j2s

library2.0.13jsnpmunverified

JSON to SQL: build RESTful API servers on the fly by accepting JSON describing SQL query statements. Version 2.0.13 supports CRUD operations, joins, aggregations, where conditions with operators (gt, lt, in, between, etc.), relation manipulation, and configurable access control. It relies on Bookshelf.js (and Knex.js) for ORM and query building, and is tested with Koa.js. Unlike traditional REST frameworks, j2s shifts query complexity to the client, reducing backend code for data fetching.

database

npm install j2s

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · J2S

j2s

databasejavascriptv2.0.13

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

J2s

✓ import J2s from 'j2s'

✗ const J2s = require('j2s')

Default export (ESM-only in v2)

J2s

✓ const J2s = require('j2s').default

✗ const J2s = require('j2s')

CommonJS require must use .default since v2.0.0

j2s

✓ const j2s = require('j2s')

Old CJS style, still works but deprecated

Minimal setup: create Koa app, configure knex/bookshelf, define a model, instantiate J2s, attach controller router.

import J2s from 'j2s'; import Koa from 'koa'; import Router from '@koa/router'; import knex from 'knex'; import bookshelf from 'bookshelf'; const app = new Koa(); const db = knex({ client: 'postgresql', connection: { host: process.env.DB_HOST || '127.0.0.1', database: process.env.DB_NAME, user: process.env.DB_USER, password: process.env.DB_PASS ?? '' } }); const bs = bookshelf(db); const User = bs.Model.extend({ tableName: 'user', hasTimestamps: true }); const j2s = new J2s({ models: { user: User }, knex: db, bookshelf: bs }); const router = new Router(); router.use('/api', j2s.controller()); app.use(router.routes()); app.listen(3000);

Debug

Known issues

breaking'new J2s()' no longer returns the router instance directly; use 'j2s.controller()' to get the router

fix

Change 'app.use(new J2s({...}))' to 'app.use(new J2s({...}).controller())'

affects: >=2.0.0

deprecatedCommonJS require('j2s') returns the module; you must use .default

fix

Use 'const J2s = require('j2s').default'

affects: >=2.0.0

gotchaBookshelf and knex peer dependencies are required but not installed automatically

fix

Install 'npm install bookshelf knex'

affects: >=2.0.0

gotchaOnly tested with Koa.js; may not work with Express or other frameworks

fix

Use Koa.js or wrap j2s controller for other frameworks

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: J2s is not a constructor

Using CommonJS require without .default

fix

const J2s = require('j2s').default

TypeError: router.use is not a function

Passing j2s() result directly to app.use instead of using .controller()

fix

app.use(new J2s(options).controller())

Error: Cannot find module 'bookshelf'

Missing peer dependency bookshelf

fix

npm install bookshelf

Error: knex is not a function

Missing peer dependency knex

fix

npm install knex

Upgrade

Version history

2.0.13latest on npm

Audit

Dependencies

bookshelfrequiredRequired for data modeling and ORM layer

knexrequiredRequired for query building and database access

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/roackb2/j2s ↗

packagej2s ↗

homepagehttps://github.com/roackb2/j2s#readme ↗