Monday, 5 May 2014

Making the Raspberry Pi Email IP on Boot

I needed my Raspberry Pi to email its IP address to me when it booted in order to ease finding the IP address when running headless.  Here's how I did it:

  1. There are some really good instructions here:
  2. In order for it to work I had to set up an application password for gmail since I'm using two-factor authentication to login
  3. Reboot and it sent me an email.  That was painless!

Twilio Interface for the Rube Goldberg Machine

Here's how I built the Twilio interface to the Rube Goldberg machine...

  1. Install the Twilio python libraries: sudo pip install twilio
  2. Set up a feature branch for Twilio: git checkout -b twilio-plugin
  3. Set up tests and code to load credentials from twilio.secret file
  4. From the secret file load the account_sid and auth_token
  5. Write the update_state() method to send an SMS with Twilio
  6. Decided not to unittest the SMS sending as this is just simple interface code with no logic
  7. Used the python code documented at:
  8. With a bit of Blu Tack, and some dominoes the system worked:

Sunday, 4 May 2014

Fixing Anki Flashcard Dates

I've been using Anki for a while to learn things.  Recently I made the mistake of editing some existing cards to have a new meaning.  The problem was that the algorithm for when the card would be next presented to me did not reset itself on the edit.  I was left wanting to see the edited card, but Anki telling me that I'd have to wait for three months first.

Here's how I fixed it:

  1. Installed the full PC version of Anki:  sudo apt-get install anki
  2. Connect the full PC version and sync up the deck in question
  3. Realise that the Debian stable version of Anki is out of date to work with the server
  4. Set up Apt-Pinning for Anki:
    1. Add a testing entry to /etc/apt/sources.list
    2. Edit /etc/apt/preferences and set it up like this
    3. Package: *
      Pin: release a=stable
      Pin-Priority: 900
      Package: *
      Pin: release a=testing
      Pin-Priority: 600
    4. Run aptitude, update
    5. Find the anki package in the aptitude UI
    6. Pick the 2.0... version of Anki and install it -- being careful to make sure aptitude picks the correct version
  5. With the PC client running click "browse"
  6. Select the required deck
  7. Select all the cards
  8. Do Edit->Reschedule then set the schedule for zero days
  9. Close the browser and reopen the deck, all the cards are now ready for review
  10. Sync back up to the server and back down the phone again