How to open a html file available in local machine in selenium grid node - selenium

Question

I have a html file in my local machine. When running my selenium-java code locally through eclipse, I can access the html file through the code mentioned below -
File file = new File(url);
driver.get("file:///" + file.getAbsolutePath());
If I run the code through selenium grid, registered node doesn't pick up the html file path to be opened in chrome since the absolute path points to the local machine.
Is there any solution available to open the locally available html file through selenium grid-node?

Answer 1

You should use a LocalFileDetector.
import org.openqa.selenium.remote.LocalFileDetector
import org.openqa.selenium.remote.RemoteWebDriver
WebDriver driver = new RemoteWebDriver(new URL("http://localhost:4444/wd/hub"), DesiredCapabilities.firefox());
driver.setFileDetector(new LocalFileDetector())
Your upload should now work.

Answer 2

There are basically two ways in which you can get this done. I will list out both the approaches. Please feel free to pick and choose whichever works for you.
Using custom node servlet
You need to follow the below steps:
Create a new custom servlet, using which you can upload a file using a HTTP POST method.
It could look something like below [ This code is borrowed from a journaldev post here and being included here only for the sake of completeness] You may need to tweak the code before use and not necessarily use it as is. The current code returns a html response, but you may need to change it so that it returns a JSON response which contains the actual path where the file was uploaded to. This path is what you will use in your driver.get() call.
package com.journaldev.servlet;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
public class UploadDownloadFileServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private ServletFileUpload uploader = null;
#Override
public void init() throws ServletException{
DiskFileItemFactory fileFactory = new DiskFileItemFactory();
File filesDir = (File) getServletContext().getAttribute("FILES_DIR_FILE");
fileFactory.setRepository(filesDir);
this.uploader = new ServletFileUpload(fileFactory);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String fileName = request.getParameter("fileName");
if(fileName == null || fileName.equals("")){
throw new ServletException("File Name can't be null or empty");
}
File file = new File(request.getServletContext().getAttribute("FILES_DIR")+File.separator+fileName);
if(!file.exists()){
throw new ServletException("File doesn't exists on server.");
}
System.out.println("File location on server::"+file.getAbsolutePath());
ServletContext ctx = getServletContext();
InputStream fis = new FileInputStream(file);
String mimeType = ctx.getMimeType(file.getAbsolutePath());
response.setContentType(mimeType != null? mimeType:"application/octet-stream");
response.setContentLength((int) file.length());
response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
ServletOutputStream os = response.getOutputStream();
byte[] bufferData = new byte[1024];
int read=0;
while((read = fis.read(bufferData))!= -1){
os.write(bufferData, 0, read);
}
os.flush();
os.close();
fis.close();
System.out.println("File downloaded at client successfully");
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
if(!ServletFileUpload.isMultipartContent(request)){
throw new ServletException("Content type is not multipart/form-data");
}
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.write("<html><head></head><body>");
try {
List<FileItem> fileItemsList = uploader.parseRequest(request);
Iterator<FileItem> fileItemsIterator = fileItemsList.iterator();
while(fileItemsIterator.hasNext()){
FileItem fileItem = fileItemsIterator.next();
System.out.println("FieldName="+fileItem.getFieldName());
System.out.println("FileName="+fileItem.getName());
System.out.println("ContentType="+fileItem.getContentType());
System.out.println("Size in bytes="+fileItem.getSize());
File file = new File(request.getServletContext().getAttribute("FILES_DIR")+File.separator+fileItem.getName());
System.out.println("Absolute Path at server="+file.getAbsolutePath());
fileItem.write(file);
out.write("File "+fileItem.getName()+ " uploaded successfully.");
out.write("<br>");
out.write("Download "+fileItem.getName()+"");
}
} catch (FileUploadException e) {
out.write("Exception in uploading file.");
} catch (Exception e) {
out.write("Exception in uploading file.");
}
out.write("</body></html>");
}
}
Create a sample project, which includes a dependency on the selenium libraries and which contains the servlet built in step (1) and create a jar out of it. For instructions on how to do all of this, you can refer to my blog post here (or) to the official selenium documentation here.
Start the node, along with the -servlets parameter so that your newly created node servlet, gets injected into the node and is available via http://<Node_IP_Address>:<Node_Port>/extra/UploadDownloadFileServlet (since our sample servlet's name was UploadDownloadFileServlet)
Now in your test code, you can create a new RemoteWebDriver instance as always.
You now need to upload your html file to the remote node where the new session was created. For doing that, you need to know the IP of the node where your test ran. So you make use of a library such as talk2grid (I built this library) or leverage the approach of determining this information on your own by referring to my blog here
Once you have the IP and port, you now trigger a HTTP POST to the servlet you created earlier by hitting the endpoint http://<Node_IP_Address>:<Node_Port>/extra/UploadDownloadFileServlet and get back the path to where it was uploaded in the response.
Now use the path that was returned in step (6) in your driver.get() call (don't forget to include the file:/// protocol)
That should do.
Using Javascript
In this approach, you basically start off by loading a blank page (for e.g., driver.get("about:blank"); and then make use of Javascript to start dynamically creating your web page via document.createElement() call (Refer to this article for more information ) and create the entire page. You can now start interacting with the page.
Approach (1) would be useful only when you are working with a grid environment wherein you are allowed to add servlets etc and access its IP and port.
Approach (2) will work in all use cases including third party remote execution environment providers such as SauceLabs or BrowserStack (In case you use them as well)