Creating a Cron Job on Dreamhost

Pre-requisite

The task I wanted to run is a Bash script that runs a bit of Python code, rsync the newly generated data to a github project folder, then do a Git Push

Dreamhost already has virtualenv installed on their ssh shell. And here is a great resource on how to use it for installed the required python packages.

Setting up virtualenv

$ cd project_dir                      # first goes to the project folder
$ virtualenv _myenv                   # this creates the _myenv environment in project_dir
$ source _myenv/bin/activate          # this activate _myenv
$ pip install -r requirement.txt      # this install the py packages you need in _myenv
$ deactivate                          # this deactivate _myenv
$ rm -rf _myenv                       # this delete the virtual environment _myenv

The other pieces

git, python, rsync, and bash are all already available on Dreamhost’s ssh shell.

I just had to do a git clone and run the python code in my project using the _myenv (created above).

Cron Job on Dreamhost

Just follow this awesome article

But to config the Cron Job I need to know what time the Dreamhost server’s on. So in the SSH shell just do $ date. And it seems the server’s on Pacific Standard Time.

And here’s a link that makes converting time between time-zone easy.¹

Also note that Cron Job starts at root, so I found it super helpful by adding a cd command to the directory my python script is first. e.g. in the command to run set it to something like:

cd /path/to/python/script/ && bash script_that_takes_care_of_all.sh