From fbda5b119a68d091431ed06098b1fc83caaebd16 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Thu, 21 May 2015 13:40:33 -0600
Subject: [PATCH] template: variable parsing

---
 template/parse.go                             | 20 ++++++++++++++++
 template/parse_test.go                        | 24 +++++++++++++++++++
 .../test-fixtures/parse-variable-default.json |  5 ++++
 .../parse-variable-required.json              |  5 ++++
 4 files changed, 54 insertions(+)
 create mode 100644 template/test-fixtures/parse-variable-default.json
 create mode 100644 template/test-fixtures/parse-variable-required.json

diff --git a/template/parse.go b/template/parse.go
index a96117111..47d97effa 100644
--- a/template/parse.go
+++ b/template/parse.go
@@ -30,6 +30,26 @@ func (r *rawTemplate) Template() (*Template, error) {
 	var result Template
 	var errs error
 
+	// Gather the variables
+	if len(r.Variables) > 0 {
+		result.Variables = make(map[string]*Variable, len(r.Variables))
+	}
+	for k, rawV := range r.Variables {
+		var v Variable
+
+		// Variable is required if the value is exactly nil
+		v.Required = rawV == nil
+
+		// Weak decode the default if we have one
+		if err := r.decoder(&v.Default, nil).Decode(rawV); err != nil {
+			errs = multierror.Append(errs, fmt.Errorf(
+				"variable %s: %s", k, err))
+			continue
+		}
+
+		result.Variables[k] = &v
+	}
+
 	// Let's start by gathering all the builders
 	if len(r.Builders) > 0 {
 		result.Builders = make(map[string]*Builder, len(r.Builders))
diff --git a/template/parse_test.go b/template/parse_test.go
index 2c5b8f735..fcf7fcf29 100644
--- a/template/parse_test.go
+++ b/template/parse_test.go
@@ -117,6 +117,30 @@ func TestParse(t *testing.T) {
 			nil,
 			true,
 		},
+
+		{
+			"parse-variable-default.json",
+			&Template{
+				Variables: map[string]*Variable{
+					"foo": &Variable{
+						Default: "foo",
+					},
+				},
+			},
+			false,
+		},
+
+		{
+			"parse-variable-required.json",
+			&Template{
+				Variables: map[string]*Variable{
+					"foo": &Variable{
+						Required: true,
+					},
+				},
+			},
+			false,
+		},
 	}
 
 	for _, tc := range cases {
diff --git a/template/test-fixtures/parse-variable-default.json b/template/test-fixtures/parse-variable-default.json
new file mode 100644
index 000000000..05192b64d
--- /dev/null
+++ b/template/test-fixtures/parse-variable-default.json
@@ -0,0 +1,5 @@
+{
+    "variables": {
+        "foo": "foo"
+    }
+}
diff --git a/template/test-fixtures/parse-variable-required.json b/template/test-fixtures/parse-variable-required.json
new file mode 100644
index 000000000..ca6458aaa
--- /dev/null
+++ b/template/test-fixtures/parse-variable-required.json
@@ -0,0 +1,5 @@
+{
+    "variables": {
+        "foo": null
+    }
+}