Create variables.md in initSite

Author: rachx

lib/Site.js

@@ -18,7 +18,7 @@ const BOILERPLATE_FOLDER_NAME = '_boilerplates';
 const SITE_ASSET_FOLDER_NAME = 'asset';
 const TEMPLATE_ROOT_FOLDER_NAME = 'template';
 const TEMPLATE_SITE_ASSET_FOLDER_NAME = 'markbind';
-const USER_VARIABLES_PATH = '_system/variables.md';
+const USER_VARIABLES_PATH = '_markbind/variables.md';
 
 const SITE_CONFIG_DEFAULT = {
   baseUrl: '',
@@ -40,6 +40,11 @@ const SITE_CONFIG_DEFAULT = {
 
 const INDEX_MARKDOWN_DEFAULT = '# Hello world\nWelcome to your page generated with MarkBind.\n';
 
+const USER_VARIABLES_DEFAULT = '<span id="example">\n'
+  + 'To inject this HTML segment in your markbind files, use {{ example }} where you want to place it.\n'
+  + 'More generally, surround the segment\'s id with double curly braces.\n'
+  + '</span>';
+
 function Site(rootPath, outputPath) {
   this.rootPath = rootPath;
   this.outputPath = outputPath;
@@ -86,6 +91,7 @@ Site.initSite = function (rootPath) {
   const boilerplatePath = path.join(rootPath, BOILERPLATE_FOLDER_NAME);
   const configPath = path.join(rootPath, SITE_CONFIG_NAME);
   const indexPath = path.join(rootPath, INDEX_MARKDOWN_FILE);
+  const userDefinedVariablesPath = path.join(rootPath, USER_VARIABLES_PATH);
   // TODO: log the generate info
   return new Promise((resolve, reject) => {
     fs.accessAsync(boilerplatePath)
@@ -109,6 +115,13 @@ Site.initSite = function (rootPath) {
         }
         return fs.outputFileAsync(indexPath, INDEX_MARKDOWN_DEFAULT);
       })
+      .then(() => fs.accessAsync(userDefinedVariablesPath))
+      .catch(() => {
+        if (fs.existsSync(userDefinedVariablesPath)) {
+          return Promise.resolve();
+        }
+        return fs.outputFileAsync(userDefinedVariablesPath, USER_VARIABLES_DEFAULT);
+      })
       .then(resolve)
       .catch(reject);
   });