Add support for kustomization resources (#2416) (#2420)

As of version 2.1, Kustomize has deprecated bases in favor of combining
the functionality with resources by enforcing merge order based on
resource array order. This means resources now may act as bases do today
instead of being simply files - they may point to kustomiziations
(directories with a kustomization config in the root) or even to remote
locations. The code to generate the list of dependencies for file
watching has been updated accordingly.

pkg/skaffold/deploy/kustomize.go

@@ -167,23 +167,30 @@ func dependenciesForKustomization(dir string) ([]string, error) {
 		return nil, err
 	}
 
-	for _, base := range content.Bases {
+	deps = append(deps, path)
+
+	candidates := append(content.Bases, content.Resources...)
+
+	for _, candidate := range candidates {
 		// If the file  doesn't exist locally, we can assume it's a remote file and
 		// skip it, since we can't monitor remote files. Kustomize itself will
 		// handle invalid/missing files.
-		if !fileExistsLocally(base, dir) {
+		local, mode := pathExistsLocally(candidate, dir)
+		if !local {
 			continue
 		}
-		baseDeps, err := dependenciesForKustomization(filepath.Join(dir, base))
-		if err != nil {
-			return nil, err
-		}
 
-		deps = append(deps, baseDeps...)
+		if mode.IsDir() {
+			candidateDeps, err := dependenciesForKustomization(filepath.Join(dir, candidate))
+			if err != nil {
+				return nil, err
+			}
+			deps = append(deps, candidateDeps...)
+		} else {
+			deps = append(deps, filepath.Join(dir, candidate))
+		}
 	}
 
-	deps = append(deps, path)
-	deps = append(deps, joinPaths(dir, content.Resources)...)
 	deps = append(deps, joinPaths(dir, content.Patches)...)
 	deps = append(deps, joinPaths(dir, content.PatchesStrategicMerge)...)
 	deps = append(deps, joinPaths(dir, content.CRDs)...)
@@ -210,15 +217,15 @@ func joinPaths(root string, paths []string) []string {
 	return list
 }
 
-func fileExistsLocally(filename string, workingDir string) bool {
+func pathExistsLocally(filename string, workingDir string) (bool, os.FileMode) {
 	path := filename
 	if !filepath.IsAbs(filename) {
 		path = filepath.Join(workingDir, filename)
 	}
-	if _, err := os.Stat(path); err == nil {
-		return true
+	if f, err := os.Stat(path); err == nil {
+		return true, f.Mode()
 	}
-	return false
+	return false, 0
 }
 
 // Dependencies lists all the files that can change what needs to be deployed.

pkg/skaffold/deploy/kustomize_test.go

@@ -167,6 +167,10 @@ func TestDependenciesForKustomization(t *testing.T) {
 			description: "resources",
 			yaml:        `resources: [pod1.yaml, path/pod2.yaml]`,
 			expected:    []string{"kustomization.yaml", "pod1.yaml", "path/pod2.yaml"},
+			createFiles: map[string]string{
+				"pod1.yaml":      "",
+				"path/pod2.yaml": "",
+			},
 		},
 		{
 			description: "paches",
@@ -207,16 +211,45 @@ func TestDependenciesForKustomization(t *testing.T) {
 		{
 			description: "base exists locally",
 			yaml:        `bases: [base]`,
-			expected:    []string{"base/kustomization.yaml", "base/app.yaml", "kustomization.yaml"},
+			expected:    []string{"kustomization.yaml", "base/kustomization.yaml", "base/app.yaml"},
 			createFiles: map[string]string{
 				"base/kustomization.yaml": `resources: [app.yaml]`,
+				"base/app.yaml":           "",
 			},
 		},
 		{
 			description: "missing base locally",
 			yaml:        `bases: [missing-or-remote-base]`,
 			expected:    []string{"kustomization.yaml"},
 		},
+		{
+			description: "local kustomization resource",
+			yaml:        `resources: [app.yaml, base]`,
+			expected:    []string{"kustomization.yaml", "app.yaml", "base/kustomization.yaml", "base/app.yaml"},
+			createFiles: map[string]string{
+				"app.yaml":                "",
+				"base/kustomization.yaml": `resources: [app.yaml]`,
+				"base/app.yaml":           "",
+			},
+		},
+		{
+			description: "missing local kustomization resource",
+			yaml:        `resources: [app.yaml, missing-or-remote-base]`,
+			expected:    []string{"kustomization.yaml", "app.yaml"},
+			createFiles: map[string]string{
+				"app.yaml": "",
+			},
+		},
+		{
+			description: "mixed resource types",
+			yaml:        `resources: [app.yaml, missing-or-remote-base, base]`,
+			expected:    []string{"kustomization.yaml", "app.yaml", "base/kustomization.yaml", "base/app.yaml"},
+			createFiles: map[string]string{
+				"app.yaml":                "",
+				"base/kustomization.yaml": `resources: [app.yaml]`,
+				"base/app.yaml":           "",
+			},
+		},
 	}
 	for _, test := range tests {
 		testutil.Run(t, test.description, func(t *testutil.T) {