.Status
+	st := podfingerprint.MakeStatus("STDIN")
 	if *withTrace {
 		fp = podfingerprint.NewTracingFingerprint(0, &st)
 	} else {
@@ -59,7 +59,11 @@ func main() {
 		}
 		fp.Add(fields[0], fields[1])
 	}
-	fmt.Println(fp.Sign())
+	pfp := fp.Sign()
+	if *withTrace {
+		podfingerprint.MarkCompleted(st)
+	}
+	fmt.Println(pfp)
 
 	if *withTrace {
 		json.NewEncoder(os.Stderr).Encode(st)