https://github.com/avishwakarma/dgraph-koa

A Graphql Application using Dgraph and Koa
https://github.com/avishwakarma/dgraph-koa

dgraph dgraph-graphql-koa

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A Graphql Application using Dgraph and Koa

• Host: GitHub
• URL: https://github.com/avishwakarma/dgraph-koa
• Owner: avishwakarma
• License: other
• Created: 2019-02-05T20:22:18.000Z (almost 6 years ago)
• Default Branch: master
• Last Pushed: 2019-02-05T21:18:34.000Z (almost 6 years ago)
• Last Synced: 2024-11-15T21:43:54.051Z (2 months ago)
• Topics: dgraph, dgraph-graphql-koa
• Language: JavaScript
• Size: 22.5 KB
• Stars: 2
• Watchers: 1
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# DgraphKoa

Build a GraphQL application using Dgraph and Koa

## Introduction

Dgraph is a distributed, highly available graph database that uses a language

similar to GraphQL to query and mutate data. Unlike GraphQL, Dgraph only defines

schema for predicates (properties) within the graph; there is no concept of

complex types or groups of properties. Because of this it is straight forward to

store any GraphQL schema in Dgraph provided a few restrictions are met.

Given a GraphQL schema, DgraphKoa can do four things:

1. Generate a GraphQL-JS schema that maps GraphQL queries to Dgraph queries

2. Transform Dgraph responses into GraphQL responses (including support for the

   relay connection specification)

3. Generate defaults for create/update/delete/query operations (with filtering,

   ordering and nested create/update mutations)

4. Configure Dgraph's schema with types and indexes each property.

## Getting Started

The [example](https://github.com/ashokvishwakarma/dgraph-koa/tree/master/example) describes

basic usage. First, install dependencies:

```sh

npm install

```

## Using DgraphKoa

Install DgraphQL from npm

```sh

npm install dgraph-koa

```

The entry point to the library is `Server`

```javascript

import { Server } from 'dgraph-koa'

const schema = `

type Person {

  id: ID!

  name: String @filter(types: [EQUALITY])

  children: [Person!]! @reverse(name: "parents")

  parents: [Person!]! @reverse(name: "children")

}`

(async () => {

  const server = new Server({

    debug: true,

    relay: false,

    graphiql: true, // enable Graphiql UI

    graphiqlUrl: '/graphql', // URL for graphql middleware

    dgraph: {

      uri: 'localhost:9080' // Dgraph database uri

    }

  });

  server.updateSchema(schema);

  server.listen(4000, '0.0.0.0', () => {

    console.log("Server started at http://0.0.0.0:4000")

  });

})();

```

### config

DgraphKoa config passed in `Server constructor`

```

debug: boolean // default true

relay: boolean // default false

graphiql: boolean // default true

graphiqlUrl: string // degault /graphql

dgraph: {

  url: string // default localhost:9080,

  credentials: grpc // default grpc.credentials.createInsecure()

}

```

### Adding other routes

The DgraphKoa allow you to add more middlewares and routing rules into the Koa application

```javascript

const server = new Server(...config);

// server.app actual Koa app

server.app.use(

  // middleware

);

server.use(

  // routing rules

);

server.listen(

  // port

  // host

  // callback

)

```

### Special Thanks

[David Peek](https://github.com/dpeek) for his [dgaphql](https://github.com/dpeek/dgraphql) github repo.