Learn Jq, Nvda and Sequelize

jq is a lightweight and flexible command-line JSON processor.

jq can help you quickly filter massive amounts of JSON data, but how can you turn it into a CSV, so you can process it quickly with a database or spreadsheet application?

This lesson shows how to select the data you want for your CSV with jq, and uses the helper utility linked below to output as CSV.

https://github.com/joelpurra/jq-hopkok/tree/master/src/tabular

Convert JSON to CSV with jq

NVDA (NonVisual Desktop Access) is a free “screen reader” which enables blind and vision impaired people to use computers.

nvda

NVDA is a popular open source screen reader on Windows that works well with Firefox. It's similar to JAWS, another popular Windows screen reader that works best with IE. But NVDA has no licensing fee plus an open bug tracker, making it great for users as well as developer testing. 

In this lesson, you'll learn how to browse a webpage using NVDA's keyboard shortcuts, including headings navigation, skip links, and the Elements List. You'll also learn a bit about Forms Mode and how it impacts screen reader navigation.  For more tips, check out the resources below.

## Resources
- [Using NVDA to Emulate Web Accessibility](http://webaim.org/articles/nvda/)
- [NVDA Keyboard Shortcuts](https://dequeuniversity.com/screenreaders/nvda-keyboard-shortcuts)
- [Understanding Screen Reader Interaction Modes](http://tink.uk/understanding-screen-reader-interaction-modes/)
- [Three Things You Should Know Before Using Voiceover for Testing](http://webaim.org/blog/three-things-voiceover/)

## Installing NVDA
If you're on a Windows machine, you can install [NVDA directly](http://www.nvaccess.org/download/). If you're on a Mac or Linux, you could install a Windows virtual machine:

- [Install VirtualBox](https://www.virtualbox.org/wiki/Downloads)
- [Get a Windows VM from Microsoft](https://developer.microsoft.com/en-us/microsoft-edge/tools/vms/) - I use IE11
- [Install Firefox](https://www.mozilla.org/en-US/firefox/new/) - install on the VM!
- [Install NVDA](http://www.nvaccess.org/download/)
- [How to Map Your Mac's Capslock Key to a NVDA or JAWS Key in a Windows VM](https://www.marcozehe.de/2015/06/07/how-to-map-your-macs-capslock-key-to-a-nvda-or-jaws-key-in-a-windows-virtual-machine/)

Testing for Accessibility with the NVDA Screen Reader on Windows

Sequelize is a promise-based ORM for Node.js and io.js. It supports the dialects PostgreSQL, MySQL, MariaDB, SQLite and MSSQL and features solid transaction support, relations, read replication and more.

sequelize

Sequelize attribute getters and setters are a convenient way to encapsulate extra logic for model properties. In this video, we'll cover adding getters and setters to enhance and even virtualize a column.

Sequelize: Getters, Setters and Virtual Columns

jq is a lightweight and flexible command-line JSON processor. It is extremely useful for processing data from APIs to better understand the data your code will be consuming, before you write the code. In this lesson I introduce you to jq and show you the basic features it provides using the Star Wars API (http://swapi.co) as our data source. Topics covered include filtering, piping, object construction and data manipulation.

Using jq to parse the Star Wars API

Models in the Node.js ORM, Sequelize, can be expanded with both class level and instance level functions. This video will show you how to extend your models to add helpers or business logic, and explain the methods execution scope.

Sequelize: Class & Instance Methods

Javascript and database systems tend to be at odds with regard to how tables and columns should be named. Sequlize provides all the tools necessary to satisfy naming conventions in both your Node.js code and in your SQL database.

Sequelize: Model & Column Casing

Bash, unfortunately, doesn’t ship with a command that can work with JSON natively. In this lesson, we’ll learn how to read and do basic queries on JSON with `jq`, an installable command line tool that makes working with JSON in bash really easy. We'll pipe the JSON output of the Github API to jq to extract values. 

Note: jq has to be installed. On macOS, the easiest way to do this is to run `brew install jq`.  To view install instructions for all platforms, see https://stedolan.github.io/jq/download/. 

Read and Use JSON in Bash with jq

In this lesson, we'll apply our `jq` skills and write a script that gets a list of dependencies from package.json and greps for usages of every package. If a package is unused, it's marked for removal. 

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