Fix prometheus rewrite metrics from counting every rule invocation, a…

…dd helm usage docs to README.md

CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.6.3] - 2024-01-26
+### Fixed
+- Fixed rewrite_success prometheus metric counting every rule invocation, instead of only rewrites
+### Changed
+- Added helm usage to the README.md
+
 ## [0.6.2] - 2023-12-06
 ### Fixed
 - Fixed ServiceMonitor templates in helm chart not rendering correctly (thanks @z0rc for the fix!)

README.md

@@ -17,9 +17,24 @@ Prerequisites
 ===
 Requires kubernetes 1.17+ and can either be installed via helm or bare manifests.
 
-Installing
+Installing with helm
 ===
-See the helm chart available in the /deploy directory.
+
+Option 1: Install from chart repository
+```shell
+helm repo add harbor-container-webhook https://indeedeng.github.io/harbor-container-webhook/
+
+helm install harbor-container-webhook harbor-container-webhook/harbor-container-webhook -n harbor-container-webhook --create-namespace 
+```
+
+Option 2: Install chart from local build
+
+Build and install the Helm chart locally after cloning the repository.
+```shell
+make helm.build
+
+helm install harbor-container-webhook ./bin/chart/harbor-container-webhook.tgz -n harbor-container-webhook --create-namespace
+```
 
 Usage
 ===

deploy/charts/harbor-container-webhook/Chart.yaml

@@ -2,8 +2,8 @@ apiVersion: v2
 name: harbor-container-webhook
 description: Webhook to configure pods with harbor proxy cache projects
 type: application
-version: 0.6.2
-appVersion: "0.6.2"
+version: 0.6.3
+appVersion: "0.6.3"
 kubeVersion: ">= 1.16.0-0"
 home: https://github.com/IndeedEng-alpha/harbor-container-webhook
 maintainers:

internal/webhook/transformer.go

@@ -184,35 +184,34 @@ func (t *ruleTransformer) auth(ctx context.Context) (authn.Authenticator, error)
 
 func (t *ruleTransformer) RewriteImage(imageRef string) (string, error) {
 	start := time.Now()
-	updatedRef, err := t.rewriteImage(imageRef)
+	rewritten, updatedRef, err := t.doRewriteImage(imageRef)
 	duration := time.Since(start)
 	if err != nil {
 		rewriteErrors.WithLabelValues(t.metricName).Inc()
-	} else {
+	} else if rewritten {
 		rewrite.WithLabelValues(t.metricName).Inc()
 		rewriteTime.WithLabelValues(t.metricName).Observe(duration.Seconds())
 	}
 	return updatedRef, err
 }
 
-func (t *ruleTransformer) rewriteImage(imageRef string) (string, error) {
+func (t *ruleTransformer) doRewriteImage(imageRef string) (rewritten bool, updatedRef string, err error) {
 	registry, err := RegistryFromImageRef(imageRef)
 	if err != nil {
-		rewriteErrors.WithLabelValues(t.metricName).Inc()
-		return "", err
+		return false, "", err
 	}
 	// shenanigans to get a fully normalized ref, e.g 'ubuntu' -> 'docker.io/library/ubuntu:latest'
 	normalizedRef, err := ReplaceRegistryInImageRef(imageRef, registry)
 	if err != nil {
-		rewriteErrors.WithLabelValues(t.metricName).Inc()
-		return "", err
+		return false, "", err
 	}
 
 	if t.findMatch(normalizedRef) && !t.anyExclusion(normalizedRef) {
-		return ReplaceRegistryInImageRef(imageRef, t.rule.Replace)
+		updatedRef, err = ReplaceRegistryInImageRef(imageRef, t.rule.Replace)
+		return true, updatedRef, err
 	}
 
-	return imageRef, nil
+	return false, imageRef, nil
 }
 
 func (t *ruleTransformer) findMatch(imageRef string) bool {