Halfway through in refactoring the report generation to a separate process running asynchronously of the Express server.

lib/handlebars-helpers.js

@@ -0,0 +1,46 @@
+'use strict';
+
+const _ = require('../lib/translate')._;
+
+module.exports.registerHelpers = (handlebars) => {
+    // {{#translate}}abc{{/translate}}
+    handlebars.registerHelper('translate', function (context, options) { // eslint-disable-line prefer-arrow-callback
+        if (typeof options === 'undefined' && context) {
+            options = context;
+            context = false;
+        }
+
+        let result = _(options.fn(this)); // eslint-disable-line no-invalid-this
+
+        if (Array.isArray(context)) {
+            result = util.format(result, ...context);
+        }
+        return new handlebars.SafeString(result);
+    });
+
+
+    /* Credits to http://chrismontrois.net/2016/01/30/handlebars-switch/
+
+     {{#switch letter}}
+     {{#case "a"}}
+     A is for alpaca
+     {{/case}}
+     {{#case "b"}}
+     B is for bluebird
+     {{/case}}
+     {{/switch}}
+     */
+    handlebars.registerHelper("switch", function(value, options) {
+        this._switch_value_ = value;
+        var html = options.fn(this); // Process the body of the switch block
+        delete this._switch_value_;
+        return html;
+    });
+
+    handlebars.registerHelper("case", function(value, options) {
+        if (value == this._switch_value_) {
+            return options.fn(this);
+        }
+    });
+
+};