feat: undefined detection

inventory.go

@@ -2,8 +2,7 @@ package skipper
 
 import (
 	"fmt"
-
-	"github.com/davecgh/go-spew/spew"
+	"strings"
 
 	"github.com/lukasjarosch/skipper/data"
 )
@@ -14,14 +13,20 @@ type Scope string
 var (
 	DataScope    Scope = "data"
 	TargetsScope Scope = "targets"
+
+	// UndefinedValue is a value which must be defined during compilation
+	// To ensure all values which can only be set within the target are actually set,
+	// one can use this value.
+	UndefinedValue = data.NewValue("__undefined__")
 )
 
 var (
-	ErrEmptyScope                 = fmt.Errorf("scope is empty")
-	ErrNilRegistry                = fmt.Errorf("registry is nil")
-	ErrScopeDoesNotExist          = fmt.Errorf("scope does not exist")
-	ErrScopeAlreadyRegistered     = fmt.Errorf("scope already registered")
-	ErrTargetCannotIntroducePaths = fmt.Errorf("target cannot introduce new paths")
+	ErrEmptyScope                   = fmt.Errorf("scope is empty")
+	ErrNilRegistry                  = fmt.Errorf("registry is nil")
+	ErrScopeDoesNotExist            = fmt.Errorf("scope does not exist")
+	ErrScopeAlreadyRegistered       = fmt.Errorf("scope already registered")
+	ErrTargetCannotIntroducePaths   = fmt.Errorf("target cannot introduce new paths")
+	ErrUndefinedValueNotOverwritten = fmt.Errorf("undefined value was not overwritten by target")
 )
 
 // Inventory is the top-level abstraction which represents all data.
@@ -122,7 +127,6 @@ func (inv *Inventory) Compile(target data.Path) error {
 		}
 
 		// The path exists within the inventory, overwrite it with the value from the target.
-		spew.Println("OVERWRITTEN", pathWithoutClassName)
 		err = inv.SetPath(pathWithoutClassName, v.Raw)
 		if err != nil {
 			return fmt.Errorf("failed to overwrite path %s: %w", pathWithoutClassName, err)
@@ -133,6 +137,17 @@ func (inv *Inventory) Compile(target data.Path) error {
 		return err
 	}
 
+	// undefined value detection, go through all paths to ensure all values are no 'UndefinedValue'
+	err = inv.WalkValues(func(p data.Path, v data.Value) error {
+		if strings.ToLower(strings.TrimSpace(v.String())) == UndefinedValue.String() {
+			return fmt.Errorf("%w: %s", ErrUndefinedValueNotOverwritten, p)
+		}
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
 	return nil
 }
 

inventory_test.go

@@ -160,8 +160,8 @@ func TestInventoryAbsolutePath(t *testing.T) {
 }
 
 func TestInventory_Compile(t *testing.T) {
-	dataRegistry := func() *Registry {
-		commonClass, err := NewClass("testdata/compile/data/common.yaml", codec.NewYamlCodec(), data.NewPath("common"))
+	dataRegistry := func(class string) *Registry {
+		commonClass, err := NewClass(fmt.Sprintf("testdata/compile/data/%s.yaml", class), codec.NewYamlCodec(), data.NewPath(class))
 		assert.NoError(t, err)
 		dataRegistry := NewRegistry()
 		err = dataRegistry.RegisterClass(commonClass)
@@ -182,7 +182,7 @@ func TestInventory_Compile(t *testing.T) {
 
 	t.Run("valid target", func(t *testing.T) {
 		inventory, _ := NewInventory()
-		err := inventory.RegisterScope(DataScope, dataRegistry())
+		err := inventory.RegisterScope(DataScope, dataRegistry("common"))
 		assert.NoError(t, err)
 		err = inventory.RegisterScope(TargetsScope, targetRegistry("valid"))
 		assert.NoError(t, err)
@@ -204,12 +204,38 @@ func TestInventory_Compile(t *testing.T) {
 
 	t.Run("target cannot introduce paths in the inventory", func(t *testing.T) {
 		inventory, _ := NewInventory()
-		err := inventory.RegisterScope(DataScope, dataRegistry())
+		err := inventory.RegisterScope(DataScope, dataRegistry("common"))
 		assert.NoError(t, err)
 		err = inventory.RegisterScope(TargetsScope, targetRegistry("introduce_paths"))
 		assert.NoError(t, err)
 
 		err = inventory.Compile(data.NewPath("targets.introduce_paths"))
 		assert.ErrorIs(t, err, ErrTargetCannotIntroducePaths)
 	})
+
+	t.Run("error if undefined value is not overwritten", func(t *testing.T) {
+		inventory, _ := NewInventory()
+		err := inventory.RegisterScope(DataScope, dataRegistry("undefined"))
+		assert.NoError(t, err)
+		err = inventory.RegisterScope(TargetsScope, targetRegistry("not_overwritten_undefined"))
+		assert.NoError(t, err)
+
+		err = inventory.Compile(data.NewPath("targets.not_overwritten_undefined"))
+		assert.ErrorIs(t, err, ErrUndefinedValueNotOverwritten)
+	})
+
+	t.Run("no error if undefined value is overwritten", func(t *testing.T) {
+		inventory, _ := NewInventory()
+		err := inventory.RegisterScope(DataScope, dataRegistry("undefined"))
+		assert.NoError(t, err)
+		err = inventory.RegisterScope(TargetsScope, targetRegistry("overwritten_undefined"))
+		assert.NoError(t, err)
+
+		err = inventory.Compile(data.NewPath("targets.overwritten_undefined"))
+		assert.NoError(t, err)
+
+		val, err := inventory.Get("data.undefined.network_cidr")
+		assert.NoError(t, err)
+		assert.Equal(t, "10.0.0.0/8", val.String())
+	})
 }

testdata/compile/data/undefined.yaml

@@ -0,0 +1,2 @@
+undefined:
+  network_cidr: __undefined__

testdata/compile/targets/not_overwritten_undefined.yaml

@@ -0,0 +1,2 @@
+not_overwritten_undefined:
+  lol: nothing

testdata/compile/targets/overwritten_undefined.yaml

@@ -0,0 +1,2 @@
+overwritten_undefined:
+  data.undefined.network_cidr: 10.0.0.0/8