Eric gzeureka

Configure Git to use a proxy

In Brief

You may need to configure a proxy server if you're having trouble cloning or fetching from a remote repository or getting an error like unable to access '...' Couldn't resolve host '...'.

Consider something like:

What do Etcd, Consul, and Zookeeper do?
- Service Registration:
  - Host, port number, and sometimes authentication credentials, protocols, versions numbers, and/or environment details.
- Service Discovery:
  - Ability for client application to query the central registry to learn of service location.
- Consistent and durable general-purpose K/V store across distributed system.
  - Some solutions support this better than others.
  - Based on Paxos or some derivative (i.e. Raft) algorithm to quickly converge to a consistent state.
Centralized locking can be based on this K/V store.

Comparison of Spring Cloud with Eureka

I feel Consul.io does better in the following area:

The focus on scriptable configuration allows for better container management.
Eureka requires either external Configuration Server or multiple configuration files.
The options for securing communications is more advanced.
Eureka requires creating application with security settings desired. Default will allow HTTP only. Registration of end points assumes http but can be forced to https with code.

How to change your commit messages in Git?

At some point you’ll find yourself in a situation where you need edit a commit message. That commit might already be pushed or not, be the most recent or burried below 10 other commits, but fear not, git has your back 🙂.

Not pushed + most recent commit:

git commit --amend

This will open your $EDITOR and let you change the message. Continue with your usual git push origin master.

1. Clone your fork:

git clone [email protected]:YOUR-USERNAME/YOUR-FORKED-REPO.git

2. Add remote from original repository in your forked repository:

cd into/cloned/fork-repo
git remote add upstream git://github.com/ORIGINAL-DEV-USERNAME/REPO-YOU-FORKED-FROM.git
git fetch upstream

create a blank c9 workspace (Ubuntu)
create bin directory mkdir ~/bin && cd ~/bin
download the lein file wget https://raw.githubusercontent.com/technomancy/leiningen/stable/bin/lein
set it to be executable chmod 755 lein
tell the JVM where to find your home directory (just type this into the console like the rest) export LEIN_JVM_OPTS="-Duser.home=$HOME"
run lein for self-install

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

	"""Calculate the probability of generating a duplicate random number after
	generating "n" random numbers in the range "d".

	Usage: python birthday_probability.py n [d=365]

	Each value can either be an integer directly, or in the format "2**x", where
	x is the number of bits in the value.

	For example, to calculate the probability that two people will have the same
	birthday in a room with 23 people:

	App configuration in environment variables: for and against

	For (some of these as per the 12 factor principles)

	1) they are are easy to change between deploys without changing any code

	2) unlike config files, there is little chance of them being checked
	into the code repo accidentally

	3) unlike custom config files, or other config mechanisms such as Java

	# 你可以从该 URL 下载这个配置文件: http://surge.run/config-example/ios.conf
	# 用编辑器编辑后，再通过 iTunes, URL, AirDrop 或者 iCloud Drive 复制回 iOS 设备
	# Version 2.0

	[General]
	# 日志等级: warning, notify, info, verbose (默认值: notify)
	loglevel = notify
	# 跳过某个域名或者 IP 段，这些目标主机将不会由 Surge Proxy 处理。(在 macOS
	# 版本中，如果启用了 Set as System Proxy, 那么这些值会被写入到系统网络代理
	# 设置中.)