feat(cli): Add templateOptions param to pass additional data to custom template (#792)

* Add templateOptions param to pass additional data to custom template
* Update README for ReDoc cli

cli/README.md

@@ -17,5 +17,6 @@ Some examples:
 - Bundle with main color changed to `orange`: <br> `$ redoc-cli bundle [spec] --options.theme.colors.primary.main=orange`
 - Serve with `nativeScrollbars` option set to true: <br> `$ redoc-cli serve [spec] --options.nativeScrollbars`
 - Bundle using custom template (check [default template](https://github.com/Rebilly/ReDoc/blob/master/cli/template.hbs) for reference): <br> `$ redoc-cli bundle [spec] -t custom.hbs`
+- Bundle using custom template and add custom `templateOptions`: <br> `$ redoc-cli bundle [spec] -t custom.hbs --templateOptions.metaDescription "Page meta description"`
 
 For more details run `redoc-cli --help`.

cli/index.ts

@@ -26,6 +26,7 @@ interface Options {
   output?: string;
   title?: string;
   templateFileName?: string;
+  templateOptions?: any;
   redocOptions?: any;
 }
 
@@ -65,6 +66,7 @@ YargsParser.command(
       ssr: argv.ssr,
       watch: argv.watch,
       templateFileName: argv.template,
+      templateOptions: argv.templateOptions || {},
       redocOptions: argv.options || {},
     };
 
@@ -112,6 +114,7 @@ YargsParser.command(
         cdn: argv.cdn,
         title: argv.title,
         templateFileName: argv.template,
+        templateOptions: argv.templateOptions || {},
         redocOptions: argv.options || {},
       };
 
@@ -128,6 +131,9 @@ YargsParser.command(
     describe: 'Path to handlebars page template, see https://git.io/vh8fP for the example ',
     type: 'string',
   })
+  .options('templateOptions', {
+    describe: 'Additional options that you want pass to template. Use dot notation, e.g. templateOptions.metaDescription',
+  })
   .options('options', {
     describe: 'ReDoc options, use dot notation, e.g. options.nativeScrollbars',
   }).argv;
@@ -207,7 +213,7 @@ async function bundle(pathToSpec, options: Options = {}) {
 async function getPageHTML(
   spec: any,
   pathToSpec: string,
-  { ssr, cdn, title, templateFileName, redocOptions = {} }: Options,
+  { ssr, cdn, title, templateFileName, templateOptions, redocOptions = {} }: Options,
 ) {
   let html;
   let css;
@@ -250,6 +256,7 @@ async function getPageHTML(
       : `<script>${redocStandaloneSrc}</script>`) + css
       : '<script src="redoc.standalone.js"></script>',
     title,
+    templateOptions,
   });
 }