Resolved fun issues with promises

ref #3

src/PdfCreator.ts

@@ -1,14 +1,42 @@
 import fs from "fs";
+import pdf_converter from "html-pdf";
 import path from 'path';
-
 /**
  * This class is responsible for all things pdf creation.
  * This uses the html templates from src/templates.
  */
-export class PdFCreator {
+export class PdfCreator {
     private templateDir = path.join(__dirname, '/templates');
 
-    public generateSponsoringContract() {
+    public async generateSponsoringContract(): Promise<any> {
         const template = fs.readFileSync(`${this.templateDir}/sponsoring_contract.html`, 'utf8');
+        let pdf = await pdf_converter.create(template, { format: "A5", orientation: "landscape" });
+        return await this.toBuffer(pdf);
+    }
+
+    /**
+     * Promise wrapper function that resolves the toBuffer promise for pdf generation.
+     * @param pdf The pdf object that shall be turned into a buffer.
+     */
+    public async toBuffer(pdf): Promise<any> {
+        let promise = await new Promise((resolve, reject) => {
+            pdf.toBuffer(function (err, buffer) {
+                resolve(buffer);
+            });
+        });
+        return await promise;
+    }
+
+    /**
+     * Promise wrapper function that resolves the toStream promise for pdf generation.
+     * @param pdf The pdf object that shall be turned into a stream.
+     */
+    public async toStream(pdf): Promise<any> {
+        let promise = await new Promise((resolve, reject) => {
+            pdf.toStream(function (err, stream) {
+                resolve(stream);
+            });
+        });
+        return await promise;
     }
 }