From eeeb43733d8e798d63c064a3b789630aa3640f38 Mon Sep 17 00:00:00 2001
From: Pavan Raga <pavan.raga@prudential.com.sg>
Date: Mon, 25 Jan 2021 20:48:40 +0800
Subject: [PATCH 1/2] added EXCLUDE_NAMESPACE functionality

---
 README.md |  3 ++-
 main.go   | 44 +++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index bb16260..221573a 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,8 @@ Configuration is done completely via environment variables.
 | -- | -- |
 | `SENTRY_DSN` | **Required** DSN for a Sentry project. |
 | `SENTRY_ENVIRONMENT` | Environment for Sentry issues. If not set the namespace is used as environment. |
-| `NAMESPACE` | Comma separated set of namespaces to minitor. If not set all namespaces are monitored (as far as permissions allow) |
+| `NAMESPACE` | Comma separated set of namespaces to monitor. If not set all namespaces are monitored (as far as permissions allow) |
+| `EXCLUDE_NAMESPACE` | Comma separated set of namespaces to not monitor. If `NAMESPACE` is also set, namespaces are excluded from that else from all namespaces|
 
 ## Issue grouping
 
diff --git a/main.go b/main.go
index 1fe3cbb..b875941 100644
--- a/main.go
+++ b/main.go
@@ -67,11 +67,31 @@ func main() {
 		defaultEnvironment: os.Getenv("SENTRY_ENVIRONMENT"),
 	}
 
-	namespace := os.Getenv("NAMESPACE")
-	if namespace == "" {
-		app.namespaces = []string{v1.NamespaceAll}
-	} else {
-		app.namespaces = strings.Split(namespace, ",")
+	inNamespace := strings.Split(os.Getenv("NAMESPACE"), ",")
+	exNamespace := strings.Split(os.Getenv("EXCLUDE_NAMESPACE"), ",")
+	allNamespace := []string{v1.NamespaceAll}
+
+	switch inNamespace {
+	// include all namespaces
+	case nil:
+		switch exNamespace {
+		// exclude nothing
+		case nil:
+			app.namespaces = allNamespace
+		// exclude some
+		default:
+			app.namespaces = difference(allNamespace, exNamespace)
+		}
+	// include only some namespaces
+	default:
+		switch exNamespace {
+		// include some, exclude nothing
+		case nil:
+			app.namespaces = inNamespace
+		// include some, exclude some from it
+		default:
+			app.namespaces = difference(inNamespace, exNamespace)
+		}
 	}
 
 	stopSignal, err := app.Run()
@@ -108,3 +128,17 @@ func createKubernetesClient(configFile string) (client *kubernetes.Clientset, er
 	}
 	return kubernetes.NewForConfig(config)
 }
+
+func difference(allNamespace, exNamespace []string) []string {
+	mapdiff := make(map[string]struct{}, len(exNamespace))
+	for _, ns := range exNamespace {
+		mapdiff[ns] = struct{}{}
+	}
+	var diff []string
+	for _, ns := range allNamespace {
+		if _, found := mapdiff[ns]; !found {
+			diff = append(diff, ns)
+		}
+	}
+	return diff
+}

From 791f25ca4c572fdd50a1838dfd53ca64ac8f4fe3 Mon Sep 17 00:00:00 2001
From: Pavan Raga <pavan.raga@prudential.com.sg>
Date: Mon, 1 Feb 2021 19:56:51 +0800
Subject: [PATCH 2/2] updated with logic correction

---
 main.go | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/main.go b/main.go
index b875941..de149c3 100644
--- a/main.go
+++ b/main.go
@@ -71,12 +71,12 @@ func main() {
 	exNamespace := strings.Split(os.Getenv("EXCLUDE_NAMESPACE"), ",")
 	allNamespace := []string{v1.NamespaceAll}
 
-	switch inNamespace {
+	switch len(inNamespace) {
 	// include all namespaces
-	case nil:
-		switch exNamespace {
+	case 0:
+		switch len(exNamespace) {
 		// exclude nothing
-		case nil:
+		case 0:
 			app.namespaces = allNamespace
 		// exclude some
 		default:
@@ -84,9 +84,9 @@ func main() {
 		}
 	// include only some namespaces
 	default:
-		switch exNamespace {
+		switch len(exNamespace) {
 		// include some, exclude nothing
-		case nil:
+		case 0:
 			app.namespaces = inNamespace
 		// include some, exclude some from it
 		default: