Thursday, November 5, 2015

VMWare Shared Folders oin Fedora 23


if you haven't noticed: Fedora 23 is out, and its time to get your hands wet on it. Being forced to use a Windows Laptop, I am typically doing this by installing a VMware guest. Once the virtual machine is up, the first thing i want to do is accessing my Windows home directory. The easiest way to do this is by creating a so-called "Shared Folder" in the VMware settings for my machine. On the guest, you need to install the "VMware Tools" and do something like

mkdir /home/username/sharedfolder
sudo mount -t vmhgfs -o uid=1000,gid=1000 .host:sharename /home/username/sharedfolder

(The options uid=1000,gid=1000 ensure, that the mounted directory is readable, and writable for the user with uid=1000, and gid=1000, which is me.)

The problem with that procedure is, that it depends on a kernel module called "hgfs", which must be installed as part of the "VMware Tools". And, needless to say: Installation of the VMware Tools (version 9.2.0-799703, as of this writing) fails, because the Kernel isn't compatible to the sources distributed by VMware.

So far, the only reasonable solution was to wait for an updated tools version by VMware. (I generally ignored the possibility to patch those distributed sources as overly complicated, and insecure. However, there's a new, and better solution available:

Fedora 23 automatically installs an RPM named open-vm-tools. And this includes two programs, that allow use of shared folders without the kernel module:

  # Display a list of all shared folders:
  # Note, that it includes a share called "sharedfolder".
  $ vmware-hgfsclient sharedfolder

  # Create a directory named /home/username/foo, and mount the shared folder there.
  $ vmhgfs-fuse .host:foo /home/username/sharedfolder
  $ cd /home/username/sharedfolder
  $ touch testfile
  $ rm testfile

Note, that neither "sudo" nor the specification of any options was required.

So, in other words: As of Fedora 23, the VMware Tools are no longer required. Mouse integration, Cut and Paste, and using shared folders: Everything works out of the box. (I can live without the thin print drivers.)

Tuesday, March 17, 2015

Honouring Terry Pratchett: Java Web Application

This Blogs name is Grumpy Apache. These days, there are excellent reasons, for being grumpy: After all, my favourite author Terry Pratchett has died, way too early. But, as Terry wrote in Going Postal about John Dearheart:

His name, however, continues to be sent in the so-called Overhead of the clacks. The full message is "GNU John Dearheart", where the G means, that the message should be passed on, the N means "Not Logged" and the U that it should be turned around at the end of the line. So as the name "John Dearheart" keeps going up and down the line, this tradition applies a kind of immortality as "a man is not dead while his name is still spoken".
This means, we'll be celebrating "Being childish day" today, by adding the HTTP Header

      X-Clacks-Overhead: GNU Terry Pratchett

to our web sites. And, here's how to do that with any Java Web Application.

Its simple. First of all, you'll be adding this class to your web application. It is a so-called servlet filter. I'll quote the relevant method here:

public void doFilter(ServletRequest pReq, ServletResponse pRes,
                                         FilterChain pChain) throws IOException,
ServletException {
if (pRes instanceof HttpServletResponse) {
final HttpServletResponse res = (HttpServletResponse) pRes;
res.addHeader("X-Clacks-Overhead", "GNU-Terry-Pratchett");
pChain.doFilter(pReq, pRes);
Besides, add the following snippets to your web.xml:


And, that's it! No modification of servlets, or the like, just a simple addition, that you can make to any web application.

Keep in mind:

As long as we are shifting his name on the Internet, Terry isn't dead.