Add permanent-redirect and permanent-redirect-code annotations

internal/caddy/ingress/annotations.go

@@ -3,12 +3,15 @@ package ingress
 import v1 "k8s.io/api/networking/v1"
 
 const (
-	annotationPrefix             = "caddy.ingress.kubernetes.io"
-	rewriteToAnnotation          = "rewrite-to"
-	rewriteStripPrefixAnnotation = "rewrite-strip-prefix"
-	disableSSLRedirect           = "disable-ssl-redirect"
-	backendProtocol              = "backend-protocol"
-	insecureSkipVerify           = "insecure-skip-verify"
+	annotationPrefix                = "caddy.ingress.kubernetes.io"
+	rewriteToAnnotation             = "rewrite-to"
+	rewriteStripPrefixAnnotation    = "rewrite-strip-prefix"
+	disableSSLRedirect              = "disable-ssl-redirect"
+	backendProtocol                 = "backend-protocol"
+	insecureSkipVerify              = "insecure-skip-verify"
+	permanentRedirectAnnotation     = "permanent-redirect"
+	permanentRedirectCodeAnnotation = "permanent-redirect-code"
+	temporaryRedirectAnnotation     = "temporal-redirect"
 )
 
 func getAnnotation(ing *v1.Ingress, rule string) string {

internal/caddy/ingress/redirect.go

@@ -0,0 +1,82 @@
+package ingress
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+
+	"github.com/caddyserver/caddy/v2/caddyconfig"
+	"github.com/caddyserver/caddy/v2/modules/caddyhttp"
+	"github.com/caddyserver/ingress/pkg/converter"
+)
+
+type RedirectPlugin struct{}
+
+func (p RedirectPlugin) IngressPlugin() converter.PluginInfo {
+	return converter.PluginInfo{
+		Name:     "ingress.redirect",
+		Priority: 10,
+		New:      func() converter.Plugin { return new(RedirectPlugin) },
+	}
+}
+
+// IngressHandler Converts redirect annotations to static_response handler
+func (p RedirectPlugin) IngressHandler(input converter.IngressMiddlewareInput) (*caddyhttp.Route, error) {
+	ing := input.Ingress
+
+	permanentRedir := getAnnotation(ing, permanentRedirectAnnotation)
+	temporaryRedir := getAnnotation(ing, temporaryRedirectAnnotation)
+
+	var code string = "301"
+	var redirectTo string = ""
+
+	// Don't allow both redirect annotations to be set
+	if permanentRedir != "" && temporaryRedir != "" {
+		return nil, fmt.Errorf("cannot use permanent-redirect annotation with temporal-redirect")
+	}
+
+	if permanentRedir != "" {
+		redirectCode := getAnnotation(ing, permanentRedirectCodeAnnotation)
+		if redirectCode != "" {
+			codeInt, err := strconv.Atoi(redirectCode)
+			if err != nil {
+				return nil, fmt.Errorf("not a supported redirection code type or not a valid integer: '%s'", redirectCode)
+			}
+
+			if codeInt < 300 || (codeInt > 399 && codeInt != 401) {
+				return nil, fmt.Errorf("redirection code not in the 3xx range or 401: '%v'", codeInt)
+			}
+
+			code = redirectCode
+		}
+		redirectTo = permanentRedir
+	}
+
+	if temporaryRedir != "" {
+		code = "302"
+		redirectTo = temporaryRedir
+	}
+
+	if redirectTo != "" {
+		handler := caddyconfig.JSONModuleObject(
+			caddyhttp.StaticResponse{
+				StatusCode: caddyhttp.WeakString(code),
+				Headers:    http.Header{"Location": []string{redirectTo}},
+			},
+			"handler", "static_response", nil,
+		)
+
+		input.Route.HandlersRaw = append(input.Route.HandlersRaw, handler)
+	}
+
+	return input.Route, nil
+}
+
+func init() {
+	converter.RegisterPlugin(RedirectPlugin{})
+}
+
+// Interface guards
+var (
+	_ = converter.IngressMiddleware(RedirectPlugin{})
+)

internal/caddy/ingress/redirect_test.go

@@ -0,0 +1,135 @@
+package ingress
+
+import (
+	"encoding/json"
+	"os"
+	"testing"
+
+	"github.com/caddyserver/caddy/v2/modules/caddyhttp"
+	"github.com/caddyserver/ingress/pkg/converter"
+	"github.com/stretchr/testify/assert"
+	networkingv1 "k8s.io/api/networking/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func TestRedirectConvertToCaddyConfig(t *testing.T) {
+	rp := RedirectPlugin{}
+
+	tests := []struct {
+		name               string
+		expectedConfigPath string
+		expectedError      string
+		annotations        map[string]string
+	}{
+		{
+			name:               "Check permanent redirect without any specific redirect code",
+			expectedConfigPath: "test_data/redirect_default.json",
+			annotations: map[string]string{
+				"caddy.ingress.kubernetes.io/permanent-redirect": "http://example.com",
+			},
+		},
+		{
+			name:               "Check permanent redirect with custom redirect code",
+			expectedConfigPath: "test_data/redirect_custom_code.json",
+			annotations: map[string]string{
+				"caddy.ingress.kubernetes.io/permanent-redirect":      "http://example.com",
+				"caddy.ingress.kubernetes.io/permanent-redirect-code": "308",
+			},
+		},
+		{
+			name:               "Check permanent redirect with 401 as redirect code",
+			expectedConfigPath: "test_data/redirect_401.json",
+			annotations: map[string]string{
+				"caddy.ingress.kubernetes.io/permanent-redirect":      "http://example.com",
+				"caddy.ingress.kubernetes.io/permanent-redirect-code": "401",
+			},
+		},
+		{
+			name:               "Check temporary redirect",
+			expectedConfigPath: "test_data/redirect_temporary.json",
+			annotations: map[string]string{
+				"caddy.ingress.kubernetes.io/temporal-redirect": "http://example.com",
+			},
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			input := converter.IngressMiddlewareInput{
+				Ingress: &networkingv1.Ingress{
+					ObjectMeta: metav1.ObjectMeta{
+						Annotations: test.annotations,
+					},
+				},
+				Route: &caddyhttp.Route{},
+			}
+
+			route, err := rp.IngressHandler(input)
+			assert.NoError(t, err, "failed to generate ingress route")
+
+			expectedCfg, err := os.ReadFile(test.expectedConfigPath)
+			assert.NoError(t, err, "failed to find config file for comparison")
+
+			cfgJson, err := json.Marshal(&route)
+			assert.NoError(t, err, "failed to marshal route to JSON")
+
+			assert.JSONEq(t, string(cfgJson), string(expectedCfg))
+		})
+	}
+}
+
+func TestMisconfiguredRedirectConvertToCaddyConfig(t *testing.T) {
+	rp := RedirectPlugin{}
+
+	tests := []struct {
+		name          string
+		expectedError string
+		annotations   map[string]string
+	}{
+		{
+			name: "Check permanent redirect with invalid custom redirect code",
+			annotations: map[string]string{
+				"caddy.ingress.kubernetes.io/permanent-redirect":      "http://example.com",
+				"caddy.ingress.kubernetes.io/permanent-redirect-code": "502",
+			},
+			expectedError: "redirection code not in the 3xx range or 401: '502'",
+		},
+		{
+			name: "Check permanent redirect with invalid custom redirect code string",
+			annotations: map[string]string{
+				"caddy.ingress.kubernetes.io/permanent-redirect":      "http://example.com",
+				"caddy.ingress.kubernetes.io/permanent-redirect-code": "randomstring",
+			},
+			expectedError: "not a supported redirection code type or not a valid integer: 'randomstring'",
+		},
+		{
+			name: "Check if both permanent and temporary redirection annotations are set",
+			annotations: map[string]string{
+				"caddy.ingress.kubernetes.io/permanent-redirect": "http://example.com",
+				"caddy.ingress.kubernetes.io/temporal-redirect":  "http://example2.com",
+			},
+			expectedError: "cannot use permanent-redirect annotation with temporal-redirect",
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			input := converter.IngressMiddlewareInput{
+				Ingress: &networkingv1.Ingress{
+					ObjectMeta: metav1.ObjectMeta{
+						Annotations: test.annotations,
+					},
+				},
+				Route: &caddyhttp.Route{},
+			}
+
+			route, err := rp.IngressHandler(input)
+			if assert.Error(t, err, "expected an error while generating the ingress route") {
+				assert.EqualError(t, err, test.expectedError)
+			}
+
+			cfgJson, err := json.Marshal(&route)
+			assert.NoError(t, err, "failed to marshal route to JSON")
+
+			assert.JSONEq(t, string(cfgJson), "null")
+		})
+	}
+}

internal/caddy/ingress/test_data/redirect_401.json

@@ -0,0 +1,13 @@
+{
+  "handle": [
+    {
+      "handler": "static_response",
+      "headers": {
+        "Location": [
+          "http://example.com"
+        ]
+      },
+      "status_code": 401
+    }
+  ]
+}

internal/caddy/ingress/test_data/redirect_custom_code.json

@@ -0,0 +1,13 @@
+{
+  "handle": [
+    {
+      "handler": "static_response",
+      "headers": {
+        "Location": [
+          "http://example.com"
+        ]
+      },
+      "status_code": 308
+    }
+  ]
+}

internal/caddy/ingress/test_data/redirect_default.json

@@ -0,0 +1,13 @@
+{
+  "handle": [
+    {
+      "handler": "static_response",
+      "headers": {
+        "Location": [
+          "http://example.com"
+        ]
+      },
+      "status_code": 301
+    }
+  ]
+}

internal/caddy/ingress/test_data/redirect_temporary.json

@@ -0,0 +1,13 @@
+{
+  "handle": [
+    {
+      "handler": "static_response",
+      "headers": {
+        "Location": [
+          "http://example.com"
+        ]
+      },
+      "status_code": 302
+    }
+  ]
+}