1. new in this version
2. build a web 2.0 app in happstack
3. why happstack is cool
4. getting started with happstack
5. prerequisites
6. cabal install me
7. first shot at happstack
8. url handling
9. basic HTML inclusion
10. templates
11. stringtemplate basics
12. debugging
13. form data: get and post
14. form data: file uploads
15. cookies
16. introduction to macid
17. first steps with macid
18. scaling with multimaster
19. using macid safely
20. macid dummy data
21. changing the data model
22. macid stress test
23. limitations of macid
24. foreign characters
25. IxSets
26. cron jobs
27. thanks
28. appendix (floundering in ghci)

Start Happstack Automatically At Boot Time

What happens if your Happstack deployment server experiences a power outage?

The way I deal with this issue with a public-facing Happstack application is to have a cron job that runs every minute, that will start the happs application if it isn't running.

thartman@thartman-laptop:~/happs-tutorial>crontab -l
* * * * * /home/thartman/happs-tutorial/happs-tutorial.cron.sh

thartman@thartman-laptop:~/happs-tutorial>cat happs-tutorial.cron.sh
# this is a workaround to a problem that my happs app dies for reasons described at
# http://code.google.com/p/happs/issues/detail?id=40
# generate the executable first by running runServer.sh
# then add this file to your crontab so you have something like
# thartman@thartman-laptop:~>crontab -l
# * * * * * /home/thartman/happs-tutorial/happs-tutorial.cron.sh

if [ -z "`pgrep happs-tutorial`" ];
then cd ~/happs-tutorial
./happs-tutorial >happs-tutorial.cron.out 2>happs-tutorial.cron.err
fi