At the Forge - Databases and Calendars
Sure enough, the result of invoking db-calendar.py is a fully iCalendar-compliant file, suitable for importing into Sunbird or any other calendar program. Moreover, simply by modifying the contents of our Events database table, we can ensure that everyone who subscribes to our calendar gets the latest version.
We can go one step further than this, modifying db-calendar.py such that it includes only certain events in its result. For example, perhaps the calendar needs to contain only events in the future; there is no need to clutter someone's calendar (and bandwidth) with events from the past. By adding a simple WHERE clause to our SQL query, we easily can remove all of the events from the past.
More intriguing is the possibility of supporting different groups and access levels to a calendar. HTTP supports authentication with user names and passwords, and although Sunbird doesn't support such protections at the present time, I would expect it (and other programs) to do so in the future. Given that a CGI program easily can determine the user name of the person making an authenticated HTTP request, it's not too far-fetched to say that db-calendar.py could produce different output for different users, depending on a set of assigned permissions or roles.
Finally, although we have focused on iCalendar-format output for the last few months, there isn't any reason why we can turn only the contents of the database into an iCalendar file. Indeed, it's quite possible that we would want to display our events database in plain-old HTML, as well as in iCalendar. Once again, it's easy to see how we could do that using HTML tables—demonstrating once again that relational databases make it easy to display a set of data in a number of different ways.
This month, we have seen how to use a database to store event information that eventually will be transformed into an iCalendar-compliant file. Using a database makes us not only more confident that stored data is valid, but it allows us to create dynamically generated files quickly and easily that are suitable for use in programs that use the iCalendar format.
Resources for this article: /article/8263.
|Natalie Rusk's Scratch Coding Cards (No Starch Press)||Feb 17, 2017|
|Own Your DNS Data||Feb 16, 2017|
|IGEL Universal Desktop Converter||Feb 15, 2017|
|Simple Server Hardening||Feb 14, 2017|
|Server Technology's HDOT Alt-Phase Switched POPS PDU||Feb 13, 2017|
|Bash Shell Script: Building a Better March Madness Bracket||Feb 09, 2017|
- Own Your DNS Data
- Simple Server Hardening
- Understanding Firewalld in Multi-Zone Configurations
- Teradici's Cloud Access Platform: "Plug & Play" Cloud for the Enterprise
- From vs. to + for Microsoft and Linux
- The Weather Outside Is Frightful (Or Is It?)
- Bash Shell Script: Building a Better March Madness Bracket
- IGEL Universal Desktop Converter
- Server Technology's HDOT Alt-Phase Switched POPS PDU
- Natalie Rusk's Scratch Coding Cards (No Starch Press)