erikrose

def do_stuff(thing):
    config = {
        2: {'message': "Flibbety jibbet!"},
        4: {'message': "A!\nFlibbety jibbet!"},
        5: {'message': "B!\nFlibbety jibbet!"},
        7: {'message': "C!", 'run_funcs': False},
    }
    if thing not in config:
        return
    print config[thing]['message']

erikrose

def do_stuff(thing):
    if thing == 2:
        print "Flibbety jibbet!"
        render_golfclubs()
        sneeze_loudly(True)
        do_other_stuff()
    
    if thing == 4:
        print "A!"
        print "Flibbety jibbet!"

erikrose

from parsimonious import Grammar
from parsimonious.nodes import NodeVisitor


# Adapted from https://raw.github.com/bhyde/css-parser/master/css.peg:
# This is an incredibly inefficient grammar, but it would be simple to
# optimize. Eventually, Parsimonious will know how to do that automatically.
css = Grammar(r"""
    program = S* stylesheet
    digit = ~"[0123456789]"

erikrose

- A sense of scale
    - A Firefox crash is 150K.
    - 50 crashes/second. 3M/day.
    - 110 TB in HDFS
    - 500 GB in PostgreSQL
    - 120 boxes. Real hardware, not VMs.
- Challenges
    - Dictum: “Never lose a crash.”
    - Upside-down user story: few users, much data
    - Hither and thither

erikrose

# Not strictly necessary but should save a lot of RewriteConds and fstats:
RewriteRule ^/search$ - [L]
RewriteRule ^$ - [L]
RewriteRule ^/static($|/.*) - [L]
RewriteRule ^.*/$ - [L]  # Don't muck with the front page or any directory-browing page.

# Append ".html" to files in the tree but not to ones that exist as requested...
RewriteCond /home/vagrant/dxr/tests/test_basic/target/trees%{REQUEST_FILENAME} !-f
# ...and not to folders:
RewriteCond /home/vagrant/dxr/tests/test_basic/target/trees%{REQUEST_FILENAME} !-d

erikrose

@dxr_blueprint.route('/<path:tree_and_path>')
def browse(tree_and_path):
    """Show a directory listing or a single file from one of the trees."""
    tree, _, path = tree_and_path.partition('/')
    tree_folder = os.path.join(current_app.instance_path, 'trees', tree)

    if isdir(os.path.join(tree_folder, path)):
        # It's a bare directory. Add the index file to the end:
        path = os.path.join(path, current_app.config['DIRECTORY_INDEX'])
    else:

erikrose

# First, install everything via vagrant.

# Then...

mkdir ~/bin
cd ~/bin
wget http://pypi.python.org/packages/source/p/python-hglib/python-hglib-0.2.tar.gz
tar -xzf python-hglib-0.2.tar.gz
cd python-hglib-0.2
sudo python setup.py install

erikrose

from collections import deque

from more_itertools import consumer


OPS = {'+': lambda a, b: b + a,
       '/': lambda a, b: b / a,
       '-': lambda a, b: b - a,
       '*': lambda a, b: b * a}

erikrose

Designing a good API is an art, but there are reasons behind the feelings and enumerable rules of thumb that can save costly missteps. Come on an adventure through compactness, orthogonality, consistency, safety, coupling, state handling, layering, and more, illustrated with shining examples (and gruesome mistakes) from popular Python libraries—and walk away with an actionable design plan.

Details

Here's a rough outline that will certainly grow and develop before the actual talk.

• What is an API? Everything is.
• Even if you're not going to expose it publicly, every routine,

erikrose

- [ ] Rising standards of repeatability:
    - [ ] pip freeze
        - [ ] This gives you the basics, defending you against buggy or
              incompatible upstream updates.
        - [ ] Be sure to include dependencies! Install with --no-deps
              and run your test suite to make sure it works.
    - [ ] hashes
        - [ ] This defends you against package replacement (which PyPI
              doesn't allow anymore but other indexes might), indexes
              getting hacked, and MITM attacks. (HTTPS also contributes