I realised I had an ical file of all my appointments from the period I used Google Calendar from January 2008 when I started as an independent consultant, until February 2020 when I switched to the calendar in my company’s NextCloud.
I never search through that file even though I sometimes wonder what I did at a certain moment in that period. After a nudge by Martijn Aslander who wrote on a community platform we both frequent about back filling his daily activities into Obisidian for instance based on his photos of a day through the years in his archive, I thought to import that ical file and turn it into day logs listing my appointments for a date.
I tried to find some ready made parsers or libraries I could use in PHP, but most I could find is aimed at importing a live calendar rather than an archived file, and none of them were aimed at creating an output of that file in a different format. Looking at the ical file I realised that making my own simple parser should be easy enough.
I write a small PHP script that reads the ical file line by line until it finds one that says
BEGIN:VEVENT. Then it reads the lines until it finds the closing line
END:VEVENT. It then interprets the information between those lines, lifting out the date, location, name and description, while ignoring any other information.
After each event it finds, it writes to a file ‘Daylog [date].md’ in a folder ./year/month (creating the file or appending the event as a new line if the file exists). It uses the format I use for my current Day logs.
Let it repeat until it processed all 4.714 events in my calendar from 2008 to 2020.
Screenshot of the newly created Daylog for 20 February 2008, based on the appointments I had that day, taken from the calendar archive. This one mentions a preparatory meeting for the open GovCamp I helped organise that year in June, which kicked off my work in open data since then.