Alembic Cheat Sheet - Python/SQLAlchemy

alembic revision --autogenerate -m "<your message>"
alembic upgrade head

Problem: FAILED: Target database is not up to date.
Solution: alembic upgrade head

Problem: No such revision '5000106def16'
Solution:

1. sqlite3 db.sqlite3
2. drop table alembic_version; (and exit, ctrl+d)
3. alembic upgrade head

Failed to fetch http://security.ubuntu.com

W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/quantal-security/main/binary-amd64/Packages 404 Not Found [IP: 91.189.91.14 80]

This is happening because you’re on an unsupported/old version of Ubuntu.

One way to fix it:

1. nano /etc/apt/sources.list
2. Change all entries referring to http://archive.ubuntu.com/ubuntu to http://old-releases.ubuntu.com/ubuntu

Best Python Tricks

https://gist.github.com/JeffPaine/6213790

Most of the examples involve making your code much faster by using iterators instead of creating copies of the data. Example: xrange

Here’s the video: https://www.youtube.com/watch?v=OSGv2VnC0go

CSS Selectors - ~ + >

http://css-tricks.com/child-and-sibling-selectors/

That’s an excellent article describing what angle brackets, plus signs, and tildes do in CSS selectors. The illustrations make it especially clear.

Change Percent To Numbers and Keep Color - Flot Pie Chart

You can access the color of the section of the pie chart by using “series.color”:

Use List In Bind Parameters - SQLAlchemy

Overwriting module with same version in Heroku - Python

I needed to install a newer version of a module from a github commit, but it had the same version number. Heroku just used the cached version of the module and didn’t overwrite it with the newer version.

The easiest fix for this:

1. Create a file in your application’s root directory called runtime.txt with only “python-3.4.1” written inside.
2. Add, commit, and push the new runtime.txt
3. Change runtime.txt back to “python-2.7.6”
4. Add, commit, and push to clear your virtualenv and reinstall all modules

The server quit without updating PID file (/var/run/mysqld/mysqld.pid). - MySQL

. * The server quit without updating PID file (/var/run/mysqld/mysqld.pid).

If you’re getting this error message, try using sudo to start mysql.

Submit Form When User Clicks Option (autosubmit) - Typeahead.js

http://stackoverflow.com/a/18483816/1364191

The bolded section below will automatically submit your form when you select an option from the Typeahead.js dropdown:

$('#remote .typeahead').typeahead(null, {
    displayKey: 'value',
    source: site_search.ttAdapter()
}).on('typeahead:selected', function(e){
      e.target.form.submit();
    });

Using Enter Key With Typeahead.js - Javascript

https://github.com/twitter/typeahead.js/issues/255

If your text input with typeahead.js is not letting you use the enter key, you need to add a submit button (if you don’t already have one).

You can hide it if you want:

<input type="submit" value="Submit" style="display: none">