Decode structures

decoder.go

@@ -21,16 +21,20 @@ func Decode(out interface{}, in string) error {
 // DecodeAST is a lower-level version of Decode. It decodes a
 // raw AST into the given output.
 func DecodeAST(out interface{}, obj *ast.ObjectNode) error {
-	return decode("", *obj, reflect.ValueOf(out).Elem())
+	return decode("root", *obj, reflect.ValueOf(out).Elem())
 }
 
 func decode(name string, n ast.Node, result reflect.Value) error {
 	switch result.Kind() {
+	case reflect.Int:
+		return decodeInt(name, n, result)
 	case reflect.Interface:
 		// When we see an interface, we make our own thing
 		return decodeInterface(name, n, result)
 	case reflect.Map:
 		return decodeMap(name, n, result)
+	case reflect.Slice:
+		return decodeSlice(name, n, result)
 	case reflect.String:
 		return decodeString(name, n, result)
 	default:
@@ -40,15 +44,66 @@ func decode(name string, n ast.Node, result reflect.Value) error {
 	return nil
 }
 
+func decodeInt(name string, raw ast.Node, result reflect.Value) error {
+	n, ok := raw.(ast.LiteralNode)
+	if !ok {
+		return fmt.Errorf("%s: not a literal type", name)
+	}
+
+	switch n.Type {
+	case ast.ValueTypeInt:
+		result.SetInt(int64(n.Value.(int)))
+	default:
+		return fmt.Errorf("%s: unknown type %s", name, n.Type)
+	}
+
+	return nil
+}
+
 func decodeInterface(name string, raw ast.Node, result reflect.Value) error {
 	var set reflect.Value
+	redecode := true
 
 	switch n := raw.(type) {
 	case ast.ObjectNode:
+		redecode = false
 		result := make(map[string]interface{})
+
+		for _, elem := range n.Elem {
+			n := elem.(ast.AssignmentNode)
+
+			raw := new(interface{})
+			err := decode(
+				name, n.Value, reflect.Indirect(reflect.ValueOf(raw)))
+			if err != nil {
+				return err
+			}
+
+			result[n.Key()] = *raw
+		}
+
+		set = reflect.ValueOf(result)
+	case ast.ListNode:
+		redecode = false
+		result := make([]interface{}, 0, len(n.Elem))
+
+		for _, elem := range n.Elem {
+			raw := new(interface{})
+			err := decode(
+				name, elem, reflect.Indirect(reflect.ValueOf(raw)))
+			if err != nil {
+				return err
+			}
+
+			result = append(result, *raw)
+		}
+
 		set = reflect.ValueOf(result)
 	case ast.LiteralNode:
 		switch n.Type {
+		case ast.ValueTypeInt:
+			var result int
+			set = reflect.Indirect(reflect.New(reflect.TypeOf(result)))
 		case ast.ValueTypeString:
 			set = reflect.Indirect(reflect.New(reflect.TypeOf("")))
 		default:
@@ -62,10 +117,12 @@ func decodeInterface(name string, raw ast.Node, result reflect.Value) error {
 			name, raw)
 	}
 
-	// Revisit the node so that we can use the newly instantiated
-	// thing and populate it.
-	if err := decode(name, raw, set); err != nil {
-		return err
+	if redecode {
+		// Revisit the node so that we can use the newly instantiated
+		// thing and populate it.
+		if err := decode(name, raw, set); err != nil {
+			return err
+		}
 	}
 
 	// Set the result to what its supposed to be, then reset
@@ -100,7 +157,7 @@ func decodeMap(name string, raw ast.Node, result reflect.Value) error {
 		n := elem.(ast.AssignmentNode)
 
 		// Make the field name
-		fieldName := fmt.Sprintf("%s[%s]", name, n.Key())
+		fieldName := fmt.Sprintf("%s.%s", name, n.Key())
 
 		// Get the key/value as reflection values
 		key := reflect.ValueOf(n.Key())
@@ -126,6 +183,19 @@ func decodeMap(name string, raw ast.Node, result reflect.Value) error {
 	return nil
 }
 
+func decodeSlice(name string, raw ast.Node, result reflect.Value) error {
+	// Create the slice
+	resultType := result.Type()
+	resultElemType := resultType.Elem()
+	resultSliceType := reflect.SliceOf(resultElemType)
+	resultSlice := reflect.MakeSlice(
+		resultSliceType, 0, 0)
+
+	result.Set(resultSlice)
+
+	return nil
+}
+
 func decodeString(name string, raw ast.Node, result reflect.Value) error {
 	n, ok := raw.(ast.LiteralNode)
 	if !ok {
@@ -134,7 +204,6 @@ func decodeString(name string, raw ast.Node, result reflect.Value) error {
 
 	switch n.Type {
 	case ast.ValueTypeString:
-		println(n.Value.(string))
 		result.SetString(n.Value.(string))
 	default:
 		return fmt.Errorf("%s: unknown type %s", name, n.Type)

decoder_test.go

@@ -20,6 +20,13 @@ func TestDecode(t *testing.T) {
 				"foo": "bar",
 			},
 		},
+		{
+			"structure.hcl",
+			false,
+			map[string]interface{}{
+				"foo": "bar",
+			},
+		},
 	}
 
 	for _, tc := range cases {

hcl/parse.y

@@ -21,9 +21,9 @@ import (
 
 %type   <list> list
 %type   <klist> objectlist
-%type   <kitem> objectitem
+%type   <kitem> objectitem block
 %type   <listitem> listitem
-%type   <obj> block object
+%type   <obj> object
 %type   <str> blockId
 
 %token  <num> NUMBER
@@ -104,15 +104,26 @@ objectitem:
 block:
 	blockId object
 	{
-		$$ = $2
-		$$.K = $1
+		$$ = ast.AssignmentNode{
+			K:     $1,
+			Value: ast.ListNode{
+				Elem: []ast.Node{$2},
+			},
+		}
 	}
 |	blockId block
 	{
-		$$ = ast.ObjectNode{
-			K:    $1,
+		obj := ast.ObjectNode{
+			K:    $2.Key(),
 			Elem: []ast.KeyedNode{$2},
 		}
+
+		$$ = ast.AssignmentNode{
+			K:     $1,
+			Value: ast.ListNode{
+				Elem: []ast.Node{obj},
+			},
+		}
 	}
 
 blockId:

hcl/y.go

@@ -49,7 +49,7 @@ const hclEofCode = 1
 const hclErrCode = 2
 const hclMaxDepth = 200
 
-//line parse.y:154
+//line parse.y:165
 
 //line yacctab:1
 var hclExca = []int{
@@ -81,12 +81,12 @@ var hclPact = []int{
 }
 var hclPgo = []int{
 
-	0, 29, 4, 28, 0, 25, 12, 26, 5,
+	0, 29, 4, 28, 25, 0, 12, 26, 5,
 }
 var hclR1 = []int{
 
 	0, 8, 2, 2, 6, 6, 3, 3, 3, 3,
-	3, 5, 5, 7, 7, 1, 1, 4, 4,
+	3, 4, 4, 7, 7, 1, 1, 5, 5,
 }
 var hclR2 = []int{
 
@@ -95,9 +95,9 @@ var hclR2 = []int{
 }
 var hclChk = []int{
 
-	-1000, -8, -2, -3, 6, -5, -7, 9, -2, 7,
-	-6, -5, 10, 6, 4, 9, -6, 12, -2, 11,
-	-1, -4, 4, 9, 11, 13, 5, -4,
+	-1000, -8, -2, -3, 6, -4, -7, 9, -2, 7,
+	-6, -4, 10, 6, 4, 9, -6, 12, -2, 11,
+	-1, -5, 4, 9, 11, 13, 5, -5,
 }
 var hclDef = []int{
 
@@ -412,44 +412,55 @@ hcldefault:
 	case 10:
 		//line parse.y:100
 		{
-			hclVAL.kitem = hclS[hclpt-0].obj
+			hclVAL.kitem = hclS[hclpt-0].kitem
 		}
 	case 11:
 		//line parse.y:106
 		{
-			hclVAL.obj = hclS[hclpt-0].obj
-			hclVAL.obj.K = hclS[hclpt-1].str
+			hclVAL.kitem = ast.AssignmentNode{
+				K: hclS[hclpt-1].str,
+				Value: ast.ListNode{
+					Elem: []ast.Node{hclS[hclpt-0].obj},
+				},
+			}
 		}
 	case 12:
-		//line parse.y:111
+		//line parse.y:115
 		{
-			hclVAL.obj = ast.ObjectNode{
-				K:    hclS[hclpt-1].str,
-				Elem: []ast.KeyedNode{hclS[hclpt-0].obj},
+			obj := ast.ObjectNode{
+				K:    hclS[hclpt-0].kitem.Key(),
+				Elem: []ast.KeyedNode{hclS[hclpt-0].kitem},
+			}
+
+			hclVAL.kitem = ast.AssignmentNode{
+				K: hclS[hclpt-1].str,
+				Value: ast.ListNode{
+					Elem: []ast.Node{obj},
+				},
 			}
 		}
 	case 13:
-		//line parse.y:120
+		//line parse.y:131
 		{
 			hclVAL.str = hclS[hclpt-0].str
 		}
 	case 14:
-		//line parse.y:124
+		//line parse.y:135
 		{
 			hclVAL.str = hclS[hclpt-0].str
 		}
 	case 15:
-		//line parse.y:130
+		//line parse.y:141
 		{
 			hclVAL.list = []ast.Node{hclS[hclpt-0].listitem}
 		}
 	case 16:
-		//line parse.y:134
+		//line parse.y:145
 		{
 			hclVAL.list = append(hclS[hclpt-2].list, hclS[hclpt-0].listitem)
 		}
 	case 17:
-		//line parse.y:140
+		//line parse.y:151
 		{
 			hclVAL.listitem = ast.LiteralNode{
 				Type:  ast.ValueTypeInt,
@@ -457,7 +468,7 @@ hcldefault:
 			}
 		}
 	case 18:
-		//line parse.y:147
+		//line parse.y:158
 		{
 			hclVAL.listitem = ast.LiteralNode{
 				Type:  ast.ValueTypeString,

test-fixtures/structure.hcl

@@ -0,0 +1,5 @@
+// This is a test structure for the lexer
+foo bar "baz" {
+	key = 7
+	foo = "bar"
+}