A pythonic example of recording metrics about ephemeral scripts with prometheus
In my previous post we talked about how to record information from short lived scripts (I call them ephemeral scripts by the way) with prometheus. The example there was a script which checked the SMART status of each of the disks in a machine and reported that via pushgateway. I now want to work through a slightly more complicated example. I think you hit the limits of reporting simple values in shell scripts via curl requests fairly quickly. For example with the SMART monitoring script, SMART is capable of returning a whole heap of metrics about the performance of a disk, but we boiled that down to a single "health" value. This is largely because writing a parser for all the other values that smartctl returns would be inefficient and fragile in shell. So for this post, we're going to work through an example of how to report a variety of values from a python script. Those values could be the parsed output of smartctl, but to mix things up a bit, I'm going to use a different script I wrote recently. This new script uses the Weather Underground API to lookup weather stations near my house, and then generate…