arnabkaycee

General Guidelines for writing Hyperledger Fabric Chaincodes.

I believe smart-contracts (chaincodes) are the heart of any Blockchain Network. Written correctly can yeild many benefits and truly bring out the best in a secure blockchain network and have distratous effects if written inefficiently. Although I will not discuss about any specific goods and bads of Chaincode design, I will touch down a few guidelines which I experienced while doing some POC applications during my work. Without further ado, let's start.

Below are a few general guidelines / caveats that can be adhered to (although there are exceptions) while writing chaincodes. These I have particularly written for chaincodes written for Hyperledger fabric v.1.0 network in golang. But, I believe they can be extrapolated to chaincodes written in any language for Hyperledger Fabric.

Use Chaincode DevMode

To kickoff your development process, use the DevMode. I cannot emphasise enough, how important it is to use dev mode and save time and eff

fsamin

package main

import (
	"log"
	"os"
	"os/signal"
	"strconv"
	"syscall"

	"github.com/hashicorp/serf/serf"

ghoranyi

This gist will drive you through creating a Docker 1.12 Swarm cluster (with Swarm mode) on AWS infrastructure.

Prerequisites

You need a few things already prepared in order to get started. You need at least Docker 1.12 set up. I was using the stable version of Docker for mac for preparing this guide.

$ docker --version
Docker version 1.12.0, build 8eab29e

You also need Docker machine installed.

conoro

• Install Go for Linux the usual way on your main Linux box:

cd
wget https://storage.googleapis.com/golang/go1.6.2.linux-amd64.tar.gz
tar -zxvf go1.6.2.linux-amd64.tar.gz
sudo mv go /usr/local/
export GOROOT=/usr/local/go
mkdir -p ~/gitwork/go/src
mkdir ~/gitwork/go/bin

xigang

import "regexp"

// Basic regular expressions for validating strings
const (
	Email          string = "^(((([a-zA-Z]|\\d|[!#\\$%&'\\*\\+\\-\\/=\\?\\^_`{\\|}~]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])+(\\.([a-zA-Z]|\\d|[!#\\$%&'\\*\\+\\-\\/=\\?\\^_`{\\|}~]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])+)*)|((\\x22)((((\\x20|\\x09)*(\\x0d\\x0a))?(\\x20|\\x09)+)?(([\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x7f]|\\x21|[\\x23-\\x5b]|[\\x5d-\\x7e]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(\\([\\x01-\\x09\\x0b\\x0c\\x0d-\\x7f]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}]))))*(((\\x20|\\x09)*(\\x0d\\x0a))?(\\x20|\\x09)+)?(\\x22)))@((([a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(([a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])([a-zA-Z]|\\d|-|\\.|_|~|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])*([a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])))\\.)+(([a-zA-Z]|[\\

Lissy93

/**
 * Created by alicia.sykes on 17/07/2015.
 * To run script run "gulp" in the command line
 * To just watch files run "gulp watch"
 * To just clean the public directory run "gulp clean"
 */

/* Include the necessary modules */
var gulp    = require('gulp');
var gutil   = require('gulp-util');      // For logging stats and warnings

gstark

Use tcpdump to monitor mysql

  # Capture the packets
  sudo tcpdump -i eth0 port 3306 -s 65535 -x -n -q -tttt > tcpdump.out

  # analyze all the requests from a given host
  pt-query-digest --type=tcpdump --filter '($event->{host} || $event->{ip} || "") =~ m/192.168.248.64/' tcpdump.out

batok

import paramiko
k = paramiko.RSAKey.from_private_key_file("/Users/whatever/Downloads/mykey.pem")
c = paramiko.SSHClient()
c.set_missing_host_key_policy(paramiko.AutoAddPolicy())
print "connecting"
c.connect( hostname = "www.acme.com", username = "ubuntu", pkey = k )
print "connected"
commands = [ "/home/ubuntu/firstscript.sh", "/home/ubuntu/secondscript.sh" ]
for command in commands:
	print "Executing {}".format( command )