Monthly Archives: October 2016

npm package.json

  • ~version “Approximately equivalent to version” See npm semver – Tilde Ranges & semver (7)
  • ^version “Compatible with version” See npm semver – Caret Ranges & semver (7)
  • version Must match version exactly
  • >version Must be greater than version
  • >=version etc
  • <version
  • <=version
  • 1.2.x 1.2.0, 1.2.1, etc., but not 1.3.0
  • http://sometarballurl (this may be the URL of a tarball which will be downloaded and installed locally
  • * Matches any version
  • latest Obtains latest release

References
http://stackoverflow.com/questions/22343224/difference-between-tilde-and-caret-in-package-json

PM2 CheatSheet

 

# Fork mode
$ pm2 start app.js --name my-api # Name process

# Cluster mode
$ pm2 start app.js -i 0        # Will start maximum processes with LB depending on available CPUs
$ pm2 start app.js -i max      # Same as above, but deprecated yet.

# Listing

$ pm2 list               # Display all processes status
$ pm2 jlist              # Print process list in raw JSON
$ pm2 prettylist         # Print process list in beautified JSON

$ pm2 describe 0         # Display all informations about a specific process

$ pm2 monit              # Monitor all processes

# Logs

$ pm2 logs [--raw]       # Display all processes logs in streaming
$ pm2 flush              # Empty all log file
$ pm2 reloadLogs         # Reload all logs

# Actions

$ pm2 stop all           # Stop all processes
$ pm2 restart all        # Restart all processes

$ pm2 reload all         # Will 0s downtime reload (for NETWORKED apps)
$ pm2 gracefulReload all # Send exit message then reload (for networked apps)

$ pm2 stop 0             # Stop specific process id
$ pm2 restart 0          # Restart specific process id

$ pm2 delete 0           # Will remove process from pm2 list
$ pm2 delete all         # Will remove all processes from pm2 list

# Misc

$ pm2 reset <process>    # Reset meta data (restarted time...)
$ pm2 updatePM2          # Update in memory pm2
$ pm2 ping               # Ensure pm2 daemon has been launched
$ pm2 sendSignal SIGUSR2 my-app # Send system signal to script
$ pm2 start app.js --no-daemon
$ pm2 start app.js --no-vizion
$ pm2 start app.js --no-autorestart
$ pm2 start app.js           # Start app.js

$ pm2 start app.js -- -a 23  # Pass arguments '-a 23' argument to app.js script

$ pm2 start app.js --name serverone # Start a process and name it as serverone
                                    # you can now stop the process by doing
                                    # pm2 stop serverone

$ pm2 start app.js --node-args="--debug=7001" # --node-args to pass options to node V8

$ pm2 start app.js -i 0             # Start maximum processes depending on available CPUs (cluster mode)

$ pm2 start app.js --log-date-format "YYYY-MM-DD HH:mm Z"    # Log will be prefixed with custom time format

$ pm2 start app.json                # Start processes with options declared in app.json
                                    # Go to chapter Multi process JSON declaration for more

$ pm2 start app.js -e err.log -o out.log  # Start and specify error and out log
$ pm2 start echo.pl --interpreter=perl

$ pm2 start echo.coffee
$ pm2 start echo.php
$ pm2 start echo.py
$ pm2 start echo.sh
$ pm2 start echo.rb
{
  ".sh": "bash",
  ".py": "python",
  ".rb": "ruby",
  ".coffee" : "coffee",
  ".php": "php",
  ".pl" : "perl",
  ".js" : "node"
}

References
http://pm2.keymetrics.io/docs/usage/quick-start/#cheatsheet

CSS3 Animations

An animation lets an element gradually change from one style to another.

/* The animation code */
@keyframes example {
    from {background-color: red;}
    to {background-color: yellow;}
}

/* The element to apply the animation to */
div {
    width: 100px;
    height: 100px;
    background-color: red;
    animation-name: example;
    animation-duration: 4s;
}
/* The animation code */
@keyframes example {
    0%   {background-color: red;}
    25%  {background-color: yellow;}
    50%  {background-color: blue;}
    100% {background-color: green;}
}
/* The animation code */
@keyframes example {
    0%   {background-color: red; left:0px; top:0px;}
    25%  {background-color: yellow; left:200px; top:0px;}
    50%  {background-color: blue; left:200px; top:200px;}
    75%  {background-color: green; left:0px; top:200px;}
    100% {background-color: red; left:0px; top:0px;}
}

Delay an Animation

div {
    width: 100px;
    height: 100px;
    position: relative;
    background-color: red;
    animation-name: example;
    animation-duration: 4s;
    animation-delay: 2s;
}

Set How Many Times an Animation Should Run

div {
    width: 100px;
    height: 100px;
    position: relative;
    background-color: red;
    animation-name: example;
    animation-duration: 4s;
    animation-iteration-count: 3;
}

use the value “infinite” to make the animation continue for ever

Run Animation in Reverse Direction or Alternate Cycles

div {
    width: 100px;
    height: 100px;
    position: relative;
    background-color: red;
    animation-name: example;
    animation-duration: 4s;
    animation-iteration-count: 3;
    animation-direction: reverse;
}
div {
    width: 100px;
    height: 100px;
    position: relative;
    background-color: red;
    animation-name: example;
    animation-duration: 4s;
    animation-iteration-count: 3;
    animation-direction: alternate;
}

Specify the Speed Curve of the Animation

#div1 {animation-timing-function: linear;}
#div2 {animation-timing-function: ease;}
#div3 {animation-timing-function: ease-in;}
#div4 {animation-timing-function: ease-out;}
#div5 {animation-timing-function: ease-in-out;}

References
http://www.w3schools.com/css/css3_animations.asp

CSS3 Transitions

CSS3 transitions allows you to change property values smoothly (from one value to another), over a given duration.

div {
    width: 100px;
    height: 100px;
    background: red;
    -webkit-transition: width 2s; /* For Safari 3.1 to 6.0 */
    transition: width 2s;
}
div:hover {
    width: 300px;
}

Change Several Property Values

div {
    -webkit-transition: width 2s, height 4s; /* Safari */
    transition: width 2s, height 4s;
}

Specify the Speed Curve of the Transition

#div1 {transition-timing-function: linear;}
#div2 {transition-timing-function: ease;}
#div3 {transition-timing-function: ease-in;}
#div4 {transition-timing-function: ease-out;}
#div5 {transition-timing-function: ease-in-out;}

Delay the Transition Effect

div {
    -webkit-transition-delay: 1s; /* Safari */
    transition-delay: 1s;
}

Transition + Transformation

div {
    -webkit-transition: width 2s, height 2s, -webkit-transform 2s; /* Safari */
    transition: width 2s, height 2s, transform 2s;
}

References
http://www.w3schools.com/css/css3_transitions.asp

CSS3 2D Transforms

translate()
The translate() method moves an element from its current position (according to the parameters given for the X-axis and the Y-axis).

div {
    -ms-transform: translate(50px, 100px); /* IE 9 */
    -webkit-transform: translate(50px, 100px); /* Safari */
    transform: translate(50px, 100px);
}

rotate()
The rotate() method rotates an element clockwise or counter-clockwise according to a given degree.

div {
    -ms-transform: rotate(20deg); /* IE 9 */
    -webkit-transform: rotate(20deg); /* Safari */
    transform: rotate(20deg);
}

scale()
The scale() method increases or decreases the size of an element (according to the parameters given for the width and height).

div {
    -ms-transform: scale(2, 3); /* IE 9 */
    -webkit-transform: scale(2, 3); /* Safari */
    transform: scale(2, 3);
}

skewX()
The skewX() method skews an element along the X-axis by the given angle.

div {
    -ms-transform: skewX(20deg); /* IE 9 */
    -webkit-transform: skewX(20deg); /* Safari */
    transform: skewX(20deg);
}

skewY()
skew()
matrix()
The matrix() method combines all the 2D transform methods into one.

References
http://www.w3schools.com/css/css3_2dtransforms.asp

Change DNS on Ubuntu

In /etc/NetworkManager/NetworkManager.conf comment out the line dns=dnsmasq

sudo nano /etc/NetworkManager/NetworkManager.conf
[main]
plugins=ifupdown,keyfile,ofono
#dns=dnsmasq

and restart the NetworkManager service.

sudo restart network-manager

sudo rm -f /etc/resolv.conf # Delete the symbolic link
sudo nano /etc/resolv.conf # Create static file

# Content of static resolv.conf
nameserver 208.67.220.220
nameserver 208.67.220.222

References
http://askubuntu.com/questions/690511/how-to-change-dns-in-ubuntu-15-10