Implemented async barcode generation using async helpers

ref #13

src/PdfCreator.ts

@@ -1,5 +1,4 @@
 import axios from 'axios';
-import bwipjs from "bwip-js";
 import cheerio from "cheerio";
 import fs from "fs";
 import Handlebars from 'handlebars';
@@ -9,6 +8,7 @@ import mime from "mime-types";
 import path from 'path';
 import { PDFDocument } from 'pdf-lib';
 import puppeteer from "puppeteer";
+import { awaitAsyncHandlebarHelpers, helpers } from './asyncHelpers';
 import { Runner } from './models/Runner';
 import { RunnerGroup } from './models/RunnerGroup';
 
@@ -78,18 +78,13 @@ export class PdfCreator {
                     loadPath: path.join(__dirname, '/locales/{{lng}}.json')
                 }
             });
+
+        await Handlebars.registerHelper(helpers);
         await Handlebars.registerHelper('__',
             function (str) {
                 return i18next.t(str, PdfCreator.interpolations).toString();
             }
         );
-        await Handlebars.registerHelper('--bc',
-            function (str) {
-                //TODO: Fix the async behaviour
-                return "data:image"
-                return PdfCreator.generateBarcode("code39", str.toString());
-            }
-        );
         this.browser = await puppeteer.launch({ headless: true, args: minimal_args });
     }
 
@@ -115,7 +110,8 @@ export class PdfCreator {
         await i18next.changeLanguage(locale);
         const template_source = fs.readFileSync(`${this.templateDir}/sponsoring_contract.html`, 'utf8');
         const template = Handlebars.compile(template_source);
-        const result = template({ runners })
+        let result = template({ runners });
+        result = await awaitAsyncHandlebarHelpers(result);
         const pdf = await this.renderPdf(result, { format: "A5", landscape: true });
         return pdf
     }
@@ -190,25 +186,6 @@ export class PdfCreator {
         return <Buffer>(await mergedPdf.save());
     }
 
-    /**
-     * A simple barcode generation function using default params suitable for usage in pdfs.
-     * Generates the barcodes as base64-encoded png.
-     * @param type Barcode type according to this list: https://github.com/metafloor/bwip-js/wiki/BWIPP-Barcode-Types
-     * @param content Barcode content/text - please remember that some formats only support certain input types.
-     * @returns Barcode image as base64 encoded png string.
-     */
-    public static async generateBarcode(type: string, content: string): Promise<String> {
-        let barcode: Buffer = await bwipjs.toBuffer({
-            bcid: type,
-            text: content,
-            scale: 3,
-            height: 10,
-            includetext: true,
-            textxalign: 'center',
-        });
-        return `data:image/png;base64,${barcode.toString('base64')}`;
-    }
-
     /**
      * Generates a new dummy runner with halfspaces for all strings.
      * Can be used to generate empty sponsoring contracts.