PrintingPageToPdf.java

package com.github.kklisura.cdt.examples;

/*-
 * #%L
 * cdt-examples
 * %%
 * Copyright (C) 2018 - 2021 Kenan Klisura
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */

import com.github.kklisura.cdt.launch.ChromeLauncher;
import com.github.kklisura.cdt.protocol.commands.Page;
import com.github.kklisura.cdt.protocol.types.page.PrintToPDF;
import com.github.kklisura.cdt.protocol.types.page.PrintToPDFTransferMode;
import com.github.kklisura.cdt.services.ChromeDevToolsService;
import com.github.kklisura.cdt.services.ChromeService;
import com.github.kklisura.cdt.services.types.ChromeTab;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Base64;

/**
 * The following example opens the HackerNews and prints its page to PDF. PDF printing is supported
 * on chrome headless at the moment.
 *
 * @author Kenan Klisura
 */
public class PrintingPageToPdf {
  public static void main(String[] args) {
    // Create chrome launcher.
    final ChromeLauncher launcher = new ChromeLauncher();

    // Launch chrome either as headless (true) - PDF printing is only supported on Chrome headless
    // at the moment
    final ChromeService chromeService = launcher.launch(true);

    // Create empty tab ie about:blank.
    final ChromeTab tab = chromeService.createTab();

    // Get DevTools service to this tab
    final ChromeDevToolsService devToolsService = chromeService.createDevToolsService(tab);

    // Get individual commands
    final Page page = devToolsService.getPage();
    page.enable();

    // Navigate to github.com.
    page.navigate("https://news.ycombinator.com/");

    page.onLoadEventFired(
        loadEventFired -> {
          System.out.println("Printing to PDF...");

          final String outputFilename = "test.pdf";

          Boolean landscape = false;
          Boolean displayHeaderFooter = false;
          Boolean printBackground = false;
          Double scale = 1d;
          Double paperWidth = 8.27d; // A4 paper format
          Double paperHeight = 11.7d; // A4 paper format
          Double marginTop = 0d;
          Double marginBottom = 0d;
          Double marginLeft = 0d;
          Double marginRight = 0d;
          String pageRanges = "";
          Boolean ignoreInvalidPageRanges = false;
          String headerTemplate = "";
          String footerTemplate = "";
          Boolean preferCSSPageSize = false;
          PrintToPDFTransferMode mode = PrintToPDFTransferMode.RETURN_AS_BASE_64;

          dump(
              outputFilename,
              devToolsService
                  .getPage()
                  .printToPDF(
                      landscape,
                      displayHeaderFooter,
                      printBackground,
                      scale,
                      paperWidth,
                      paperHeight,
                      marginTop,
                      marginBottom,
                      marginLeft,
                      marginRight,
                      pageRanges,
                      ignoreInvalidPageRanges,
                      headerTemplate,
                      footerTemplate,
                      preferCSSPageSize,
                      mode));

          System.out.println("Done!");
          devToolsService.close();
        });

    devToolsService.waitUntilClosed();
  }

  private static void dump(String fileName, PrintToPDF printToPDF) {
    FileOutputStream fileOutputStream = null;
    try {
      File file = new File(fileName);
      fileOutputStream = new FileOutputStream(file);
      fileOutputStream.write(Base64.getDecoder().decode(printToPDF.getData()));
    } catch (IOException e) {
      e.printStackTrace();
    } finally {
      if (fileOutputStream != null) {
        try {
          fileOutputStream.flush();
          fileOutputStream.close();
        } catch (IOException e) {
          e.printStackTrace();
        }
      }
    }
  }
}