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@bradmontgomery
bradmontgomery / dummy-web-server.py
Last active June 11, 2024 08:36
a minimal http server in python. Responds to GET, HEAD, POST requests, but will fail on anything else.
#!/usr/bin/env python
"""
Very simple HTTP server in python (Updated for Python 3.7)
Usage:
./dummy-web-server.py -h
./dummy-web-server.py -l localhost -p 8000
Send a GET request:
@earthgecko
earthgecko / bash.generate.random.alphanumeric.string.sh
Last active July 4, 2024 17:31
shell/bash generate random alphanumeric string
#!/bin/bash
# bash generate random alphanumeric string
#
# bash generate random 32 character alphanumeric string (upper and lowercase) and
NEW_UUID=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 32 | head -n 1)
# bash generate random 32 character alphanumeric string (lowercase only)
cat /dev/urandom | tr -dc 'a-z0-9' | fold -w 32 | head -n 1
@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = git@github.com:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

@petrushev
petrushev / nested.data.redis
Created August 9, 2013 09:07
example of storing nested data structures in redis
roomrate
========
{
'city': 'Berlin',
'hotel': 'Hilton',
'date': '2013-08-09'
'room_type': 'single',
'occupancy': 2,
'avail_count': 13,
'booked_count': 4,
@samwize
samwize / mocha-guide-to-testing.js
Created February 8, 2014 05:53
Explain Mocha's testing framework - describe(), it() and before()/etc hooks
// # Mocha Guide to Testing
// Objective is to explain describe(), it(), and before()/etc hooks
// 1. `describe()` is merely for grouping, which you can nest as deep
// 2. `it()` is a test case
// 3. `before()`, `beforeEach()`, `after()`, `afterEach()` are hooks to run
// before/after first/each it() or describe().
//
// Which means, `before()` is run before first it()/describe()
@Kartones
Kartones / postgres-cheatsheet.md
Last active July 17, 2024 05:41
PostgreSQL command line cheatsheet

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

  • -E: will describe the underlaying queries of the \ commands (cool for learning!)
  • -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)
@nucliweb
nucliweb / Clone-All-Repos-GitHub-Organization.md
Last active September 23, 2021 10:12
Clone all repos from a GitHub organization

Publics repos

With Ruby 1.8 (default version on MacOS) :

sudo gem install json
curl -s https://api.github.com/orgs/[ORGANIZATION]/repos | ruby -rubygems -e 'require “json”; JSON.load(STDIN.read).each {|repo| %x[git clone #{repo["ssh_url"]} ]}'

With Ruby 1.9+, the json library is by default thus you just use :

@domenic
domenic / escape-vm.js
Created August 17, 2015 20:20
Escaping the vm sandbox
"use strict";
const vm = require("vm");
const sandbox = { anObject: {} };
const whatIsThis = vm.runInNewContext(`
const ForeignObject = anObject.constructor;
const ForeignFunction = ForeignObject.constructor;
const process = ForeignFunction("return process")();
const require = process.mainModule.require;
require("fs");
@alexvandesande
alexvandesande / Random generator
Last active December 23, 2022 09:10
A very simple random generator. A miner can influence the number by not publishing a block with an unwanted outcome, and forfeiting the 5 block reward.
contract random {
/* Generates a random number from 0 to 100 based on the last block hash */
function randomGen(uint seed) constant returns (uint randomNumber) {
return(uint(sha3(block.blockhash(block.number-1), seed ))%100);
}
/* generates a number from 0 to 2^n based on the last n blocks */
function multiBlockRandomGen(uint seed, uint size) constant returns (uint randomNumber) {
uint n = 0;
for (uint i = 0; i < size; i++){
@axic
axic / ecverify.sol
Last active May 13, 2024 12:07
Ethereum ECVerify
//
// The new assembly support in Solidity makes writing helpers easy.
// Many have complained how complex it is to use `ecrecover`, especially in conjunction
// with the `eth_sign` RPC call. Here is a helper, which makes that a matter of a single call.
//
// Sample input parameters:
// (with v=0)
// "0x47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad",
// "0xaca7da997ad177f040240cdccf6905b71ab16b74434388c3a72f34fd25d6439346b2bac274ff29b48b3ea6e2d04c1336eaceafda3c53ab483fc3ff12fac3ebf200",
// "0x0e5cb767cce09a7f3ca594df118aa519be5e2b5a"