Learn Flow, Neo4j and Ruby

In this course we will learn some of the basics of getting data into and out of Neo4J, as well as touch on some of the libraries and tooling available in the Neo4J community ecosystem, which we will leverage to quickly create and use a full-featured GraphQL API.

We will start by learning how to run and interact with Neo4J locally. Then we will develop a graph model in which to store the data that we pull from SWAPI via REST. We will then create an Apollo GraphQL API driven by a few simple schemas which fit into this model. We will then write some simple code to crawl SWAPI and insert the data into Neo4J through our GraphQL API. Once there is data in the store, we will learn about some of the features in `neo4j-graphql-js` that make connecting and accessing our graph Nodes easier.

Neo4j delivers the lightning-fast read and write performance you need. Neo4j combines native graph storage, scalable architecture optimized for speed, and ACID compliance to ensure predictability of relationship-based queries.

neo4j

Build a Neo4J & GraphQL API

Rails is a web-application framework that includes everything needed to create database-backed web applications according to the Model-View-Controller (MVC) pattern.

rails

Expanding on [Part 1](https://egghead.io/lessons/angularjs-rails-todo-api-part-1), this lesson will look at how to bootstrap AngularJS in a rails application as part of the asset pipeline. With Angular available, you'll see how to communicate with the Rails API using $resource.

Rails Todo API Part 2

flow

We'll go over some of the built-in types in Flow and how to add them to our projects by adding type annotations to our variables in JavaScript. We'll also learn about type mismatch errors when we give a variable a value that doesn't match its type annotation and how to fix it.

Primitive Types in Flow

AngularJS is an open-source JavaScript framework, maintained by Google, that assists with running single-page applications. Its goal is to augment web-based applications with model–view–controller (MVC) capability, in an effort to make both development and testing easier.

angularjs

Rails makes an excellent choice for delivering data to AngularJS via REST apis. In this first lesson of a two part series, you'll see how to create a simple API for CRUD operations on TODOs using Rails. This isn't an introduction to Rails, and assumes you know the basics. 

Rails Todo API Part 1

Let's learn how to set up Facebook's Flow inside of a project and write a simple typecheck task that will let us run Flow against any files in our codebase.

Up and Running with Facebook Flow for Typed JavaScript

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

Nuclide is the IDE Facebook employees use to write React code. But setting it up to use Flow type checking and Eslint to lint files on the fly is tricky. This video shows you how. 

Setup Nuclide to use Flow and Eslint (Mac)

Create a search directive with AngularJS and Rails. You'll want to take a look at the related [Rails TODO API Part 1](https://egghead.io/lessons/angularjs-rails-todo-api-part-1) and [Rails TODO API Part 2](https://egghead.io/lessons/angularjs-rails-todo-api-part-2). This is **not** a Rails how-to, so some knowledge there is expected to get up and running.

Search Directive with Rails

In this lesson we are going to add types throughout our basic todo list component. This includes type checking the component props, local state, and property methods. 

Type Check React Components With Flow

In this lesson we are going to take a React and Redux application and add flow types throughout. This includes type checking a react component, a reducer, some actions, and a connect method. 

Type Check Redux Apps with Flow

Jekyll is a parsing engine bundled as a ruby gem used to build static websites from dynamic components such as templates, partials, liquid code, markdown, etc. Jekyll is known as "a simple, blog aware, static site generator".

jekyll

[Jekyll](https://jekyllrb.com/) is a static site generator built in [Ruby](https://www.ruby-lang.org/en/) and available to generate and host websites on [GitHub Pages](https://pages.github.com/). In this course, you'll install the Jekyll gem, use the command line tool to generate a new project, inspect the scaffolded project, and finally, serve the starter website.

Install Jekyll and generate initial, scaffolded website

There are different types of data in Neo4J: Nodes and Relationships. We will cover the ways to create each type of data: creating nodes with properties, creating nodes with relationships, and creating constraints on nodes and relationships.

Create Nodes and Relationships in Neo4J with Cypher

Once there is data in Neo4J, we need to be able to access it. We will cover the structure of a cypher query to return parts of our graph.

Read Nodes and Relationships in Neo4J with Cypher

The data in our graph is unlikely to stay the same forever. We will cover the syntax used to find and modify existing data in different ways through the use of parameters.

Update Nodes and Relationships in Neo4J with Cypher

Nothing lives forever, so we need to know how to use DELETE and DETACH to get rid of nodes and relationships we no longer want in our graph.

Delete Nodes and Relationships in Neo4J with Cypher

We will learn about `neo4j-graphql-js` and how to leverage it to quickly create a full-featured API backed by Neo4J. We will create a few simple schemas to represent our model.

Use neo4j-graphql-js to Create a Simple API

We will learn to use the `@relation` directive provided by `neo4j-graphql-js` to make the relationships in our model explicit in our schemas.

Explicitly Model Schema Relationships with the @relation Directive in neo4j-graphql-js

We will use automatically generated mutations in a Apollo GraphQL API augmented with `neo4j-graphql-js` to insert data that we get from SWAPI into Neo4J.

Create Data in Neo4J Through a GraphQL API

We will use the `@cypher` directive provided by `neo4j-graphql-js` to return data about how nodes are related to each other in our schemas without writing custom resolvers.


Build Complex Schema Relationships with the @cypher Directive in neo4j-graphql-js

We will use our own custom mutations in an Apollo GraphQL API to update or create data that we scrape from SWAPI into Neo4J with. We will use the `@cypher` directive to use custom merge statements in these mutations.


Create Custom GraphQL Mutations with the @cypher Directive in neo4j-graphql-js

If you make a mistake when naming your database column, and have data that you want to keep unchanged. You can use the change method with the rename_column definition in your migrations files to update a single column name in your database.