Learn Mongoose, Screen-reader and Tmux

A large number of people are unable to use the web effectively due to an impairment or disability.

As developers there are several tools and techniques we can use to make our web applications accessible, ensuring a great user experience that includes everyone.

We all agree that Accessibility is important. However, it’s a broad landscape and can be overwhelming figuring out where to start!

Erin Doyle is an expert in creating accessible React applications and has developed a course that will give you a concrete process for testing, refactoring, and building your applications with accessibility in mind.

After this course, you'll have a jump start on auditing and fixing accessibility issues in your applications and gain a better understanding of your target users and how to approach your web app design from their perspectives.


React is one of the web’s most popular frameworks for building JavaScript applications. 

If you know what you’re doing, React can drastically simplify how you build, use, and maintain code.

Whether you’re a React newbie or you’re ready for advanced techniques, you can level-up with egghead. Explore our in-depth courses, lessons, and community resources to build more powerful applications and crack open your career.

react

Develop Accessible Web Apps with React

Learn to manage your terminal sessions and work more effectively from the command line using tmux. If you use the command line at all, tmux can make your life easier.

tmux bills itself as a terminal multiplexer. It allows you to wrangle multiple terminal sessions from one window. Instead of keeping track of many terminal windows yourself, you can use tmux to create, organize, and navigate between them. Even more importantly, tmux lets you detach from and re-attach sessions, so that you can leave your terminal sessions running in the background and resume them later. This is especially useful if you're working on a remote server: you can set up a persistent session that will continue running when you close your laptop. You can even share a tmux session to facilitate pair programming.

It lets you switch easily between several programs in one terminal, detach them (they keep running in the background) and reattach them to a different terminal.

tmux

Wrangle your terminal with tmux

Express is a minimal and flexible Node.js web application framework that provides a robust set of features for web and mobile applications.

express

Mongoose allows you to easily select resources by ID from your MongoDB. This is an important aspect to creating an API.

Select by ID with Mongoose and Express

In this lesson, we'll learn how to detach from a running tmux session and leave it running in the background. Then, we can re-attach to it later.

We'll cover:
- How to exit a session by killing all active panes
- Detaching explicitly with C-b d
- Detaching a specific session with C-b D
- Viewing all running tmux sessions using tmux ls
- Reattaching with tmux attach -t

Reuse terminal workspaces using tmux sessions

In tmux, a window is a collection of panes. Creating multiple windows is a great way to organize your workspace. In this lesson, we'll cover:

- How to create a new window within a tmux session, using `C-b c`
- Navigating between windows with `C-b n` and `C-b p`

Create collections of panes using tmux windows

screen-reader

There are many techniques for hiding content in user interfaces, and not all are created equal! Learn how different hiding techniques in HTML, CSS and ARIA impact keyboard and screen reader users in addition to visual display. As a bonus, we'll also take a look using a screen reader on a mobile device.

How Visible vs. Hidden Elements Affect Keyboard/Screen Reader Users

In this lesson, we'll look at how to manage your history between tmux sessions, and ensure that your setup preserves your bash history between multiple windows. By adding a special PROMPT_COMMAND to your .bashrc, you can update and reload your history after every command, regardless of if you're in a different session, window, or tab.


Handle history in tmux sessions

Sometimes you'll want to zoom in on a specific pane within a tmux window. We'll learn to use C-b z to temporarily zoom in on one pane, as well as how to resize your panes with C-b -L, -R, -U, and -D.


Zoom and resize to view a particular pane within tmux

Learn to organize your workspace using tmux. We'll create a new tmux session and learn how to create and navigate panes within a tmux window.

We'll cover:

- How to create new panes via vertical splits with C-b %
- How to create new panes via horizontal splits with C-b "
- Navigating between panes with C-b and arrow keys
- Closing panes with exit or Ctrl-d
- Viewing available commands with C-b ?

Organize your terminal using tmux panes

It's a lot easier to manage your tmux session when they have sensible names. We'll cover:

- How to create a new, named tmux session with tmux new -s
- Rename an existing tmux session using tmux rename-session -t
- Renaming sessions with C-b $
- Listing sessions with C-b s

Manage terminal workspaces using session naming

One non-obvious, but extremely useful, feature in tmux is copy-pasting text between panes. This also allows you to scroll back in a tmux sessoin. We'll cover how to use copy and paste in tmux using C-b [ and C-b ], for both emacs- and vim-style keybindings.

Copy and paste text from a tmux session

You can modify tmux's behavior with your tmux configuration file, .tmux.conf. You can use your tmux config to change color schemes, set custom keybindings, set defaults, modify the status bar, and more. In this lesson, we'll change some of the default color options as well as modify the prefix key.


Customize tmux with tmux.conf

By using ssh, you can share a tmux session, making pair programming much easier. We'll learn how to share a tmux session with another user. 


Share a tmux session for pair programming with ssh

We'll learn how to use mouse mode in tmux, including enable mouse control for resizing, scrolling and selecting panes. We'll also set keybindings in our tmux configuration to control mouse mode. 

Enable mouse mode in tmux

Do you have a standard workflow that involves setting up a specific tmux layout, or running certain commands? By writing tmux scripts, you can automate your tedious daily setup, while simultaneously documenting it for yourself. We'll cover the tmux command equivalents of common key bindings and write some simple, useful scripts.


Automate your workflow using tmux scripts

The Chrome Developer Tools (DevTools for short), are a set of web authoring and debugging tools built into Google Chrome.

chrome-devtools

What's in a name? In this lesson, I'll explain the concept of naming interactive elements for screen reader users, including forms, buttons, and links. You'll learn how to debug accessible names and descriptions using the Chrome Accessibility Developer Tools (previously a Canary experiment, now in Chrome), using multiple labeling techniques. We'll also listen to the effects of proper accessible names and descriptions in Voiceover and Safari.

For more information and the nitty-gritty browser implementation algorithm, refer to WAI-ARIA 1.1: 
- https://www.w3.org/TR/wai-aria-1.1/#namecalculation
- https://www.w3.org/TR/accname-1.1/

What is Accessible Name Calculation?

Learn how to access the VoiceOver training and utility preferences on MacOs and how to make customizations to the screen reader.

Access and Customize VoiceOver Settings on MacOS

Learn the basics of navigating through a web page using VoiceOver on MacOS in Safari.

Navigate a Webpage with VoiceOver in Safari

Landmark regions are used by screen readers to make it easier for users to navigate the content on the page by defining the structure of the page.  Tools like the Rotor in VoiceOver rely on landmark regions to provide users with the ability to skip directly to the desired section of the page.  We can do this either using HTML5 landmark elements or `<div>` elements with aria roles. In the past, the recommendation was to use both but now we should only use one or the other.

The following are ARIA roles for landmark regions:
* `banner`
* `complementary`
* `contentinfo`
* `form`
* `main`
* `navigation`
* `search`
* `application`

## References
* https://dequeuniversity.com/assets/html/jquery-summit/html5/slides/landmarks.html
* https://www.w3.org/WAI/GL/wiki/Using_ARIA_landmarks_to_identify_regions_of_a_page
* https://www.w3.org/TR/html-aria/#docconformance

Define Landmark Regions of a web page using ARIA roles

Using our accessibility auditing toolkit we can find issues concerning landmark regions in our web application.  The react-axe library will report findings in the JavaScript console of the browser.  We could also run the axe browser extension to see the same results.  The tota11y browser extension will annotate any landmark regions on the page and therefore if none are annotated it may indicate that they aren't any (_NOTE: tota11y will only annotate landmark regions using aria roles and not those using HTML5 elements_).  Finally using the VoiceOver Rotor in Safari will show us whatever landmark regions have been defined in the Landmarks menu. 

Test for Landmark Region Accessibility Issues in React

Landmark regions are used by screen readers to make it easier for users to navigate the content on the page by defining the structure of the page. Tools like the Rotor in VoiceOver rely on landmark regions to provide users with the ability to skip directly to the desired section of the page. We can do this either using HTML5 landmark elements or <div> elements with aria roles. In the past, the recommendation was to use both but now we should only use one or the other.  We should prefer HTML5 to ARIA roles when possible.

The following are HTML5 elements for landmark regions:
* article
* aside
* header
* footer
* main
* nav
* section

## References
* https://dequeuniversity.com/assets/html/jquery-summit/html5/slides/landmarks.html
* https://www.a11ymatters.com/article/intro-html5-sectioning-elements/
* https://www.w3.org/TR/html-aria/#docconformance