Actix Web - Async JSON Service Boilerplate

Motivation

Learning Rust can be difficult. Providing an idiomatic example of a purely JSON based, asynchronous service. Hope it helps more projects get started.

Current Stack

• Actix
• Serde / Mock JSON FS
• JSON Function helpers for returning Actix::HttpResponse
• Environment variables in .json file
• Threaded DB connection pool for handling multiple async requests at once
• future_ok! macro for writing handlers
• sql_struct! macro to create structs that satisfy diesel's ORM and raw sql queries

Goals

• Leverage actix-web to fullest
• Leverage serde for JSON
• Async for all routes using Futures
• Best libraries, practices and performance

Opinions

• JSON services need sensisble defaults out of the box
• Experimental/Mock routes favor generic Map<String, Value> over serialize/deserialize and strict types
• Metaprogramming (macros) used to reduce repeated and often lengthy definitions / signatures

Environment Variables

Create a file in the root (not in src)

// env.json
{
  "postgres":{
    "username": "xxxxx",
    "password": "xxxxx"
  }
}

Mocks Status

• GET /mock_get/{filename} will return the data from the file if it exists and 404 if it doesn't
• POST /mock_set/{filename} will create/overwrite a file and set contents to body of request

TODO

1. Middleware for JWT?

DB Setup (Postgres)

Database examples expect the following:

• There is a table schema called test
• There is a table called item
• item has field id that is type serial
• item has field data that is type text

Notes on setting up PostgresSQL

Start service

# sudo service postgresql start

Enter console without switching

# sudo -u postgres psql

Switch to postgres user

# sudo i -u postgres

Create new user

sudo -u postgres createuser --interactive (default connect to db by username so maybe use actix?)

Create database

# create database actix;

Connect to database

\c actix

Create schema test and table w/ serial id

# create schema test;

# create table test.item(id serial, data text);

Grant permissions to schema / database

# GRANT USAGE ON SCHEMA database_name TO username;
# GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA database_name TO username;
# GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA schema_name TO username;
# GRANT ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA schema_name TO username;
# GRANT ALL PRIVILEGES ON DATABASE database_name TO username;