From 6aa063aeee03f08327afe162bfece2dcb51d0438 Mon Sep 17 00:00:00 2001
From: rafiramadhana <rf.ramadhana@gmail.com>
Date: Thu, 21 Sep 2023 00:02:09 +0700
Subject: [PATCH 1/2] Add validation

Add layer dependencies validation.
---
 internal/layerfile/layerfile.go      | 27 +++++++++++++++-
 internal/layerfile/layerfile_test.go | 46 ++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+), 1 deletion(-)

diff --git a/internal/layerfile/layerfile.go b/internal/layerfile/layerfile.go
index 4fbbc82..d5c22b5 100644
--- a/internal/layerfile/layerfile.go
+++ b/internal/layerfile/layerfile.go
@@ -12,7 +12,10 @@ import (
 	"github.com/ergomake/layerform/pkg/data"
 )
 
-var ErrInvalidDefinitionName = errors.New("invalid layer definition name")
+var (
+	ErrInvalidDefinitionName  = errors.New("invalid layer definition name")
+	ErrDependencyDoesNotExist = errors.New("dependency does not exist")
+)
 
 var alphanumericRegex = regexp.MustCompile("^[A-Za-z0-9][A-Za-z0-9_-]*[A-Za-z0-9]$")
 
@@ -40,6 +43,10 @@ func FromFile(sourceFilepath string) (*layerfile, error) {
 }
 
 func (lf *layerfile) ToLayers() ([]*data.LayerDefinition, error) {
+	if err := lf.validateLayersDependencies(); err != nil {
+		return nil, errors.Wrap(err, "fail to validate layers dependencies")
+	}
+
 	dir := path.Dir(lf.sourceFilepath)
 
 	dataLayers := make([]*data.LayerDefinition, len(lf.Layers))
@@ -89,3 +96,21 @@ func (lf *layerfile) ToLayers() ([]*data.LayerDefinition, error) {
 
 	return dataLayers, nil
 }
+
+func (lf *layerfile) validateLayersDependencies() error {
+	names := make(map[string]struct{})
+
+	for _, l := range lf.Layers {
+		names[l.Name] = struct{}{}
+	}
+
+	for _, l := range lf.Layers {
+		for _, d := range l.Dependencies {
+			if _, ok := names[d]; !ok {
+				return errors.Wrap(ErrDependencyDoesNotExist, d)
+			}
+		}
+	}
+
+	return nil
+}
diff --git a/internal/layerfile/layerfile_test.go b/internal/layerfile/layerfile_test.go
index 0ddc43c..f08fbb7 100644
--- a/internal/layerfile/layerfile_test.go
+++ b/internal/layerfile/layerfile_test.go
@@ -135,3 +135,49 @@ func TestToLayers_ValidateNameOfLayerDefinitions(t *testing.T) {
 		})
 	}
 }
+
+func TestToLayers_ValidateAllDependenciesExist(t *testing.T) {
+	tests := []struct {
+		name string
+		lf   layerfile
+		err  error
+	}{
+		{
+			name: "Dependencies don't exist",
+			lf: layerfile{
+				Layers: []layerfileLayer{
+					{
+						Name:         "foo",
+						Dependencies: []string{"bar"},
+					},
+				},
+			},
+			err: ErrDependencyDoesNotExist,
+		},
+		{
+			name: "Dependencies exist",
+			lf: layerfile{
+				Layers: []layerfileLayer{
+					{
+						Name:         "foo",
+						Dependencies: []string{"bar"},
+					},
+					{
+						Name: "bar",
+					},
+				},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := tt.lf.ToLayers()
+			if tt.err == nil {
+				assert.NoError(t, err)
+			} else {
+				assert.ErrorIs(t, err, tt.err)
+			}
+		})
+	}
+}

From d0274ae695c47ccdf7a42c0dccf3ac334c3c6dc5 Mon Sep 17 00:00:00 2001
From: rafiramadhana <rf.ramadhana@gmail.com>
Date: Thu, 21 Sep 2023 09:08:17 +0700
Subject: [PATCH 2/2] Update unit test

Add more test cases.
---
 internal/layerfile/layerfile_test.go | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/internal/layerfile/layerfile_test.go b/internal/layerfile/layerfile_test.go
index f08fbb7..593ea55 100644
--- a/internal/layerfile/layerfile_test.go
+++ b/internal/layerfile/layerfile_test.go
@@ -148,7 +148,10 @@ func TestToLayers_ValidateAllDependenciesExist(t *testing.T) {
 				Layers: []layerfileLayer{
 					{
 						Name:         "foo",
-						Dependencies: []string{"bar"},
+						Dependencies: []string{"bar", "baz"},
+					},
+					{
+						Name: "bar",
 					},
 				},
 			},
@@ -168,6 +171,25 @@ func TestToLayers_ValidateAllDependenciesExist(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "Layers have no dependencies",
+			lf: layerfile{
+				Layers: []layerfileLayer{
+					{
+						Name: "foo",
+					},
+					{
+						Name: "bar",
+					},
+				},
+			},
+		},
+		{
+			name: "No layers",
+			lf: layerfile{
+				Layers: []layerfileLayer{},
+			},
+		},
 	}
 
 	for _, tt := range tests {