From fa934d96d094e34a36ba728ded137dc17be932dd Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Tue, 21 Apr 2015 22:07:52 +0200
Subject: [PATCH] helper/schema: FieldReaderConfig detects computed maps

---
 helper/schema/field_reader_config.go      | 53 ++++++++++++----
 helper/schema/field_reader_config_test.go | 73 +++++++++++++++++++++++
 terraform/resource.go                     |  9 +++
 3 files changed, 125 insertions(+), 10 deletions(-)

diff --git a/helper/schema/field_reader_config.go b/helper/schema/field_reader_config.go
index 3c01e8de2..a6edef099 100644
--- a/helper/schema/field_reader_config.go
+++ b/helper/schema/field_reader_config.go
@@ -105,34 +105,67 @@ func (r *ConfigFieldReader) readField(
 }
 
 func (r *ConfigFieldReader) readMap(k string) (FieldReadResult, error) {
-	mraw, ok := r.Config.Get(k)
+	// We want both the raw value and the interpolated. We use the interpolated
+	// to store actual values and we use the raw one to check for
+	// computed keys.
+	mraw, ok := r.Config.GetRaw(k)
 	if !ok {
 		return FieldReadResult{}, nil
 	}
 
 	result := make(map[string]interface{})
+	computed := false
 	switch m := mraw.(type) {
 	case []interface{}:
-		for _, innerRaw := range m {
-			for k, v := range innerRaw.(map[string]interface{}) {
-				result[k] = v
+		for i, innerRaw := range m {
+			for ik, _ := range innerRaw.(map[string]interface{}) {
+				key := fmt.Sprintf("%s.%d.%s", k, i, ik)
+				if r.Config.IsComputed(key) {
+					computed = true
+					break
+				}
+
+				v, _ := r.Config.Get(key)
+				result[ik] = v
 			}
 		}
 	case []map[string]interface{}:
-		for _, innerRaw := range m {
-			for k, v := range innerRaw {
-				result[k] = v
+		for i, innerRaw := range m {
+			for ik, _ := range innerRaw {
+				key := fmt.Sprintf("%s.%d.%s", k, i, ik)
+				if r.Config.IsComputed(key) {
+					computed = true
+					break
+				}
+
+				v, _ := r.Config.Get(key)
+				result[ik] = v
 			}
 		}
 	case map[string]interface{}:
-		result = m
+		for ik, _ := range m {
+			key := fmt.Sprintf("%s.%s", k, ik)
+			if r.Config.IsComputed(key) {
+				computed = true
+				break
+			}
+
+			v, _ := r.Config.Get(key)
+			result[ik] = v
+		}
 	default:
 		panic(fmt.Sprintf("unknown type: %#v", mraw))
 	}
 
+	var value interface{}
+	if !computed {
+		value = result
+	}
+
 	return FieldReadResult{
-		Value:  result,
-		Exists: true,
+		Value:    value,
+		Exists:   true,
+		Computed: computed,
 	}, nil
 }
 
diff --git a/helper/schema/field_reader_config_test.go b/helper/schema/field_reader_config_test.go
index 33672eff2..96028a89c 100644
--- a/helper/schema/field_reader_config_test.go
+++ b/helper/schema/field_reader_config_test.go
@@ -135,6 +135,79 @@ func TestConfigFieldReader_DefaultHandling(t *testing.T) {
 	}
 }
 
+func TestConfigFieldReader_ComputedMap(t *testing.T) {
+	schema := map[string]*Schema{
+		"map": &Schema{
+			Type:     TypeMap,
+			Computed: true,
+		},
+	}
+
+	cases := map[string]struct {
+		Addr   []string
+		Result FieldReadResult
+		Config *terraform.ResourceConfig
+		Err    bool
+	}{
+		"set, normal": {
+			[]string{"map"},
+			FieldReadResult{
+				Value: map[string]interface{}{
+					"foo": "bar",
+				},
+				Exists:   true,
+				Computed: false,
+			},
+			testConfig(t, map[string]interface{}{
+				"map": map[string]interface{}{
+					"foo": "bar",
+				},
+			}),
+			false,
+		},
+
+		"computed element": {
+			[]string{"map"},
+			FieldReadResult{
+				Exists:   true,
+				Computed: true,
+			},
+			testConfigInterpolate(t, map[string]interface{}{
+				"map": map[string]interface{}{
+					"foo": "${var.foo}",
+				},
+			}, map[string]ast.Variable{
+				"var.foo": ast.Variable{
+					Value: config.UnknownVariableValue,
+					Type:  ast.TypeString,
+				},
+			}),
+			false,
+		},
+	}
+
+	for name, tc := range cases {
+		r := &ConfigFieldReader{
+			Schema: schema,
+			Config: tc.Config,
+		}
+		out, err := r.ReadField(tc.Addr)
+		if (err != nil) != tc.Err {
+			t.Fatalf("%s: err: %s", name, err)
+		}
+		if s, ok := out.Value.(*Set); ok {
+			// If it is a set, convert to the raw map
+			out.Value = s.m
+			if len(s.m) == 0 {
+				out.Value = nil
+			}
+		}
+		if !reflect.DeepEqual(tc.Result, out) {
+			t.Fatalf("%s: bad: %#v", name, out)
+		}
+	}
+}
+
 func TestConfigFieldReader_ComputedSet(t *testing.T) {
 	schema := map[string]*Schema{
 		"strSet": &Schema{
diff --git a/terraform/resource.go b/terraform/resource.go
index 9dacbc7c5..5b9fbf7d2 100644
--- a/terraform/resource.go
+++ b/terraform/resource.go
@@ -134,6 +134,15 @@ func (c *ResourceConfig) Get(k string) (interface{}, bool) {
 	return c.get(k, c.Raw)
 }
 
+// GetRaw looks up a configuration value by key and returns the value,
+// from the raw, uninterpolated config.
+//
+// The second return value is true if the get was successful. Get will
+// not succeed if the value is being computed.
+func (c *ResourceConfig) GetRaw(k string) (interface{}, bool) {
+	return c.get(k, c.Raw)
+}
+
 // IsComputed returns whether the given key is computed or not.
 func (c *ResourceConfig) IsComputed(k string) bool {
 	_, ok := c.get(k, c.Config)