Suhovius suhovius

Материалы по Go (golang)

На русском языке

Мануалы и туториалы

[Введение в программирование на Go][1]
[Маленькая книга о Go][3]
[Эффективный Go][2]
Есть еще [Краткий пересказ Effective Go на русском языке][4], но 2009 года

Multiple MySQL Versions with Homebrew

For homebrew version 0.9.5.

brew -v # => Homebrew 0.9.5

Install the current version of mysql.

# Install current mysql version

brew install mysql

How to scale out a Phoenix application with websocket

Foreword

It's relatively easy to scale out stateless web applications. You often only need a reverse proxy. But for those stateful web applications, especially those applications that embeds websocket services in them, it's always a pain to distribute them in a cluster. The traditional way is introducing some external services like Redis to handle pubsub, however, in such way, you often need to change your code. Can Erlang/Elixir, the "concurrency oriented programming languages", best other languages in this use case? Has Phoenix framework already integrated the solution of horizontally scaling websocket? I'll do an experiment to prove (or disprove) that.

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	# IE is still braindead so still use favicon.ico

	convert -resize x16 -gravity center -crop 16x16+0+0 -flatten -colors 256 input.png output-16x16.ico
	convert -resize x32 -gravity center -crop 32x32+0+0 -flatten -colors 256 input.png output-32x32.ico
	convert output-16x16.ico output-32x32.ico favicon.ico

	# Then, HTML needs to specify size="XxY" as largest size due to browser bugs

	<link rel="shortcut icon" href="/favicon.ico" sizes="32x32">

	# 1. Clear retry set

	Sidekiq::RetrySet.new.clear

	# 2. Clear scheduled jobs

	Sidekiq::ScheduledSet.new.clear

	# 3. Clear 'Processed' and 'Failed' jobs

	After automatically updating Postgres to 10.0 via Homebrew, the pg_ctl start command didn't work.
	The error was "The data directory was initialized by PostgreSQL version 9.6, which is not compatible with this version 10.0."

	Database files have to be updated before starting the server, here are the steps that had to be followed:

	# need to have both 9.6.x and latest 10.0 installed, and keep 10.0 as default
	brew unlink postgresql
	brew install [email protected]
	brew unlink [email protected]
	brew link postgresql

	# Automatically instal the latest nginx
	wget -O - http://nginx.org/keys/nginx_signing.key \| sudo apt-key add -

	#Make a backup copy of your current sources.list file
	sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

	#Now copy the following repositories to the end of ` /etc/apt/sources.list`
	echo "deb http://nginx.org/packages/mainline/ubuntu/ trusty nginx" \| sudo tee -a /etc/apt/sources.list
	echo "deb-src http://nginx.org/packages/mainline/ubuntu/ trusty nginx" \| sudo tee -a /etc/apt/sources.list

	git branch -m old_branch new_branch # Rename branch locally
	git push origin :old_branch # Delete the old branch
	git push --set-upstream origin new_branch # Push the new branch, set local branch to track the new remote

	users = User.arel_table
	query = users.project(users[Arel.star])