karelsteinmetz/bobflux

Bobflux is pure functional implementation of FLUX architecture

Bobflux

• is pure functional implementation of FLUX architecture
• is inspired by Flux, Reflux and Redux
• fits and depends on Bobril

Installation

npm i bobflux --save

How to run example through bobril-build

npm install bobril-build -g

bb

Fun-model

• is core of bobflux,
• is independent on bobril, can be used for React applications,
• there is fun-model you can see some notes about flux, immutability etc.

Common keywords in Bobflux application

• one store for one application state
• application state:
• is global state
• is composition of sub states
• actions are create by action factory with specified cursor and handler. Handler creates new instance of state or it can return the same state
• Bobril is here for "rendering" (View)
• Bobril component context (b.IBobrilCtx) should be used for intermediate state (drag & drop, input border color on focus etc.)

Lifecycle

Getting started video [cz]

State

• is object
• is global state of application
• one instance is held in store
• default state must be set before firts usage

//state.ts
import * as f from 'bobflux';

export interface ITodo {
    id: number;
    isDone: boolean;
    name: string;
}

export interface ITodosState extends f.IState {
    editedTodo: ITodo;
    todos: ITodo[];
}

//app.ts - main application file in bobril-build or systemjs
import * as f from 'bobflux';
import * as s from './states';

f.bootstrap(s.default());

Views/Pages

• can be pure bobril components or can be created by bobflux

Bobflux Components

• is derived component from Bobril
• gets state through cursor which has been specified in creation
• sets last state into component context
• offers state property in context (ctx.state)
• component should not have data
• all data should be passed by state
• why?
• implements shouldChange and holds last state from last rendering
• protects against useless rendering parts in your application
• there are two kinds of components:
• component
  • is common component which has state in context
• routeComponent
  • is fitted for bobril router and has state in context
  • is virtual component which wrappes bobflux component
  • bobflux component cannot be used in router beacause you can not specify cursor in route handler. Creation is invoked by router.
• if you operate with b.invalidate(ctx) in your component you can force shouldChange by ctx.forceShouldChange

import * as b from 'bobril';
import * as gui from 'bobril-css-bootstrap';
import * as f from 'bobflux';
import * as s from './states';
import * as a from './actions';
import * as c from './cursors';

export let create = f.createRouteComponent<s.ITodosState, any>({
    render(ctx: f.IContext<s.ITodosState>, me: b.IBobrilNode, oldMe?: b.IBobrilCacheNode) {
        me.children = [
            addForm(c.editedTodo),
            table(c.todos)
        ]
    }
})

let addForm = f.createComponent<s.ITodo, any>({
    render(ctx: f.IContext<s.ITodo>, me: b.IBobrilNode, oldMe?: b.IBobrilCacheNode) {
        me.children = gui.form({
            isInlined: true,
            content: [
                gui.inputFormField('', ctx.state.name, a.updateNewTodoName),
                gui.button({ label: 'Add', onClick: () => { a.addTodo(); return true; } })
            ]
        })
    }
})

Cursor

• has key which specifies path to target propery of objects or subobjects in global application state
• there are two kinds of cursors:
• for maps - "all objects/classes" in js

export let editedTodoName: f.ICursor<string> = {
    key: 'todoSection.editedTodo.name'
}

export let todos: f.ICursor<s.ITodo[]> = {
    key: 'todoSection.todos'
}

• for array items with static cursor key

export let firstTodo: f.ICursor<s.ITodo> = {
    key: 'todoSection.todos.0'
}

export let firstTodoName: f.ICursor<string> = {
    key: 'todoSection.todos.0.name'
}

• for array items with dynamic cursor key

export let todosIndexFactory: f.ICursorFactory<s.ITodo, number> = {
    create: (index) => {
        return { key: `todoSection.todos.${index}` };
    }    
}

export let todoNameThroghtIndexFactory: f.ICursorFactory<string, number> = {
    create: (index) => {
        return { key: `todoSection.todos.${index}.name` };
    }    
}

Action

• returns new instances of modified state and its sub states
• beware on array operations like push etc.
• use as much as possible specific cursors
• if you want to modify more sub states then you should create two actions with specified cursors. Then invoke actions synchronously. b.invalidate waits for both actions. If actions take a long time then intermediate state will be rendered between actions.
• function should not be passed through parameters into action

Common creation and invoking

• implementation:

export let removeTodo = f.createAction<s.ITodo[], number>(c.todos, (todos, id) => {
    return [...todos.filter(t => t.id !== id)];
});

• invoking:

actions.removeTodo(t.id);

Without parameters

• implementation:

export let removeTodoId1 = bobflux.createAction(cursors.todos, (todos: states.ITodo[]): states.ITodo[] => {
    return [...todos.filter(t => t.id !== 1)];
});

• invoking:

actions.removeStaticTodo();

If you need pass more parameters into action

• implementation:

export interface IChangeDoneStatusParams {
    id: number;
    isDone: boolean;
}

export let changeDoneStatus = f.createAction<s.ITodo[], IChangeDoneStatusParams>(c.todos, (todos, params) => {
    return todos.map(t => {
        if (t.id === params.id)
            return f.shallowCopy(t, (nT) => {
                nT.isDone = params.isDone;
                return nT;
            });
        return t;
    })
});

• invoking:

 actions.changeDoneStatus({ id: t.id, isDone: value })

With cursor factory

• implementation:

let testAction = af.createAction<tds.ITodo, tds.ITodoParams>(
    {
        create: (params) => {
            return { key: `todos.${params.index}` };
        }
    },
    (state, params) => { return params.todo }
);

• invoking:

testAction({ index: 1, todo: { done: false, name: 'New second todo' } });

Issues

• beware on invoking because params of actions are optional!!! Compiler cannot check this mistake.