Elaine Terkwood

#Inject javascript into HTML pages from console

An easy way to inject Javascripts into the current loaded dom using the developer console in chrome.

jQuery

var script = document.createElement('script');
script.src = 'http://code.jquery.com/jquery-1.7.2.min.js';

Description

[Server] GStreamer ---> HTML [Client]

Require

gstreamer-1.x
Browser which supports video tag of HTML5

debian

This post is deprecated!

Its contents have been moved to the NixOS wiki here, where they are being kept up to date. Please follow the instructions there instead!

The original post is below for posterity.

Most GStreamer examples found online are either for Linux or for gstreamer 0.10.

This particular release note seems to have covered important changes, such as:

ffmpegcolorspace => videoconvert
ffmpeg => libav

Applying -v will print out useful information. And most importantly the negotiation results.

Semantic versioning regex

^([0-9]+)\.([0-9]+)\.([0-9]+)(?:-([0-9A-Za-z-]+(?:\.[0-9A-Za-z-]+)*))?(?:\+[0-9A-Za-z-]+)?$

example

http://regexr.com/3er1i

also see

Semantic versioning http://semver.org/
Source of the regex npm/node-semver#32

EBS and EFS Volumes with Docker For AWS using REX-Ray

This procedure will deploy Docker For AWS and go through the steps to build REX-Ray containers. This process will have some hiccups because Docker for AWS will provision resources in different availability zones (AZs). Multiple workers/agents will be spread across AZs (not regions) which means a potential host failure will trigger Swarm to restart containers that could spread across an AZ. If a container is restarted in a different AZ, the pre-emption mechanism for REX-Ray will not work because it no longer has access to the volume in the former AZ.

Deploy Docker for AWS.

Launch Stack

SSH into one of your Docker Manager Nodes

	iex(2)> pid = spawn Traps, :init, []
	waiting to die...
	#PID<0.92.0>
	Nobody tried to kill me! ^_^
	waiting to die...
	Nobody tried to kill me! ^_^
	waiting to die...
	iex(3)> Process.exit pid, :normal
	true
	(⊙＿⊙') somebody tried to kill me! {:EXIT, #PID<0.88.0>, :normal}

	FROM ubuntu:16.04

	RUN apt update
	RUN apt install build-essential curl -y
	RUN apt install file -y
	RUN apt install asciinema -y
	RUN apt install unzip -y
	RUN apt install emacs24-nox -y
	RUN apt install vim -y
	RUN apt install nano -y

	# ATTENTION: This is now supported in plug_cowboy as of 2.1.0:
	# https://hexdocs.pm/plug_cowboy/Plug.Cowboy.Drainer.html

	defmodule DrainStop do
	@moduledoc """
	DrainStop Attempts to gracefully shutdown an endpoint when a normal shutdown
	occurs. It first shuts down the acceptor, ensuring that no new requests can be
	made. It then waits for all pending requests to complete. If the timeout
	expires before this happens, it stops waiting, allowing the supervision tree
	to continue its shutdown order.

	$ sudo vim /etc/systemd/system/docker-compose.service


	[Unit]
	Description=DockerCompose
	After=docker.service
	Requires=docker.service

	[Service]
	ExecStart=/opt/bin/docker-compose -f /home/core/docker-compose.yml up -d