Ortum

Ortum is a small framework agnostic, unidirectional state management library.
It's inspired by the work of André Staltz' on Profunctor State Optics

Ortum allows your features to be independent from the global state while having the ability to use the global state.
By using this, your features are decoupled from their environment, thus easy to test.

Getting started

Install into your project:

$ npm install --save ortum

Give it a try at: https://stackblitz.com/edit/ortum-counter?file=src/counter.ts

Usage in Javascript

Create an initial state, and use it to create the Profunctor.
The useProfunctor returns an array with two elements:

• the profunctor: basically a store that holds the state and allows access and update it
  using the functions getState, setState and promap.
• an onStateChange that you can pass a callback of (state) => console.log(state)

const { SimpleStateContainer, useProfunctor } = require('ortum');

const initialState = { 
  counter: 0, 
  authors: {
    1: {
      name: 'Andre Staltz',
      github: 'staltz'
    },
    2: {
      name: 'Albert Groothedde',
      github: 'alber70g',
    }
  }
  
};

// Create the app profunctor
const [appProf, onStateChange] = useProfunctor(
  new SimpleStateContainer(initialState),
);

// Listen to state changes
onStateChange((state) => console.log(state));

// Use the profunctor to get and set the state
console.log(appProf.getState()); 
// `{ counter: 0, authors: { .. }  }` 

// Set state using an Updater: prevState => newState
// After this statement you'll get a console.log with 
// // { counter: 1, authors: { .. }  }
appProf.setState((prevState) => {
  return Object.assign(
    {}, 
    prevState, 
    { counter: prevState.counter + 1 }
  )
});

// To create a substate profunctor
const authorsProf = appProf.promap(
  // map/getter
  (state) => state.authors,
  // unmap/setter
  (authors, prevState) => {
    return Object.assign({}, prevState, { authors: authors })
  }
)

console.log(authorsProf.getState()); 
// { 
//   counter: 1,
//   1: {
//     name: 'Andre Staltz',
//     github: 'staltz'
//   },
//   2: {
//     name: 'Albert Groothedde',
//     github: 'alber70g',
//   }
// }