Archive for May 2013

LCFG Client Refactor: host name versus node name

May 23, 2013

A long-standing issue that we have had with the LCFG client is that it is not possible to use an LCFG profile with a name which does not match the host name. They have always been treated by rdxprof and the ngeneric framework as conceptually interchangeable. There is no particular reason for this limitation other […]

python and string encodings

May 21, 2013

I’ve recently finished the User accessible login reports project. After the initial roll-out to users I had a few reports of people getting server errors when certain sets of data were viewed. This website is written in Python and uses the Django framework. During the template processing stage we were getting error messages like the […]

LCFG Client Refactoring: starting the daemon

May 21, 2013

Following on from my previous work on fixing the way in which the UDP socket is opened for receiving notification messages I have been looking at why the LCFG component just hangs when the rdxprof process fails to daemonise. It turns out that the LCFG client component uses an obscure ngeneric feature of the Start […]

LCFG Client Refactor: notification handling

May 21, 2013

One long-standing issue with running the LCFG client (rdxprof) in daemon mode has been that if another process has already acquired the UDP socket which it wants (port 732) then it does not fail at startup but just hangs. This is clearly rather undesirable behaviour as it leaves the machine in an unmanageable state but […]

LCFG Client Refactor: splitting the project

May 14, 2013

I’ve recently been working on splitting the LCFG client code base from the LCFG component which is used to configure and manage the daemon. This allows the client Perl modules to be built in the style of a standard Perl module. The immediate benefit of this is the enhanced portability, it makes it much easier […]

LCFG Client Refactor: Comparing files

May 14, 2013

One thing that we need to do very frequently in the LCFG client, and also in many LCFG components, is comparing files. Typically we want to see if the new file we have just generated is any different from the previous version, in which case we will need to replace old with new and possibly […]

LCFG Client Refactor: New om interface

May 13, 2013

The LCFG client uses the om command line tool to call the configure method for an LCFG component when the resources change. Up until now this has been done using backticks which is not the best approach, particularly given that this involves building a command string and launching a full shell. I’ve now added a […]

LCFG Client Refactor: File and Directory paths

May 9, 2013

The way in which the LCFG client handles paths to files and directories has never been pleasant. The old code contains a lot of hardwired paths inserted at package build-time by CMake using autoconf-style macros (e.g. @FOO@). This makes the code very inflexible, in particular, there is no way for a user to run the […]

LCFG Client Refactor: The joy of tests

May 9, 2013

I’m currently working on stage 8 of my project plan – "Eradicate hard wired paths". I’ll blog about the gory details later but for now I just wanted to show how the small number of tests I already have in place have proved to be very useful. As part of this work I have introduced […]

LCFG Client Refactor: Logging

May 8, 2013

The next stage of untangling the LCFG client code was to improve the logging system. Up till now it has just been done using a set of subroutines which are all declared in the LCFG::Client module. Using the logging code in any other module then requires the loading of that module, this accounts for the […]