hurricane-voronin

Naming Classes Without a 'Manager'

• SomethingManager
• Design Patterns
  • Creational
    • Factory Method
    • Abstract Factory
    • Builder
• Prototype

bastman

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

kgriffs

# Configuration file for runtime kernel parameters.
# See sysctl.conf(5) for more information.

# See also http://www.nateware.com/linux-network-tuning-for-2013.html for
# an explanation about some of these parameters, and instructions for
# a few other tweaks outside this file.
#
# See also: https://gist.github.com/kgriffs/4027835
#
# Assumes a beefy machine with lots of network bandwidth

xl7dev

> cd /Applications/VMware Fusion.app/Contents/Library/VMware OVF Tool
> ./ovftool --acceptAllEulas /Users/marco/Documents/Virtual\ Machines.localized/Windows\ 8.1\ x64.vmwarevm/Windows\ 8.1\ x64.vmx /Users/marco/Desktop/Win81.ova

P7h

tmux vs. screen commands

---

Action	tmux	screen
start a new session	tmux tmux new tmux new-session	screen
start a new session with a name	tmux new -s name	screen -S name
re-attach a detached session	tmux attach tmux attach-session	screen -r
re-attach a detached session with a name	tmux attach -t name tmux a -t name	screen -r name
re-attach an attached session (detaching it from elsewhere)	tmux attach -dtmux attach-session -d	screen -dr

ixdy

Setting up ssh public key authentication on macOS using a YubiKey 4

I largely followed Florin's blog post, but have a few notes to add regarding issues I encountered:

Basic setup notes

1. I used a YubiKey 4, while the blog describes using a YubiKey NEO. I'm sure a YubiKey 5 would also work. I'm also running macOS 10.13.6.
2. I installed GPGTools as recommended. However, as I'll note later, it seems that gpg-agent only automatically starts when gpg is used; for ssh, you'll need to ensure it's running.
3. Before generating your keys, decide what key size you want to use. If you run the list command inside gpg --edit-card, look for the Key attributes line to see what is currently selected. On my YubiKey 4, it defaulted to 2048 bits for all keys:

Key attributes ...: rsa2048 rsa2048 rsa2048

ursuad

Kafka Topics

List existing topics

bin/kafka-topics.sh --zookeeper localhost:2181 --list

Describe a topic

bin/kafka-topics.sh --zookeeper localhost:2181 --describe --topic mytopic

Purge a topic

bin/kafka-topics.sh --zookeeper localhost:2181 --alter --topic mytopic --config retention.ms=1000

... wait a minute ...

rothgar

# Idempotent way to build a /etc/hosts file with Ansible using your Ansible hosts inventory for a source.
# Will include all hosts the playbook is run on.
# Inspired from http://xmeblog.blogspot.com/2013/06/ansible-dynamicaly-update-etchosts.html

- name: "Build hosts file"
  lineinfile: dest=/etc/hosts regexp='.*{{ item }}$' line="{{ hostvars[item].ansible_default_ipv4.address }} {{item}}" state=present
  when: hostvars[item].ansible_default_ipv4.address is defined
  with_items: groups['all']

katylava

Update 2022: git checkout -p <other-branch> is basically a shortcut for all this.

FYI This was written in 2010, though I guess people still find it useful at least as of 2021. I haven't had to do it ever again, so if it goes out of date I probably won't know.

Example: You have a branch refactor that is quite different from master. You can't merge all of the commits, or even every hunk in any single commit or master will break, but you have made a lot of improvements there that you would like to bring over to master.

Note: This will not preserve the original change authors. Only use if necessary, or if you don't mind losing that information, or if you are only merging your own work.

hrchu

@startuml
skinparam handwritten true
"You/Browser" -> slack.com: 1. I would like to access my files on Google Drive via your interface.
slack.com -> "You/Browser": 2. You should apply the "Authorization Code" from Google for me first.
"You/Browser" -> account.google.com: 3. I would like to permit slack.com to access my files.
account.google.com -> "You/Browser": 4. Are you sure?
"You/Browser" -> account.google.com: 5. [Y]
account.google.com -> "You/Browser": 6. Okay. Here is the "Authorization Code." Plz give it back to slack.com now.
"You/Browser" -> slack.com: 7. You can do what I asked now (with the Authorization Code which is just received from Google.) 
slack.com -> account.google.com: 8. I would like to exchange the "Authorization Code" for the "Access Token."