dineshsprabu

Docker commands

Creating building docker image. Create Dockerfile with below content. Run docker build -t <image-name> .

FROM steveny/predictionio
CMD ["python", "app.py"]
EXPOSE 8000

Running a docker with image. -i opens interactive shell.

dineshsprabu

Useful Postgres Commands

Listing users

\du

Creating new user(ROLE)

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class Handler(tornado.web.RequestHandler):
  def args_to_dict(self):
    """ This method converts request arguments to
    usable dict 
    """
    params = self.request.arguments
    for k,v in params.items():
        params[k] = v[0].decode("utf-8")
    return params

dineshsprabu

Useful Unix/Linux Commands for Big Data

Line count from a file or multiple files or any other stream.

cat input/*.csv | wc -l

Finding a particular string across files, on a directory.

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App Structure for Tornado with multiple handlers and a global Thread pool between handlers

dir: handlers

# a_hander.py

from lib import global_for_handlers

def get_thread_pool():

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How to use supervisor to run a program as daemon?

Install the supervisor package

sudo apt-get install supervisor

Create a config file for your daemon at /etc/supervisor/conf.d/flashpolicyd.conf

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var AppStorage = function(select){
	var self = this;
	self.storageObject = chrome.storage.local;

	if(select && select.settings && chrome.storage && chrome.storage.sync){
		self.storageObject = chrome.storage.sync;
	}

	self.get = function(key){
		return new Promise(function(resolve, reject){

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Get current tab URL

Add below to permissions on manifest

"permissions": [
    "tabs",
 "http://*/*", 

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from concurrent import futures
import requests

def get_data(url):
	if url == 0:
		return "working"
	return requests.get(url).text

# Running a blocking task on executor.
# Increasing ThreadPool size or setting it to None, 

dineshsprabu

Creates a local chef cookbook on the current dir.
  chef generate cookbook nodejs-install .

Running a chef script local
  chef-client --local-mode <receipe-name>.rb