Switched to puppeteer for pdf generation

ref #5

package.json

@@ -45,7 +45,7 @@
     "cors": "^2.8.5",
     "dotenv": "^8.2.0",
     "express": "^4.17.1",
-    "html-pdf": "^2.2.0",
+    "puppeteer": "^7.0.1",
     "reflect-metadata": "^0.1.13",
     "routing-controllers": "^0.9.0-alpha.6",
     "routing-controllers-openapi": "^2.2.0"
@@ -54,6 +54,7 @@
     "@odit/license-exporter": "^0.0.9",
     "@types/express": "^4.17.11",
     "@types/node": "^14.14.22",
+    "@types/puppeteer": "^5.4.3",
     "nodemon": "^2.0.7",
     "release-it": "^14.2.2",
     "rimraf": "^3.0.2",
@@ -73,4 +74,4 @@
       "publish": false
     }
   }
-}
+}

src/PdfCreator.ts

@@ -1,7 +1,6 @@
 import fs from "fs";
-import pdf_converter from "html-pdf";
 import path from 'path';
-import { Stream } from 'stream';
+import puppeteer from "puppeteer";
 
 /**
  * This class is responsible for all things pdf creation.
@@ -9,48 +8,32 @@ import { Stream } from 'stream';
  */
 export class PdfCreator {
     private templateDir = path.join(__dirname, '/templates');
+    private browser;
+
+    constructor() {
+        puppeteer.launch({ headless: true }).then(browser => {
+            this.browser = browser;
+        });
+    }
 
     //TODO: Accept the runner class
-    public async generateSponsoringContract(): Promise<Pdf> {
+    public async generateSponsoringContract(): Promise<any> {
         let template = fs.readFileSync(`${this.templateDir}/sponsoring_contract.html`, 'utf8');
         template = template.replace("{{Runner Name}}", "lelele");
-        return new Pdf(await pdf_converter.create(template, { format: "A5", orientation: "landscape" }));
+        return await this.renderPdf(template, { format: "A5", landscape: true });
-    }
-
-}
-
-/**
- * This class is a wrapper for the pdf objects created by html-pdf.
- * It offers typed conversion to Buffer and Stream.
- */
-export class Pdf {
-    content: any;
-
-    constructor(pdf: any) {
-        this.content = pdf;
     }
 
     /**
-     * Promise wrapper function that resolves the toBuffer promise for pdf generation.
+     * This method manages the creation of pdfs via puppeteer.
+     * @param html The HTML that should get rendered.
+     * @param options Puppeteer PDF option (eg: {format: "A4"})
      */
-    public async toBuffer(): Promise<Buffer> {
+    public async renderPdf(html: string, options): Promise<any> {
-        let promise = await new Promise<Buffer>((resolve, reject) => {
+        const page = await this.browser.newPage();
-            this.content.toBuffer(function (err, buffer: Buffer) {
+        await page.setContent(html);
-                resolve(buffer);
+        const pdf = await page.pdf(options);
-            });
+        await page.close();
-        });
+        return pdf;
-        return await promise;
     }
 
-    /**
-     * Promise wrapper function that resolves the toStream promise for pdf generation.
-     */
-    public async toStream(): Promise<Stream> {
-        let promise = await new Promise<Stream>((resolve, reject) => {
-            this.content.toStream(function (err, stream: Stream) {
-                resolve(stream);
-            });
-        });
-        return await promise;
-    }
 }

src/controllers/PdfController.ts

@@ -15,6 +15,6 @@ export class PdfController {
     async generateContracts() {
         //TODO: Accept the real classes
         const contracts = await this.pdf.generateSponsoringContract();
-        return await contracts.toBuffer();
+        return await contracts;
     }
 }