google — jd:/dev/blog

Google Calendar notifications using pynotify

Tue, 03 Jan 2012 00:00:00 GMT

I use Google Calendar to manage my calendars, and I really missed something to warn me whenever I have an appointment with an alert set.

So here is an example of a Python program to do such a thing. It is written using the Google Data APIs Python client library and pynotify.

I'll detail the code here, so you can build your own and adapt it to your needs.

First, we need to import GTK+ and pynotify, and initialize it.

import gtk
import pynotify
pynotify.init(sys.argv[0])

Then, we need to import gdata Calendar API and connect to the calendar. I'll use the simple email/password way to login, which is clearly not the best, but it's also the simplest. Feel free to use OAuth 2.0. :-)

calendar_service = gdata.calendar.service.CalendarService()
calendar_service.email = 'mygooglelogin'
calendar_service.password = 'mygooglepassword'
calendar_service.ProgrammaticLogin()

Now we're ready to request stuff and notify! First, request the events from the default calendar.

feed = calendar_service.GetCalendarEventFeed()

Now we can iterate over feed and do various checks.

for event in feed.entry:
    # If the event status is not confirmed, go to the next event.
    if event.event_status.value != "CONFIRMED":
        continue
    # Now iterate over all the event dates (usually it has one)
    for when in event.when:
        # Parse start and end time
        try:
            start_time = datetime.datetime.strptime(when.start_time.split(".")[0], "%Y-%m-%dT%H:%M:%S")
            end_time = datetime.datetime.strptime(when.end_time.split(".")[0], "%Y-%m-%dT%H:%M:%S")
        except ValueError:
            # ValueError happens on parsing error. Parsing errors
            # usually happen for "all day" events since they have
            # not time, but we do not care about this events.
            continue
        now = datetime.datetime.now()
        # Check that the event hasn't already ended
        if end_time > now:
            # Check each alert
            for reminder in when.reminder:
                # We handle only reminders with method "alert"
                # and whose start time minus the reminder delay has passed
                if reminder.method == "alert" \
                        and start_time - datetime.timedelta(0, 60 * int(reminder.minutes)) < now:
                    # Build the notification
                    notification = pynotify.Notification(summary=event.title.text,
                                                         message=event.content.text)
                    # Set an icon from the GTK+ stock icons
                    notification.set_icon_from_pixbuf(gtk.Label().render_icon(gtk.STOCK_DIALOG_INFO,
                                                                              gtk.ICON_SIZE_LARGE_TOOLBAR))
                    notification.set_timeout(0)
                    # Show the notification
                    notification.show()

Running this program, you should see a notification if an appointment has an alert to be raised at that time.

This should be enough to start to build something.

If you don't want to program this into Python, you might want to take a look at gcalcli.

Google Contacts for Emacs

Mon, 26 Sep 2011 00:00:00 GMT

I finally finished a thing I was really missing: accessing my Google Contacts from Emacs.

That's now possible, thanks to my new google-contacts.el package.

It includes searching for any contact and displaying the result in a window.
You can also jump to a contact from Gnus by pressing a
key, and complete e-mail addresses while composing a mail.

Google Maps for Emacs: moving, caching and home

Mon, 08 Nov 2010 00:00:00 GMT

Last week, I worked on my Google Maps for Emacs extension. I've introduced a new format handling for locations which include the longitude and latitude. The initial format was just a string describing the location, which was obviously too limited.

It now prints coordinates of the different elements when the mouse is over the map, with other information.

It also center the map on M-x google-maps and set a default zoom level. This is something which was not set because it's not a good idea to set center coordinates in order to see all points on the map automatically. But you can still remove the centering by pressing "C". On the other hand, setting it automatically allows to move the map easily, and I think that what most users want to do.

I've also added a "place my home on the map" feature, accessible by pressing h on any map. That adds a marker according to the location set in Emacs using the calendar- variables.

This feature is also available under Org by pressing C-u C-c M-l, which shows the location of your appointment with your home on the map too.

Finally, you also get caching so it does not request images you already seen, which makes the moving nicer and faster to use, and prompt history.

Emacs, Org, whatever the weather!

Wed, 08 Sep 2010 00:00:00 GMT

Another week, another Emacs extension!

I had (once again) a wonderful idea: what if I could have the weather forecasts in my Org agenda? Wouldn't that be wonderful?

My quest started by looking for a service offering a good weather forecast API. I found nothing simple as the hidden Google Weather API, which is nice, but… not documented. Not at all. Not a single line. Nah.

Then, I wrote a google-weather extension, implementing a basic Emacs Lisp API to retrieve data from the Google service:

ELISP> (google-weather-data->forecast (google-weather-get-data "Paris"))
(((9 8 2010)
  (low "53")
  (high "63")
  (icon "http://www.google.com/ig/images/weather/rain.gif")
  (condition "Rain"))
 ((9 9 2010)
  (low "53")
  (high "69")
  (icon "http://www.google.com/ig/images/weather/chance_of_rain.gif")
  (condition "Scattered Showers"))
 ((9 10 2010)
  (low "54")
  (high "72")
  (icon "http://www.google.com/ig/images/weather/partly_cloudy.gif")
  (condition "Partly Cloudy"))
 ((9 11 2010)
  (low "55")
  (high "75")
  (icon "http://www.google.com/ig/images/weather/partly_cloudy.gif")
  (condition "Partly Cloudy")))

My API even implements data caching, which is nice to speed up the agenda display.

By the way, I think my next job will be to hack on the url-cache feature of Emacs, which is utterly buggy and has probably never be used. But that's another topic.

Finally, I just had to write another module on top of that to export the forecasts to Org. A screen shot is probably better than a long and boring explanation, so here's the result.

My only regret is that the icons provided by Google are ugly squares, so I did not want to use them. On the other hand, I did not found any icon set that would have all the icons Google provides (around 20). So I felt back on the icon naming specification to map the Google images to standard images. Any better idea would be welcome, of course.

All the information can be found on the Google Weather for Emacs extension homepage.

Emacs, Google Maps and BBDB

Wed, 18 Aug 2010 00:00:00 GMT

Today's fun idea was to put all my contacts stored into BBDB on a Google Maps' map, using my Google Maps extension for Emacs.

With the help of a few lines of Lisp glue:

(google-maps-static-show
 :markers
 (mapcar
  (lambda (address-entry)
    `((,(concat
         (mapconcat
          'identity
          (elt address-entry 1) ", ") ", "
          (elt address-entry 2) ", "
          (elt address-entry 3) ", "
          (elt address-entry 4) ", "
          (elt address-entry 5)))))
  (mapcan
   (lambda (record)
     ;; We need to copy the returned list, because mapcan will modify it later
     (copy-list (bbdb-record-addresses record)))
   (bbdb-records))))

It's really simplistic, but I did not need more to have fun. :-) This could be extended to set a specific marker and/or color for each contact, with a legend. I'll let that as an exercise for my readers.

M-x google-maps

Mon, 28 Jun 2010 00:00:00 GMT

Since I have started to use Org-mode, I though it was missing something to have appointment locations on a map. Of course, it's easy to get a LOCATION property from an entry, and then browse-url on Google Maps.

But it is too easy for me, so once again I said: challenge accepted! I will bring Google Maps into Emacs!

After several hours of work, the google-maps.el project shows a map!

It fully implements the Google Static Maps API and the Google Maps Geocoding API.

You can type M-x google-maps and type some place to see it marked on map. Of course you can do much more, as seen in the screen shot above.

I've also completed all of this with a small org-location-google-maps.el which simply show a Google Maps' map for the location of an event in Org mode by pressing C-c M-l in an Org buffer or in the Org agenda.