rust-graphql-juniper-actix-diesel-postgres

by lucperkins

An example GraphQL server written in Rust

154 Stars 10 Forks Last release: Not found 32 Commits 0 Releases

Available items

No Items, yet!

The developer of this repository has not created any items for sale yet. Need a bug fixed? Help with integration? A different license? Create a request here:

Rust + GraphQL + Juniper + Diesel + Postgres + Actix

Yes, I know that this is a borderline absurd web stack for the ubiquitous TODO application but I had a lot of trouble getting this all to work. I started using these things for a more ambitious project and I'd love to spare you the trouble. So here's some basic boilerplate to get you up and running.

Components

Here's what does what:

Component

Tool/lib
Web server actix-web
Database PostgreSQL
SQL engine Diesel
GraphQL library Juniper
GraphQL UI GraphQL Playground

Run locally

Before you get started, make sure that you have PostgreSQL, Rust, Cargo, and the Diesel CLI installed and that you have Postgres running somewhere.

# Fetch the repo
git clone https://github.com/lucperkins/rust-actix-diesel-postgres-juniper
cd rust-actix-diesel-postgres-juniper

Set up the database

cp .env.example .env # Modify this file to match your Postgres installation

diesel setup diesel migration run

cargo run # could take a while!

The

DATABASE_URL
can be any Postgres installation. For my purposes, I have it set to
postgres://localhost:5432/todos
.

Once the server is running, you can access the GraphQL Playground UI at http://localhost:4000/graphql.

Schema

The server implements the following GraphQL schema:

type Todo {
  id: ID!
  task: String!
  done: Boolean!
}

input CreateTodoInput { task: String! done: Boolean }

type Query { allTodos: [Todo!]! getTodoById(id: Int): Todo }

type Mutation { createTodo(input: CreateTodoInput): Todo markTodoAsDone(id: Int): Todo markTodoAsNotDone(id: Int): Todo }

schema { Query Mutation }

Tour of the codebase

File

What it provides
context.rs
The GraphQL context that handles query execution
data.rs
A

Todos
struct and some helper functions encapsulate the Diesel-powered Postgres querying logic
db.rs
The connection pool that handles the Postgres connection
endpoints.rs
The
/graphql
HTTP endpoint that makes GraphQL and the GraphQL Playground work
graphql.rs
The
Query
,
Mutation
, and
Schema
objects that undergird the GraphQL interface
lib.rs
Just the standard
lib.rs
main.rs
Actix HTTP server setup
models.rs
All of the data types used for querying Postgres and providing GraphQL results
schema.rs
The Diesel-generated table schema

Future TODOs

Get it? Anyway, here's some areas for improvement (pull requests very much welcome):

  • Error handling — Right now errors basically propagate directly from Diesel/Postgres into the GraphQL JSON output, which is subpar. If any of you can point me to good educational resources on this, please file an issue!
  • Better execution engine — The server uses the extremely powerful actix-web but the actual DB interactions don't use Actix actors and it'd take this setup to the next level if they did.
  • Use macros for schema generation — The powerful
    juniper_from_schema
    macro could help reduce boilerplate and improve development velocity.

Acknowledgments

I'm basically a beginner with Rust and would not have been able to put this together without peeking long and hard at the example projects and blog posts listed below. The lower-level bits you see here are basically stolen from BrendanBall. All that I've added is the

Todos
data construct for executing queries.

Example projects

Blog posts

We use cookies. If you continue to browse the site, you agree to the use of cookies. For more information on our use of cookies please see our Privacy Policy.