From 05499be34cc62c8da82419ae2cfc379380d2bc56 Mon Sep 17 00:00:00 2001
From: Josh Komoroske <jdkomo@gmail.com>
Date: Mon, 16 Feb 2026 16:55:07 -0500
Subject: [PATCH] feat: argocd application matcher flag

---
 cmd/command.go                          | 10 +++++
 matcher/matcher-argocd.go               | 51 +++++++++++++++++++++++++
 matcher/matcher-argocd_test.go          | 49 ++++++++++++++++++++++++
 matcher/testdata/resources.txt          |  2 +
 matcher/testdata/service.yaml           |  2 +
 matcher/testdata/subdir/deployment.yaml |  1 +
 6 files changed, 115 insertions(+)
 create mode 100644 matcher/matcher-argocd.go
 create mode 100644 matcher/matcher-argocd_test.go

diff --git a/cmd/command.go b/cmd/command.go
index 33e082a..afc0c31 100644
--- a/cmd/command.go
+++ b/cmd/command.go
@@ -69,6 +69,16 @@ func Command() *cobra.Command { //nolint:funlen,maintidx
 		"not-apiversion",
 		"exclude resources by api version")
 
+	// Define --argocd flag.
+	mf.StringSliceMatcher(matcher.NewArgoCDMatcher,
+		"argocd",
+		"include resources by ArgoCD application")
+
+	// Define --not-argocd flag.
+	mf.StringSliceMatcher(matcher.NewArgoCDMatcher,
+		"not-argocd",
+		"exclude resources by ArgoCD application")
+
 	// Define --cel flag.
 	mf.StringMatcher(matcher.NewCELMatcher,
 		"cel",
diff --git a/matcher/matcher-argocd.go b/matcher/matcher-argocd.go
new file mode 100644
index 0000000..518ec91
--- /dev/null
+++ b/matcher/matcher-argocd.go
@@ -0,0 +1,51 @@
+// Copyright Josh Komoroske. All rights reserved.
+// Use of this source code is governed by the MIT license,
+// a copy of which can be found in the LICENSE.txt file.
+// SPDX-License-Identifier: MIT
+
+package matcher
+
+import (
+	"strings"
+
+	"github.com/gobwas/glob"
+
+	"github.com/joshdk/krf/resources"
+)
+
+// NewArgoCDMatcher matches resources.Resource instances based on the ArgoCD
+// Application that the resource is being tracked by.
+func NewArgoCDMatcher(selector string) (Matcher, error) {
+	appGlob, err := glob.Compile(selector)
+	if err != nil {
+		return nil, err
+	}
+
+	m := argocdMatcher{appGlob: appGlob}
+
+	return m, nil
+}
+
+type argocdMatcher struct {
+	appGlob glob.Glob
+}
+
+func (m argocdMatcher) Matches(item resources.Resource) bool {
+	value, found := item.GetAnnotations()["argocd.argoproj.io/tracking-id"]
+	if !found {
+		return false
+	}
+
+	// The format of the tracking annotation looks like this:
+	// <application name>:<resource group>/<resource kind>:<resource namespace>/<resource name>
+	// We are interested in the application name, so we look for the location
+	// of the first ':' character and slice the string up to that point.
+	index := strings.IndexByte(value, ':')
+	if index == -1 {
+		return false
+	}
+
+	app := value[:index]
+
+	return m.appGlob.Match(app)
+}
diff --git a/matcher/matcher-argocd_test.go b/matcher/matcher-argocd_test.go
new file mode 100644
index 0000000..f838cd6
--- /dev/null
+++ b/matcher/matcher-argocd_test.go
@@ -0,0 +1,49 @@
+// Copyright Josh Komoroske. All rights reserved.
+// Use of this source code is governed by the MIT license,
+// a copy of which can be found in the LICENSE.txt file.
+// SPDX-License-Identifier: MIT
+
+package matcher_test
+
+import (
+	"testing"
+
+	"github.com/joshdk/krf/matcher"
+)
+
+func TestArgoCDMatcher(t *testing.T) {
+	t.Parallel()
+
+	testMatcher(t, []spec{
+		{
+			title:   "literal app name",
+			matcher: must(matcher.NewArgoCDMatcher("app")),
+			matches: []string{
+				"Service/my-service",
+			},
+		},
+		{
+			title:   "app name with wildcard suffix",
+			matcher: must(matcher.NewArgoCDMatcher("app*")),
+			matches: []string{
+				"Deployment/nginx-deployment",
+				"Service/my-service",
+			},
+		},
+		{
+			title:   "wildcard",
+			matcher: must(matcher.NewArgoCDMatcher("*")),
+			matches: []string{
+				"Deployment/nginx-deployment",
+				"Service/my-service",
+			},
+		},
+		{
+			title:   "wildcard with suffix",
+			matcher: must(matcher.NewArgoCDMatcher("*-dev")),
+			matches: []string{
+				"Deployment/nginx-deployment",
+			},
+		},
+	})
+}
diff --git a/matcher/testdata/resources.txt b/matcher/testdata/resources.txt
index ea3bd21..5613cdb 100644
--- a/matcher/testdata/resources.txt
+++ b/matcher/testdata/resources.txt
@@ -31,6 +31,8 @@ metadata:
     component: api
   name: my-service
   namespace: custom-app
+  annotations:
+    argocd.argoproj.io/tracking-id: app:/Service:custom-app/my-service
 spec:
   ports:
   - port: 80
diff --git a/matcher/testdata/service.yaml b/matcher/testdata/service.yaml
index 3e31bb3..38da042 100644
--- a/matcher/testdata/service.yaml
+++ b/matcher/testdata/service.yaml
@@ -6,6 +6,8 @@ metadata:
   labels:
     app: myapp
     component: api
+  annotations:
+    argocd.argoproj.io/tracking-id: app:/Service:custom-app/my-service
 spec:
   selector:
     app.kubernetes.io/name: myapp
diff --git a/matcher/testdata/subdir/deployment.yaml b/matcher/testdata/subdir/deployment.yaml
index 2eb447b..a90e3ed 100644
--- a/matcher/testdata/subdir/deployment.yaml
+++ b/matcher/testdata/subdir/deployment.yaml
@@ -8,6 +8,7 @@ metadata:
     component: proxy
   annotations:
     kubernetes.io/description: proxy
+    argocd.argoproj.io/tracking-id: app-dev:apps/Deployment:default/nginx-deployment
 spec:
   replicas: 3
   selector: