Pg-graph

This library allows you to directly generate json responses in Postgres. Including nested one-to-many and one-to-one relations through a easy to use api.

When do you need this?

You are using Postgres as your relational database
You are using a serverless stack
You want to generate GraphQL like responses from your api (nested multiple levels), but you are lacking the SQL skills to create the required complicated queries
You want a library that is lightweight and fast

Why not PostgREST / Hasura / Graphile?

You need an additional server and you don't have control over the queries that can be done against your database

Why not Prisma?

Prisma is very heavy and IMO unsuitable for serverless.
It generates inefficient queries (subqueries everywhere)

Why is pg-graph a good solution?

It does not try to hide the SQL. You use it in combination with pg. The following code generates a query to get relations 3 levels deep:

const query = graphQuery()

query.source('user', user => {
    user.field('name')
    user.many('blog', 'posted_by', blog => {
        blog.field('name')

        blog.many('comment', comment => {
            comment.field('message')
        })
    })
})

Get the SQL code through the toSql method:

const sql = query.toSql()

Run it with pg

const row = await client.query(sql).then(result => result.rows[0])

console.log(row.data)

Note that your data is ready to be returned from you api. No need to loop through all rows and convert it to json.

Ideas