Experimental: Support PDF rendering

proto/rendererv2.proto

@@ -19,6 +19,7 @@ message RenderRequest {
   string timezone = 9;
   map<string, StringList> headers = 10;
   string authToken = 11;
+  string encoding = 12;
 }
 
 message RenderResponse {

src/browser/browser.ts

@@ -9,6 +9,7 @@
 import { Logger } from '../logger';
 import { RenderingConfig } from '../config/rendering';
 import { ImageRenderOptions, RenderOptions } from '../types';
+import { getPDFOptionsFromURL } from './pdf';
 
 export interface Metrics {
   durationHistogram: promClient.Histogram;
@@ -319,6 +320,7 @@
       }
     }
 
+    const isPDF = options.encoding === 'pdf';
     try {
       await this.withTimingMetrics(() => {
         if (this.config.verboseLogging) {
@@ -357,15 +359,15 @@
           {
             timeout: options.timeout * 1000,
           },
-          options.fullPageImage || false
+          options.fullPageImage || isPDF
         );
       }, 'panelsRendered');
     } catch (err) {
       this.log.error('Error while waiting for the panels to load', 'url', options.url, 'err', err.stack);
     }
 
     if (!options.filePath) {
-      options.filePath = uniqueFilename(os.tmpdir()) + '.png';
+      options.filePath = uniqueFilename(os.tmpdir()) + (isPDF ? '.pdf' : '.png');
     }
 
     await this.setPageZoomLevel(page, this.config.pageZoomLevel);
@@ -381,10 +383,26 @@
           height: scrollResult.scrollHeight,
         });
       }
+
+      if (isPDF) {
+        const scale = parseFloat((options.deviceScaleFactor as string) || '1') || 1;
+        return page.pdf({
+          ...getPDFOptionsFromURL(options.url),
+          margin: {
+            bottom: 0,
+            top: 0,
+            right: 0,
+            left: 0,
+          },
+          path: options.filePath,
+          scale: 1/scale,
+        })
+      }
+
       return page.screenshot({ path: options.filePath, fullPage: options.fullPageImage, captureBeyondViewport: options.fullPageImage || false });
     }, 'screenshot');
 
-    if (options.scaleImage) {
+    if (options.scaleImage && !isPDF) {
       const scaled = `${options.filePath}_${Date.now()}_scaled.png`;
       const w = +options.width / options.scaleImage;
       const h = +options.height / options.scaleImage;

src/browser/pdf.ts

@@ -0,0 +1,13 @@
+import * as puppeteer from 'puppeteer';
+
+// Allow setting the more esoteric PDF options via URL parameters 
+export function getPDFOptionsFromURL(url: string): puppeteer.PDFOptions {
+  const urlParams = new URLSearchParams(url);
+  return {
+    landscape: urlParams.get('pdf.landscape') !== 'false', // defaults true
+    format: (urlParams.get('pdf.format') as puppeteer.PaperFormat) ?? 'A4',
+    omitBackground: urlParams.get('pdf.omitBackground') === 'true', // defaults false,
+    printBackground: urlParams.get('pdf.printBackground') !== 'false',  // defaults true,
+    pageRanges: urlParams.get('pdf.pageRanges') ?? undefined,
+  };
+}

src/plugin/v2/grpc_plugin.ts

@@ -135,6 +135,7 @@ class PluginGRPCServer {
       timezone: req.timezone,
       deviceScaleFactor: req.deviceScaleFactor,
       headers: headers,
+      encoding: req.encoding,
     };
 
     this.log.debug('Render request received', 'url', options.url);

src/plugin/v2/types.ts

@@ -18,6 +18,7 @@ export interface RenderRequest {
     [header: string]: StringList;
   };
   authToken: string;
+  encoding: string;
 }
 
 export interface RenderResponse {