fastGQL

Realtime GraphQL on PostgreSQL / MySQL

About

This project exposes PostgreSQL / MySQL through GraphQL API, with built-in authorization engine. Inspired by Hasura.

This is alpha-version, with some features still in development:

• basic operations
  • query
  • mutate
    • insert
    • update
  • delete
  • subscription
• JWT authentication
• JWT authorization
  • query
  • mutate
  • delete
  • subscription
• authorization engine configured with groovy DSL
  • role-based column access
  • role-based and content-based row access
• user-defined filtering via GraphQL arguments
  • where
  • order by
  • limit
  • offset

Example

Database

CREATE TABLE addresses(
  id INT PRIMARY KEY,
  street VARCHAR(255)
);

CREATE TABLE customers(
  id INT PRIMARY KEY,
  name VARCHAR(255),
  address INT REFERENCES addresses(id)
);

INSERT INTO addresses VALUES (0, 'Danes Hill');
INSERT INTO addresses VALUES (1, 'Rangewood Road');
INSERT INTO customers VALUES (0, 'Stacey', 0);
INSERT INTO customers VALUES (1, 'John', 0);
INSERT INTO customers VALUES (2, 'Daniele', 1);

Simple query

Permissions	JWT token data
permissions { role ('default') { table ('customers') { ops ([select]) { allow 'id', 'name', 'address' } } table ('addresses') { ops ([select]) { allow 'id', 'street' } } } }	{ "role": "default" }
Query	Response
query { customers { id name address address_ref { id street customers_on_address { id } } } }	{ "data": { "customers": [ { "id": 0, "name": "Stacey", "address": 0, "address_ref": { "id": 0, "street": "Danes Hill", "customers_on_address": [ { "id": 0 }, { "id": 1 } ] } }, { "id": 1, "name": "John", "address": 0, "address_ref": { "id": 0, "street": "Danes Hill", "customers_on_address": [ { "id": 0 }, { "id": 1 } ] } }, { "id": 2, "name": "Daniele", "address": 1, "address_ref": { "id": 1, "street": "Rangewood Road", "customers_on_address": [ { "id": 2 } ] } } ] } }

Query with arguments

Permissions	JWT token data
permissions { role ('default') { table ('customers') { ops ([select]) { allow 'id', 'name', 'address' } } table ('addresses') { ops ([select]) { allow 'id', 'street' } } } }	{ "role": "default" }
Query	Response
query { customers ( where:{ name:{_in:["John", "Daniele"]}, _or:[ {id:{_eq:3}}, {address:{_lt:10}} ] }, order_by:{address_ref:{street:desc}} ) { id name address address_ref { id street customers_on_address (limit:1) { id } } } }	{ "data": { "customers": [ { "id": 2, "name": "Daniele", "address": 1, "address_ref": { "id": 1, "street": "Rangewood Road", "customers_on_address": [ { "id": 2 } ] } }, { "id": 1, "name": "John", "address": 0, "address_ref": { "id": 0, "street": "Danes Hill", "customers_on_address": [ { "id": 0 } ] } } ] } }

Query with row access restrictions

{ it.id } in this example is a closure which accepts JWT token data, it is equivalent to Java lambda:

@FunctionalInterface
interface ValueGetter {
  Object getValue(Map<String, Object> jwtData);
}

class C {
  ValueGetter valueGetter = it -> it.get("id");
}

Permissions	JWT token data
permissions { role ('default') { table ('customers') { ops ([select]) { allow 'id', 'name', 'address' check 'id' eq { it.id } } } table ('addresses') { ops ([select]) { allow 'id', 'street' } } } }	{ "role": "default", "id": 0 }
Query	Response
query { customers { id name address_ref { customers_on_address { id } } } }	{ "data": { "customers": [ { "id": 0, "name": "Stacey", "address_ref": { "customers_on_address": [ { "id": 0 } ] } } ] } }

Mutation with preset and validity check

Permissions	JWT token data
permissions { role ('default') { table ('customers') { ops ([select]) { allow 'id', 'name', 'address' check 'id' eq { it.id } } ops ([insert]) { allow 'name', 'address' preset 'id' to { it.id } check 'address' lt 100 } } } }	{ "role": "default", "id": 3 }
Mutation	Response
mutation { insert_customers ( objects:{ name:"Oscar", address:0 } ) { affected_rows } }	{ "data": { "insert_customers": { "affected_rows": 1 } } }
Query	Response
query { customers { id name address } }	{ "data": { "customers": [ { "id": 3, "name": "Oscar", "address": 0 } ] } }

Building and running

Development

Start Postgres container:

scripts/start_postgres.sh

Start FastGQL in dev mode with hot reload:

./gradlew vertxRun

Go to localhost:8080/graphiql/ or query localhost:8080/graphql

Production

Build production bundle:

./gradlew installDist

Execute production version:

build/install/fastgql/bin/fastgql run --conf src/main/resources/conf-postgres.json dev.fastgql.FastGQL