codemonitor is a development tool that automatically runs arbitrary commands
when files change on disk and displays the output of the commands graphically.
codemonitor can be used for example to automatically run your tests when you
save a source file.
I have recorded a demo that you can watch here: http://www.youtube.com/watch?v=oucd1p9cjrI&hd=1
codemonitor is written in Haskell and runs on Linux. (The only Linux
dependency though is inotify.)
codemonitor is uploaded to
Hackage
for easy installation. Once you have installed the
Haskell Platform (
yum/apt-get install haskell-platform), you can install codemonitor like
this:
# You need to have gtk installed first. Install it with you package manager
# before you continue. You might need dev libraries as well to be able to
# install the Haskell bindings.
# The install script depends on programs in this directory, so we must
# export it here. It is a good idea to always put this on your path so that
# cabal always refers to the cabal in ~/.cabal/bin.
export PATH="~/.cabal/bin:$PATH"
# Fore some reason, cabal does not install this dependency, so we have to
# install it manually.
cabal install gtk2hs-buildtools
# Then we can install codemonitor.
cabal install codemonitor
After this, codemonitor should be installed in ~/.cabal/bin/codemonitor.
If you have an old version of cabal, you might need to upgrade it. Before you
install codemonitor you need to run this:
# This will install a new cabal in ~/.cabal/bin/, so make sure the path is
# exported when you try to install codemonitor.
cabal install cabal-install
To install a new version of codemonitor, run these commands:
cabal update
cabal install codemonitor
Please contact me if you have trouble installing.
First you need to specify a configuration file that tells codemonitor in
which directory to look for file changes and what commands to run. The
configuration for codemonitor itself looks like this:
.
tests \.hs$ sh run-tests
lint \.hs$ hlint .
The first line is the path to the directory to watch for file changes.
The rest of the lines are specifications of commands. They have the format "{id} {regexp} {executable} {arguments}".
The id must be unique among the commands.
The regexp is used to only run this command if the file that was changed matches the regexp. (Files ending with .hs in the example.)
After the application has been installed, you can run it like this, passing the path to the configuration file:
~/.cabal/bin/codemonitor monitor.config
You can also pass the configuration directly to stdin. It is useful if you only want a single file to run codemonitor. It can look something like this:
#!/bin/sh
~/.cabal/bin/codemonitor <<EOF
.
tests \.hs$ sh run-tests
lint \.hs$ hlint .
EOF
If a file changes while a job is running, a new job is started immediately. The problem is that the old job is not stopped. So you get two jobs running in parallel. That is very problematic when compiling code for example since the parallel jobs touch the same files.
A workaround for this limitation is to create a shell script that runs the command you want to run, and before it does that, it kills the old version of itself. It can be done with a snippet like this:
pidfile=lastpid.txt
if [ -e $pidfile ]; then
kill -9 $(cat $pidfile)
rm $pidfile
fi
echo $$ > $pidfile
... run your command here ...
rm -f $pidfile
Please contact me if you have questions or problems.
