keenhenry

The use of __main__.py to create executables

myprojectfolder/
    |_ __main__.py
    |_ __init__.py

Being __main__.py:

print("Hello")

keenhenry

git ls-files -z | xargs -0n1 git blame -w | perl -n -e '/^.*\((.*?)\s*[\d]{4}/; print $1,"\n"' | sort -f | uniq -c | sort -n

keenhenry

Requirements

• no upfront installation/agents on remote/slave machines - ssh should be enough
• application components should use third-party software, e.g. HDFS, Spark's cluster, deployed separately
• configuration templating
• environment requires/asserts, i.e. we need a JVM in a given version before doing deployment
• deployment process run from Jenkins

Solution

keenhenry

Here are seven JavaScript concepts you must understand before you go into your next JavaScript job interview:

1. Prototypes - JavaScript is a prototype-based language. Even more, it's a delegation-based system, which means that each object has a prototype chain. When you try to access a property on an object, and that property is not found, JavaScript looks at the object's prototype. The prototype is a delegate object, which means that the property lookup is delegated to the prototype object. That object, in turn, may have its own prototype. The search continues up the prototype chain until it reaches the root prototype, which is usually Object.prototype. The best feature of this system is that many object instances can share the same methods on a prototype object, which conserves memory and enables easy code reuse. To assign a prototype to a new object, you can use Object.create(prototypeObject). Prototypal OO is the first course being offered in the "Learn JavaScript" series.

2. Functional Programming

keenhenry

#!/usr/bin/env python

class Node(object):

    __slots__ = ('letters', 'children', 'num_occurs')

    def __init__(self, letters=None):

        self.letters = letters # only leaf nodes have non-None letters
        self.children = {}

keenhenry

#! /bin/sh
### BEGIN INIT INFO
# Provides:          supervisord
# Required-Start:    $remote_fs
# Required-Stop:     $remote_fs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Example initscript
# Description:       This file should be used to construct scripts to be
#                    placed in /etc/init.d.

keenhenry

# supervisord - Upstarts the supervisor as service
# Put this file into /etc/init/supervisord.conf
#   sudo service supervisord start
#   sudo service supervisord stop
# Service gets started as root
# Needs `pgrep` available to root

description "Supervisord - Upstart"

stop on runlevel [016]

keenhenry

import shutil
import tempfile

from django.conf import settings
from django.core.files.storage import FileSystemStorage
from django.db.models import FileField
from django.db.models.loading import get_model, get_models
from django.test.runner import DiscoverRunner

keenhenry

PyCon 2012 Digest

from DevOps team {rduplain,mattd,teebes}, to mobile developers at WillowTree Apps

Pronunciation

keenhenry

While attempting to explain JavaScript's reduce method on arrays, conceptually, I came up with the following - hopefully it's helpful; happy to tweak it if anyone has suggestions.

Intro

JavaScript Arrays have lots of built in methods on their prototype. Some of them mutate - ie, they change the underlying array in-place. Luckily, most of them do not - they instead return an entirely distinct array. Since arrays are conceptually a contiguous list of items, it helps code clarity and maintainability a lot to be able to operate on them in a "functional" way. (I'll also insist on referring to an array as a "list" - although in some languages, List is a native data type, in JS and this post, I'm referring to the concept. Everywhere I use the word "list" you can assume I'm talking about a JS Array) This means, to perform a single operation on the list as a whole ("atomically"), and to return a new list - thus making it much simpler to think about both the old list and the new one, what they contain, and