@commercetools-frontend/mc-html-template

This package contains utils and scripts related to the index.html for a Custom Application.

Install

$ npm install --save @commercetools-frontend/mc-html-template

API

generateTemplate

This method will return the template HTML document with the provided CSS/JS scripts injected.

NOTE that the HTML document will still have the placeholders (see replaceHtmlPlaceholders)

type TGenerateTemplateOptions = {
  cssImports?: string[];
  scriptImports?: string[];
};

function generateTemplate({
  cssImports = [],
  scriptImports = [],
}: TGenerateTemplateOptions);

replaceHtmlPlaceholders

This method will replace the placeholders defined in the HTML document based on the application config.

This method should be used as the final step to get the fully compiled index.html.

At the moment we define the following placeholders:

• __CDN_URL__: the cdnUrl value defined in the application config
• __MC_API_URL__: the mcApiUrl value defined in the application config
• __LOADING_SCREEN_CSS__: (defined internally) the CSS for the loading animation in case the page takes longer to load
• __LOADING_SCREEN_JS__: (defined internally) the JS for the loading animation in case the page takes longer to load
• __APP_ENVIRONMENT__: the sanitized application config environment, which will be available at the global variable window.app
• __CSP__: the generated Content-Security-Policy directives, defined as an HTML meta tag

type TReplaceHtmlPlaceholdersOptions = {
  env: ApplicationRuntimeConfig['env'];
  headers: Record<string, string | undefined>;
};

function replaceHtmlPlaceholders(
  indexHtmlContent: string,
  options: TReplaceHtmlPlaceholdersOptions
): string;

compileHtml

This method will compile the template HTML document.

type TCompileHtmlResult = {
  env: ApplicationRuntimeConfig['env'];
  headers: Record<string, string | undefined>;
  indexHtmlContent: string;
};

async function compileHtml(
  indexHtmlTemplatePath: string
): Promise<TCompileHtmlResult>;

processHeaders

This method will return the security headers to be used on the server response, serving the index.html.

The applicationConfig.env is the processed application environment that would be injected as the window.app. The applicationConfig.headers is the processed application headers provided by the user.

The return value of the processHeaders function contains the following ready-to-use HTTP headers:

{
  "Strict-Transport-Security": "max-age=31536000",
  "X-XSS-Protection": "1; mode=block",
  "X-Content-Type-Options": "nosniff",
  "X-Frame-Options": "SAMEORIGIN",
  "Content-Security-Policy": "...",
  "Feature-Policies": "..."
}

function processHeaders(
  applicationConfig: ApplicationRuntimeConfig
): Record<string, string | undefined>;

Bundler entry points

The package exposes some special entry points used by specific bundlers to use the HTML template.

Webpack

If you use Webpack with the HtmlWebpackPlugin, you can pass the webpack entry point that will map the Webpack template params to our generic generateTemplate method.

new HtmlWebpackPlugin({
  template: require.resolve(
    '@commercetools-frontend/mc-html-template/webpack'
  ),
  // ...
}),