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// This function node combines all of the async values
// reported by the sensor tag node into a single
// payload. The flow will only continue when all values
// have been received.

var payload = context.get('payload') || { data: {} };

// Number of total attributes to report.
// When we collect all attributes from the
// sensor tag, the flow will continue.

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#!/usr/bin/env python
# read CC2650 SensorTag by JP Mens
# follow https://smidgeonpigeon.wordpress.com/2015/07/21/raspberry-pi-2-ble-ti-sensor-tag/
# to get started, but use Sensortag2650.py

import time
import json
import struct
import Sensortag2650 as sensortag
import paho.mqtt.publish as mqtt

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#!/bin/bash

# remove exited containers:
docker ps --filter status=dead --filter status=exited -aq | xargs -r docker rm -v
    
# remove unused images:
docker images --no-trunc | grep '<none>' | awk '{ print $3 }' | xargs -r docker rmi

# remove unused volumes:
find '/var/lib/docker/volumes/' -mindepth 1 -maxdepth 1 -type d | grep -vFf <(

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For this example, I have a very simple Node.js applications that increments a counter stored on Redis. I want to run Redis and the node application independently as I want to have the ability to scale the node application depending on the load. To start off, I have 3 instances of the node server running the application. I have an Nginx server in front of node for load balancing the node instances.

Let’s now talk in terms of containers, specifically Docker containers. Simple; 1 container for each service/process!

• 1 Redis container
• 3 Node containers
• 1 Nginx container So, the overall picture looks something like this:

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Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

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# cleans all images
docker images | awk '{print $3}' | xargs docker rmi 

# cleans all stopped containers
docker rm $(docker ps -q -f status=exited)

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#!/usr/bin/env python

# Run with no args for usage instructions
#
# Notes:
#  - will probably insert duplicate records if you load the same file twice
#  - assumes that the number of fields in the header row is the same
#    as the number of columns in the rest of the file and in the database
#  - assumes the column order is the same in the file and in the database
#

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# following Python packages needs to be installed 
# xlrd, xlsxrd, unidecode, MySQLdb

import xlrd
import xlsxrd
import MySQLdb as mdb
import re
import unidecode

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import csv
import MySQLdb
# open the connection to the MySQL server.
# using MySQLdb
mydb = MySQLdb.connect(host='igor.gold.ac.uk', user='co304so', passwd='*********', db='co304so_LondonCrime')
cursor = mydb.cursor()
csv_data = csv.reader(file('1.csv'))
# execute and insert the csv into the database.
for row in csv_data:
	cursor.execute('INSERT INTO AprilNov2013(Date,Westminster,HACKNEY,Tower_Hamlets)''VALUES(%s, %s, %s, %s)',row)

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# Dockerfile for Node-RED - pulls latest master code from git
# Use the node.js v4 LTS engine
FROM node:4-slim
MAINTAINER ceejay

RUN mkdir -p /root/.node-red
WORKDIR /root/.node-red
 
# download latest stable node-red
RUN npm install -g --unsafe-perm node-red