fix CR

Signed-off-by: Young Bu Park <youngp@microsoft.com>

pkg/corerp/frontend/controller/applications/graph_util.go

@@ -19,6 +19,7 @@ package applications
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"net/url"
 	"sort"
 	"strings"
@@ -34,6 +35,11 @@ import (
 	"github.com/radius-project/radius/pkg/ucp/resources"
 )
 
+var (
+	// ErrInvalidSource reprents the error when the source is not a valid resource ID or URL.
+	ErrInvalidSource = errors.New("source is not a valid resource ID or URL")
+)
+
 const (
 	connectionsPath = "/properties/connections"
 	portsPath       = "/properties/container/ports"
@@ -511,12 +517,12 @@ func connectionsFromAPIData(resource generated.GenericResource, allResources []g
 // findSourceResource looks up resource id by using source string by the following steps:
 // 1. Immediately return the resource ID if the source is a valid resource ID.
 // 2. Parse the hostname from source and look up the hostname in the resource list if the source is a valid URL.
-// 3. Otherwise, return the original source string with false boolean value.
-func findSourceResource(source string, allResources []generated.GenericResource) (string, bool) {
+// 3. Otherwise, return the original source string with error.
+func findSourceResource(source string, allResources []generated.GenericResource) (string, error) {
 	// 1. Return the resource id if the source is a valid resource ID
 	id, err := resources.Parse(source)
 	if err == nil && id.IsResource() {
-		return id.String(), true
+		return id.String(), nil
 	}
 
 	// 2. Parse hostname from source and look up hostname in resource list.
@@ -529,15 +535,17 @@ func findSourceResource(source string, allResources []generated.GenericResource)
 
 	sourceURL, err := url.Parse(source)
 	if err == nil {
+		// Linear search resource name in resource list.
 		for _, resource := range allResources {
 			if to.String(resource.Name) == sourceURL.Hostname() {
-				return to.String(resource.ID), true
+				return to.String(resource.ID), nil
 			}
 		}
+		// Fall back to original source string if not found.
 	}
 
 	// 3. Return the original source string with false boolean value.
-	return orig, false
+	return orig, ErrInvalidSource
 }
 
 // providesFromAPIData is specifically to support HTTPRoute.

pkg/corerp/frontend/controller/applications/graph_util_test.go

@@ -178,45 +178,45 @@ func TestFindSourceResource(t *testing.T) {
 		resourceDataFile string
 
 		parsedSource string
-		ok           bool
+		wantErr      error
 	}{
 		{
 			name:             "valid source ID",
 			source:           "/planes/radius/local/resourcegroups/default/providers/Applications.Datastores/sqlDatabases/sql-db",
 			resourceDataFile: "graph-app-directroute-in.json",
 			parsedSource:     "/planes/radius/local/resourcegroups/default/providers/Applications.Datastores/sqlDatabases/sql-db",
-			ok:               true,
+			wantErr:          nil,
 		},
 		{
 			name:             "invalid source",
 			source:           "invalid",
 			resourceDataFile: "graph-app-directroute-in.json",
 			parsedSource:     "invalid",
-			ok:               false,
+			wantErr:          ErrInvalidSource,
 		},
 		{
 			name:             "direct route without scheme",
 			source:           "backendapp:8080",
 			resourceDataFile: "graph-app-directroute-in.json",
 			parsedSource:     "/planes/radius/local/resourcegroups/default/providers/Applications.Core/containers/backendapp",
-			ok:               true,
+			wantErr:          nil,
 		},
 		{
 			name:             "direct route with scheme",
 			source:           "http://backendapp:8080",
 			resourceDataFile: "graph-app-directroute-in.json",
 			parsedSource:     "/planes/radius/local/resourcegroups/default/providers/Applications.Core/containers/backendapp",
-			ok:               true,
+			wantErr:          nil,
 		},
 	}
 
 	for _, tc := range tests {
 		t.Run(tc.name, func(t *testing.T) {
 			resources := []generated.GenericResource{}
 			testutil.MustUnmarshalFromFile(tc.resourceDataFile, &resources)
-			parsedSource, ok := findSourceResource(tc.source, resources)
+			parsedSource, err := findSourceResource(tc.source, resources)
 			require.Equal(t, tc.parsedSource, parsedSource)
-			require.Equal(t, tc.ok, ok)
+			require.ErrorIs(t, err, tc.wantErr)
 		})
 	}
 }