Set Firefox profile to download files automatically using Selenium and Java

Question

I want to verify file download using Selenium WebDriver and Java. The file to download is of PDF format. When WebDriver clicks on "Download" link in the AUT, Firefox opens up the following download confirmation window:

I want Firefox to download the file automatically without showing above confirmation window, so I used the below code:

FirefoxProfile firefoxProfile=new FirefoxProfile();
firefoxProfile.setPreference("browser.download.folderList",2);
firefoxProfile.setPreference("browser.download.manager.showWhenStarting",false);
firefoxProfile.setPreference("browser.download.dir",downloadPath);
firefoxProfile.setPreference("browser.helperApps.neverAsk.saveToDisk","application/pdf");
WebDriver driver=new FirefoxDriver(firefoxProfile); 

but still Firefox shows the same window. How can I set Firefox profile so that PDF files are downloaded automatically without showing the confirmation dialogue?

Answer 1

Just like @Jason suggested, it's most probably another mime type. To get the mime type:

• Open Developer Tools
• Go to Network
• Click on the link to download the pdf
• In the network panel, select the first request
• The mime type is the Content-Type from the response header:

Then to download a PDF with Firefox:

FirefoxOptions options = new FirefoxOptions();
options.setPreference("browser.download.folderList", 2);
options.setPreference("browser.download.dir", "C:\Windows\temp");
options.setPreference("browser.download.useDownloadDir", true);
options.setPreference("browser.download.viewableInternally.enabledTypes", "");
options.setPreference("browser.helperApps.neverAsk.saveToDisk", "application/pdf;text/plain;application/text;text/xml;application/xml");
options.setPreference("pdfjs.disabled", true);  // disable the built-in PDF viewer

WebDriver driver = new FirefoxDriver(options);
driver.get("https://www.mozilla.org/en-US/foundation/documents");
driver.findElement(By.linkText("IRS Form 872-C")).click();