Adding simple require functionality to js (#58)

* Adding simple require functionality to js

* comment

js/js.go

@@ -2,6 +2,8 @@ package js
 
 import (
 	"encoding/json"
+	"fmt"
+	"io/ioutil"
 
 	"github.com/StackExchange/dnscontrol/models"
 
@@ -14,6 +16,8 @@ import (
 func ExecuteJavascript(script string, devMode bool) (*models.DNSConfig, error) {
 	vm := otto.New()
 
+	vm.Set("require", require)
+
 	helperJs := GetHelpers(devMode)
 	// run helper script to prime vm and initialize variables
 	if _, err := vm.Run(helperJs); err != nil {
@@ -44,3 +48,17 @@ func ExecuteJavascript(script string, devMode bool) (*models.DNSConfig, error) {
 func GetHelpers(devMode bool) string {
 	return _escFSMustString(devMode, "/helpers.js")
 }
+
+func require(call otto.FunctionCall) otto.Value {
+	file := call.Argument(0).String()
+	fmt.Printf("requiring: %s\n", file)
+	data, err := ioutil.ReadFile(file)
+	if err != nil {
+		panic(err)
+	}
+	_, err = call.Otto.Run(string(data))
+	if err != nil {
+		panic(err)
+	}
+	return otto.TrueValue()
+}

js/js_test.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"path/filepath"
 	"testing"
+	"unicode"
 
 	"github.com/StackExchange/dnscontrol/models"
 )
@@ -25,7 +26,8 @@ func TestParsedFiles(t *testing.T) {
 		t.Fatal(err)
 	}
 	for _, f := range files {
-		if filepath.Ext(f.Name()) != ".js" {
+		//run all js files that start with a number. Skip others.
+		if filepath.Ext(f.Name()) != ".js" || !unicode.IsNumber(rune(f.Name()[0])) {
 			continue
 		}
 		t.Log(f.Name(), "------")

js/parse_tests/008-import.js

@@ -0,0 +1,2 @@
+
+require("js/parse_tests/import.js")

js/parse_tests/008-import.json

@@ -0,0 +1,19 @@
+{
+		  "registrars": [],
+		  "dns_providers": [],
+		  "domains": [
+		    {
+		      "name": "foo.com",
+		      "registrar": "none",
+		      "dnsProviders": {},
+		      "records": [
+		        {
+		          "type": "A",
+		          "name": "@",
+		          "target": "1.2.3.4"
+		        }
+		      ],
+		      "keepunknown": false
+		    }
+		  ]
+		}

js/parse_tests/import.js

@@ -0,0 +1,3 @@
+D("foo.com","none",
+    A("@","1.2.3.4")
+);