handlebars-webpack-plugin

Server-side template rendering using Handlebars.

npm install handlebars-webpack-plugin --save-dev

Usage

In your webpack config register and setup the handlebars plugin

const path = require("path");
const HandlebarsPlugin = require("handlebars-webpack-plugin");
 
const webpackConfig = {
 
  plugins: [
 
    new HandlebarsPlugin({
      // path to hbs entry file(s). Also supports nested directories if write path.join(process.cwd(), "app", "src", "**", "*.hbs"),
      entry: path.join(process.cwd(), "app", "src", "*.hbs"),
      // output path and filename(s). This should lie within the webpacks output-folder
      // if ommited, the input filepath stripped of its extension will be used
      output: path.join(process.cwd(), "build", "[name].html"),
      // you can also add a [path] variable, which will emit the files with their relative path, like
      // output: path.join(process.cwd(), "build", [path], "[name].html"),
      
      // data passed to main hbs template: `main-template(data)`
      data: require("./app/data/project.json"),
      // or add it as filepath to rebuild data on change using webpack-dev-server
      data: path.join(__dirname, "app/data/project.json"),
 
      // globbed path to partials, where folder/filename is unique
      partials: [
        path.join(process.cwd(), "app", "src", "components", "*", "*.hbs")
      ],
 
      // register custom helpers. May be either a function or a glob-pattern
      helpers: {
        nameOfHbsHelper: Function.prototype,
        projectHelpers: path.join(process.cwd(), "app", "helpers", "*.helper.js")
      },
 
      // hooks
      // getTargetFilepath: function (filepath, outputTemplate) {},
      // getPartialId: function (filePath) {}
      onBeforeSetup: function (Handlebars) {},
      onBeforeAddPartials: function (Handlebars, partialsMap) {},
      onBeforeCompile: function (Handlebars, templateContent) {},
      onBeforeRender: function (Handlebars, data, filename) {},
      onBeforeSave: function (Handlebars, resultHtml, filename) {},
      onDone: function (Handlebars, filename) {}
    })
  ]
};

Partial ids are registered by parentFolder/filename (without file extensions)

Use handlebars in your main and partials like, i.e.

<body>
  {{> partialFolder/partialName}}
 
  {{> header/header title="page title"}}
 
  {{> partial/content}}
</body>

Options

target filepaths

Per default, the generated filepath of the html-results is defined by the output-property in the plugin-options. To changed the output folder and name, you can pass your custom filepath-helper to the plugin-options like

{
    /**
     * Modify the default output path of each entry-template
     * @param {String} filepath     - the source of the template
     * @param {String} outputTemplate - the filepath template defined in `output`
     * @param {String} rootFolder   - the filepaths rootFolder
     * @return {String} final path, where the rendered html-file should be saved
     */
    getTargetFilepath: function getTargetFilepath(filepath, outputTemplate, rootFolder) {
        const fileName = path.basename(filepath).replace(path.extname(filepath), "");
        return outputTemplate.replace("[name]", fileName);
    };
}

You can find the default implementation in utils/getTargetFilepath.

partial ids

Per default, partials are identified with folder/filename in a hbs-template. e.g. a file in app/partials/page/header.hbs will be registered under page/header and can be included with

{{> page/header title="page title"}}

To change the partial's id you can pass a custom partial-generator to the plugin-options like

{
    /**
     * Modify the hbs partial-id created for a loaded partial
     * @param {String} filePath   - filePath to the loaded partial
     * @return {String} hbs-partialId, per default folder/partialName is used
     */
    getPartialId: function (filePath) {
        return filePath.match(/\/([^/]+\/[^/]+)\.[^.]+$/).pop();
    }
}

Html Webpack Plugin

Use the html-webpack-plugin to generate partials, that are dynamically registered to the handlebars-webpack-plugin

the HtmlWebpackPlugin should be placed before the HandlebarsWebpackPlugin
multiple HtmlWebpackPlugins may be used
per default, the partials get registered to html/<outputfilename>, i.e. a filename /dist/partials/head.hbs will be registered as html/head to handlebars

plugins: [
   new HtmlWebpackPlugin({
    title: "Generic Head Title",
    // the template you want to use
    template: path.join(__dirname, "src", "generatedpartial", "head.hbs"),
    // the output file name
    filename: path.join(__dirname, "dist", "partials", "head.hbs"),
    inject: "head"
  }),
 
  new HandlebarsWebpackPlugin({
 
    htmlWebpackPlugin: {
      enabled: true, // register all partials from html-webpack-plugin, defaults to `false`
      prefix: "html", // where to look for htmlWebpackPlugin output. default is "html"
      HtmlWebpackPlugin // optionally: pass in HtmlWebpackPlugin if it cannot be resolved
    },
 
    entry: path.join(process.cwd(), "src", "hbs", "*.hbs"),
    output: path.join(process.cwd(), "dist", "[name].html"),
 
    partials: [
      path.join(process.cwd(), "html",/* <-- this should match htmlWebpackPlugin.prefix */ "*", "*.hbs"),
      path.join(process.cwd(), "src", "hbs", "*", "*.hbs")
    ]
  })
]

Utilities

Merging input-data

In case you have several json-files that need to be passed to handlebars-compilation, you can build this within your webpack-configuration file. A simple helper can be found in utils/mergeJSON.js, which finds all json files and build a dataObject with { <filename>: <data> }. Example:

const mergeJSON = require('handlebars-webpack-plugin/utils/mergeJSON');
const projectData = mergeJSON(path.join(__dirname, "data/**/*.json"));
// ...
new HandlebarsPlugin({
    // ...
    data: projectData
});

For custom merge behaviour you can add your own merge-helper, following the implementation from utils/mergeJSON.js.