Tutorial by Examples

List of commands that will be introduced here: ls #view contents of a directory touch #create new file mkdir #create new directory cp #copy contents of one file to another mv #move file from one location to another rm #delete a file or directory ls examples jennifer@my_co...

michael@who-cares:~$ The symbol ~ after the who-cares: is the current directory. ~ actually means the person's home directory. In this case, that's /home/michael. michael@who-cares:~$ cd Downloads michael@who-cares:~/Downloads$ Looks for Downloads in the current directory, then makes that th...

Elixir is available in main packages repository. Update the packages list before installing any package: emerge --sync This is one step installation: emerge --ask dev-lang/elixir

Install jekyll on Linux Mint 18 with the following steps: sudo apt install ruby sudo apt install build-essential sudo apt install ruby-dev sudo gem install jekyll

Open a command prompt with Administrator access Install Chocolatey: @powershell -NoProfile -ExecutionPolicy Bypass -Command "iex ((new-object net.webclient).DownloadString('https://chocolatey.org/install.ps1'))" && SET PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin Close the comm...

Authentication filters Are a new kind of filter added in ASP.NET MVC 5.0 .That run prior to authorization filters in the ASP.NET MVC pipeline and allow you to specify authentication logic per-action, per-controller, or globally for all controllers. Authentication filters process credentials in th...

Encryption is used to transform data in its orignal format (Eg: The contents of a letter, Credentials part of authorizing a financial transaction) to something that cannot be easily reconstructed by anyone who is not intended to be part of the conversation. Basically encryption is used to preve...

Ionic Platform: Build, push, deploy, and scale your Ionic apps, the easy way. Title Description: The Ionic Platform is a cloud platform for managing and scaling cross-platform mobile apps. Integrated services enable you and your team to build, deploy, and grow your apps efficiently. Docume...

When a hit is sent to Google Analytics the data must be processed. Processing latency is 24-48 hours. This means that it can take time before you will see data under standard reports (Not real-time) any data that you do see may not be correct as it has probably not completed processing. Standard a...

A with_items loop in ansible can be used to easily loop over values. - name: Add lines to this file lineinfile: dest=/etc/file line={{ item }} state=present with_items: - Line 1 - Line 2 - Line 3

You can also loop over a variable list. From vars: favorite_snacks: - hotdog - ice cream - chips and then the loop: - name: create directories for storing my snacks file: path=/etc/snacks/{{ item }} state=directory with_items: '{{ favorite_snacks }}' If you are using Ansible ...

It is possible to create more complex loops with dictionaries. From vars: packages: - present: tree - present: nmap - absent: apache2 then the loop: - name: manage packages package: name={{ item.value }} state={{ item.key }} with_items: '{{ packages }}' Or, if you don't like ...

You can use a dictionary for a slightly more complex loop. - name: manage packages package: name={{ item.name }} state={{ item.state }} with_items: - { name: tree, state: present } - { name: nmap, state: present } - { name: apache2, state: absent }

You can create nested loops using with_nested. from vars: keys: - key1 - key2 - key3 - key4 then the loop: - name: Distribute SSH keys among multiple users lineinfile: dest=/home/{{ item[0] }}/.ssh/authorized_keys line={{ item[1] }} state=present with_nested: - [ 'calvin...

To decouple and reuse the same error logging code for all your services you need two boilerplate classes and tuck them away in a library somewhere. ErrorhandlerAttribute implementing IServiceBehavior. FaultErrorhandler implementing IErrorhandler which logs all the exceptions. [AttributeUsage(Attr...

Modals slide in off screen to display a temporary UI, often used for login or signup pages, message composition, and option selection. import { ModalController } from 'ionic-angular'; import { ModalPage } from './modal-page'; export class MyPage { constructor(public modalCtrl: ModalControlle...

Instead of bloating your main js file that contains your navigator with buttons. It's cleaner to just inject buttons on-demand in any page that you need. //In the page "Home", I want to have the right nav button to show //a settings modal that resides in "Home" component. c...

'use strict'; import React, {Component} from 'react'; import ReactNative from 'react-native'; const { AppRegistry, StyleSheet, Text, View, Navigator, Alert, TouchableHighlight } = ReactNative; //This is the app container that contains the navigator stuff class AppC...

HttpClient httpClient = new StdHttpClient.Builder(). url("http://yourcouchdbhost:5984"). username("admin"). password("password"). build(); CouchDbInstance dbInstance = new StdCouchDbInstance(httpClient);

Given you have a valid CouchDbInstance instance, you connect to a database within CouchDB in the following manner CouchDbConnector connector = dbInstance.createConnector("databaseName", true);