Prototype of a "Low Code Data App".

General Idea

It starts with a generic, secure web gui.

Entities can be defined on-the-fly, as well as their relationship. Web forms and lists are generated to maintain data (documents) of this entities.

All data, users and authorizations are within hierarchical scopes (like tenants). Entity definitions and data can be inherited to lower hierarchy scopes. A web gui user can switch the scope in the gui.

Entities are bundled in apps, so they can be exported and imported via a app marketplace. Apps are installed and can be customized within a scope. Tags can also be used to assign apps to a scope.

To start process adapters can subscribe to events, e.g. data changes. Adapters use service credentials defined on a dedicated scope.

All operations are exposed as API, e.g. for the adapters.

Run it

git clone https://github.com/ma-ha/lowcode-data-app.git
cd lowcode-data-app/app
npm i
node example-standalone | node_modules/bunyan/bin/bunyan 

Open http://localhost:8888/app/index.html

Login with user demo and password demo

Sample code

Standalone mode:

let lowCodeApp = require( 'lowcode-data-app' )

lowCodeApp.init({
  DATA_DIR : '../dta/',
  GUI_URL  : 'http://localhost:8888/app/',
  URL_PATH : '/app',
  OIDC_SERVER : true
})

Entity / Document Model

Data types (and their Web GUI mapping)

• Strings (simple input fields)
• Number (simple input fields)
• Boolean (checkboxes)
• Date (date picker)
• Select with an option array (pull down of values)
• DocMap master-detail reference (link to filtered docs)
• SelectRef to other entity (pull down of ids)
• MultiSelectRef to other entity (pull down of ids)
• UUID auto generated, if field name is id this will be the collection id
• Metrics link to a metrics (time series data) for this entity id
• JSON (Multi Line Edit)
• Link(simple input fields, will take placeholders)
• Event (link to send an event. Ref can have a simple condition to render the link, e.g. "status == ready" or "status != in progress,done")

So relations are

• 1:n = docMap
• n:1= selectRef
• n:m = multiSelectRef

Integration

APIs

Adapters and connectors can use ReST APIs, see API and Format Reference Docu.

Event Hub

Adapters can subscribe to data events, to start processes or sync the data with external systems.

See example code.

GUI Links

Entities can refer to external GUI Apps using links. Placeholders in the links are populated with the entity data.

Customizing

The GUI framework is "easy-web-app" and the underlying api server is "express".

Persistence

The persistence uses simple files and a memory cache. This is not recommended for production use.

I should be simple to replace the persistence with a document DB. Simply rewrite:

• app-dta.js
• app-dta-user.js

OpenID Connect

The implementation brings it's own OICD auth server.

Have a look into the config files to configure a real OICD IAM.

The invitation process may need some additional OICD onboarding flow, if th users aren't already there.

Web Content

Some static doc files, GTC, imprint etc. need to be customized to your needs.

A simple markdown docu can be implemented, as well as a self-service onboarding, see api-content.js.

CSS

Simple color scheme changes can be done easily, just focus on the 1st 15 lines in custom.css