Typesafe actions reducer builder

This library provides the function createReducerBuilder: it's a 100% type-hinted builder which creates a redux reducer for a particular state allowing the developer to define reducers per-action basis. It uses the typesafe-actions library to interact with the actions.

Features

• Builder for redux reducers
• 100% type-hinted (no way to go "off the trails")
• returns an Immutable<TState> using immer, always providing immutable states to redux

Usage

1// myReducer.ts
2
3import createReducerBuilder from 'typesafe-actions-reducer-builder'
4
5// Those are all typesafe-actions actions
6import {
7  metaAuthorChangeAction,      // PayloadAction<string, string>
8  metaTitleChangeAction,       // PayloadAction<string, string>
9  metaDescriptionChangeAction, // PayloadAction<string, string>
10  metaTagsAddAction,           // PayloadAction<string, string>
11  metaTagsRemoveAction,        // PayloadAction<string, string>
12  bodyChangeAction,            // PayloadAction<string, string>
13} from './actions.ts'
14
15interface DocumentState {
16  meta: {
17    author: string
18    title: string
19    description: string
20    tags: string[]
21  }
22  body: string
23}
24
25const initialState: DocumentState {
26  meta: {
27    author: '',
28    title: '',
29    description: '',
30    tags: [],
31  },
32  body: ''
33}
34
35
36const reducer = createReducerBuilder(initialState)
37  // reducer's type: Reducer<DocumentState, PayloadAction<string, string>>
38  .handle(metaAuthorChangeAction).reducer((state = initialState, action) => {
39    state.meta.author = action.payload
40    return state
41  })
42  .handle(metaTitleChangeAction).reducer((state = initialState, action) => {
43    state.meta.title = action.payload
44    return state
45  })
46  .handle(metaDescriptionChangeAction).reducer((state = initialState, action) => {
47    state.meta.description = action.payload
48    return state
49  })
50  .handle(metaTagsAddAction).reducer((state = initialState, action) => {
51    if (!state.meta.tags.includes(action.payload)) {
52      state.meta.tags.push(action.payload)
53    }
54    return state
55  })
56  .handle(metaTagsRemoveAction).reducer((state = initialState, action) => {
57    if (!state.meta.tags.includes(action.payload)) {
58      return
59    }
60    state.meta.tags.splice(state.meta.tags.indexOf(action.payload), 1)
61    return state
62  })
63  .handle(bodyChangeAction).reducer((state = initialState, action) => {
64    state.body = action.payload
65    return state
66  })
67  .build()
68
69export default reducer
70