bzamecnik

#!/usr/bin/env groovy

/*

Generates a template for journal (for a single month).

Example:

 Journal 2013/11

bzamecnik

bzamecnik

def gandalf(func):
  def inner(*args, **kwargs):
    raise ValueError("You shall not pass!")
    return func(*args, **kwargs)
  return inner

@gandalf
def balrog():
  pass

bzamecnik

#!/usr/bin/env python
# ByteBeats - byte-level procedural music
#
# Source: Jamey at Royal Paw
# http://royal-paw.com/2012/01/bytebeats-in-c-and-python-generative-symphonies-from-extremely-small-programs/
#
# Adapted to run in a single script.
#
# run as:
# $ python bytebeats.py 0 | sox -r 8000 -b 8 -c 1 -t raw -e signed-integer - -d

bzamecnik

import socket

def netcat(hostname, port):
    """
    Reads lines from a network socket and prints them to standard output.
    Similar to: netcat $HOST $PORT.
    """
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((hostname, port))
    socket_file = s.makefile()

bzamecnik

import zmq
import time

context = zmq.Context()
socket = context.socket(zmq.PUB)
socket.connect("tcp://127.0.0.1:5556")

# Sleep a bit of time until the connection is properly established,
# otherwise some messages may be lost.
# http://stackoverflow.com/questions/7470472/lost-messages-on-zeromq-pub-sub

bzamecnik

# https://spark.apache.org/downloads.html
# https://spark.apache.org/docs/latest/

# download
wget http://d3kbcqa49mib13.cloudfront.net/spark-2.0.0-bin-hadoop2.7.tgz

# verify the checksum
curl http://www.apache.org/dist/spark/spark-2.0.0/spark-2.0.0-bin-hadoop2.7.tgz.md5
md5sum spark-2.0.0-bin-hadoop2.7.tgz

bzamecnik

// run eg. in spark-shell...

// uncompressed CSV without a header
val df = spark.read.csv("input.csv")
df.write.format("parquet").save("output.parquet")

// it produces a directory output.parquet/ with the following content:
//
// ls -l output.parquet/
// -rw-r--r-- 1 bza bza 146346 Sep 29 16:06 part-r-00000-8a89541d-9071-4246-b525-22e894ef3e0b.snappy.parquet

bzamecnik

Connecting as the admin:

$ sudo -u postgres psql

Creating a new user:

postgres=# CREATE ROLE foouser WITH LOGIN PASSWORD '************';

bzamecnik

Anaconda Python script running as systemd service

This way a Python daemon can be installed on Rasbian, Ubuntu or similar systems using systemd.

Installing:

sudo cp hello.service /lib/systemd/system/hello.service
sudo systemctl daemon-reload
sudo systemctl enable hello.service