config: can parse outputs

config/config.go

@@ -15,6 +15,7 @@ type Config struct {
 	ProviderConfigs map[string]*ProviderConfig
 	Resources       []*Resource
 	Variables       map[string]*Variable
+	Outputs         map[string]*Output
 }
 
 // ProviderConfig is the configuration for a resource provider.
@@ -42,6 +43,13 @@ type Variable struct {
 	defaultSet  bool
 }
 
+// Output is an output defined within the configuration. An output is
+// resulting data that is highlighted by Terraform when finished.
+type Output struct {
+	Name      string
+	RawConfig *RawConfig
+}
+
 // An InterpolatedVariable is a variable that is embedded within a string
 // in the configuration, such as "hello ${world}" (world in this case is
 // an interpolated variable).

config/loader_libucl.go

@@ -78,6 +78,16 @@ func (t *libuclConfigurable) Config() (*Config, error) {
 		}
 	}
 
+	// Build the outputs
+	if outputs := t.Object.Get("output"); outputs != nil {
+		var err error
+		config.Outputs, err = loadOutputsLibucl(outputs)
+		outputs.Close()
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	return config, nil
 }
 
@@ -145,6 +155,52 @@ func loadFileLibucl(root string) (configurable, []string, error) {
 	return result, importPaths, nil
 }
 
+// LoadOutputsLibucl recurses into the given libucl object and turns
+// it into a mapping of outputs.
+func loadOutputsLibucl(o *libucl.Object) (map[string]*Output, error) {
+	objects := make(map[string]*libucl.Object)
+
+	// Iterate over all the "output" blocks and get the keys along with
+	// their raw configuration objects. We'll parse those later.
+	iter := o.Iterate(false)
+	for o1 := iter.Next(); o1 != nil; o1 = iter.Next() {
+		iter2 := o1.Iterate(true)
+		for o2 := iter2.Next(); o2 != nil; o2 = iter2.Next() {
+			objects[o2.Key()] = o2
+			defer o2.Close()
+		}
+
+		o1.Close()
+		iter2.Close()
+	}
+	iter.Close()
+
+	// Go through each object and turn it into an actual result.
+	result := make(map[string]*Output)
+	for n, o := range objects {
+		var config map[string]interface{}
+
+		if err := o.Decode(&config); err != nil {
+			return nil, err
+		}
+
+		rawConfig, err := NewRawConfig(config)
+		if err != nil {
+			return nil, fmt.Errorf(
+				"Error reading config for output %s: %s",
+				n,
+				err)
+		}
+
+		result[n] = &Output{
+			Name:      n,
+			RawConfig: rawConfig,
+		}
+	}
+
+	return result, nil
+}
+
 // LoadProvidersLibucl recurses into the given libucl object and turns
 // it into a mapping of provider configs.
 func loadProvidersLibucl(o *libucl.Object) (map[string]*ProviderConfig, error) {

config/loader_test.go

@@ -39,6 +39,11 @@ func TestLoadBasic(t *testing.T) {
 	if actual != strings.TrimSpace(basicResourcesStr) {
 		t.Fatalf("bad:\n%s", actual)
 	}
+
+	actual = outputsStr(c.Outputs)
+	if actual != strings.TrimSpace(basicOutputsStr) {
+		t.Fatalf("bad:\n%s", actual)
+	}
 }
 
 func TestLoadBasic_import(t *testing.T) {
@@ -92,6 +97,40 @@ func TestLoad_variables(t *testing.T) {
 	}
 }
 
+func outputsStr(os map[string]*Output) string {
+	ns := make([]string, 0, len(os))
+	for n, _ := range os {
+		ns = append(ns, n)
+	}
+	sort.Strings(ns)
+
+	result := ""
+	for _, n := range ns {
+		o := os[n]
+
+		result += fmt.Sprintf("%s\n", n)
+
+		if len(o.RawConfig.Variables) > 0 {
+			result += fmt.Sprintf("  vars\n")
+			for _, rawV := range o.RawConfig.Variables {
+				kind := "unknown"
+				str := rawV.FullKey()
+
+				switch rawV.(type) {
+				case *ResourceVariable:
+					kind = "resource"
+				case *UserVariable:
+					kind = "user"
+				}
+
+				result += fmt.Sprintf("    %s: %s\n", kind, str)
+			}
+		}
+	}
+
+	return strings.TrimSpace(result)
+}
+
 // This helper turns a provider configs field into a deterministic
 // string value for comparison in tests.
 func providerConfigsStr(pcs map[string]*ProviderConfig) string {
@@ -219,6 +258,12 @@ func variablesStr(vs map[string]*Variable) string {
 	return strings.TrimSpace(result)
 }
 
+const basicOutputsStr = `
+web_ip
+  vars
+    resource: aws_instance.web.private_ip
+`
+
 const basicProvidersStr = `
 aws
   access_key

config/test-fixtures/basic.tf

@@ -32,3 +32,7 @@ resource aws_instance "web" {
 resource "aws_instance" "db" {
     security_groups = "${aws_security_group.firewall.*.id}"
 }
+
+output "web_ip" {
+    value = "${aws_instance.web.private_ip}"
+}