redux-saga-thunk

Dispatching an action handled by redux-saga returns promise. It looks like redux-thunk, but with pure action creators.

class MyComponent extends React.Component {
  componentWillMount() {
    // `doSomething` dispatches an action which is handled by some saga
    this.props.doSomething().then((detail) => {
      console.log('Yaay!', detail)
    }).catch((error) => {
      console.log('Oops!', error)
    })
  }
}

redux-saga-thunk uses Flux Standard Action to determine action's payload, error etc.

Motivation

There are two reasons I created this library: Server Side Rendering and redux-form.

When using redux-saga on server, you will need to know when your actions have been finished so you can send the response to the client. There are several ways to handle that case, and redux-saga-thunk approach is the one I like most. See an example.

With redux-form, you need to return a promise from dispatch inside your submit handler so it will know when the submission is complete. See an example

Finally, that's a nice way to migrate your codebase from redux-thunk to redux-saga, since you will not need to change how you dispatch your actions, they will still return promises.

Install

$ npm install --save redux-saga-thunk

Basic setup

Add middleware to your redux configuration (before redux-saga middleware):

import { createStore, applyMiddleware } from 'redux'
import createSagaMiddleware from 'redux-saga'
import { middleware as thunkMiddleware } from 'redux-saga-thunk'
^

const sagaMiddleware = createSagaMiddleware()
const store = createStore({}, applyMiddleware(thunkMiddleware, sagaMiddleware))
                                              ^

Usage

You just need to set meta.thunk to true on your request actions and put it on your response actions inside the saga:

const action = {
  type: 'RESOURCE_REQUEST',
  payload: { id: 'foo' },
  meta: {
    thunk: true
    ^
  }
}

// send the action
store.dispatch(action).then((detail) => {
  // payload == detail
  console.log('Yaay!', detail)
}).catch((e) => {
  // payload == e
  console.log('Oops!', e)
})

function* saga() {
  while(true) {
    const { payload, meta } = yield take('RESOURCE_REQUEST') 
                     ^
    try {
      const detail = yield call(callApi, payload) // payload == { id: 'foo' }
      yield put({
        type: 'RESOURCE_SUCCESS',
        payload: detail,
        meta
        ^
      })
    } catch (e) {
      yield put({
        type: 'RESOURCE_FAILURE',
        payload: e,
        error: true,
        ^
        meta
        ^
      })
    }
  }
}

redux-saga-thunk will automatically transform your request action and inject a key into it.

You can also use it inside sagas with put.resolve:

function *someSaga() {
  try {
    const detail = yield put.resolve(action)
    console.log('Yaay!', detail)
  } catch (error) {
    console.log('Oops!', error)
  }
}

Usage with selectors

To use pending, rejected, fulfilled and done selectors, you'll need to add the thunkReducer to your store:

import { combineReducers } from 'redux'
import { reducer as thunkReducer } from 'redux-saga-thunk'

const reducer = combineReducers({
  thunk: thunkReducer,
  // your reducers...
})

Now you can use selectors on your containers:

import { pending, rejected, fulfilled, done } from 'redux-saga-thunk'

const mapStateToProps = state => ({
  loading: pending(state, 'RESOURCE_CREATE_REQUEST'),
  error: rejected(state, 'RESOURCE_CREATE_REQUEST'),
  success: fulfilled(state, 'RESOURCE_CREATE_REQUEST'),
  done: done(state, 'RESOURCE_CREATE_REQUEST'),
})

API

Table of Contents

• clean
• pending
• rejected
• fulfilled
• done

clean

Clean state

Parameters

• name string
• id (string | number)

Examples

const mapDispatchToProps = (dispatch, ownProps) => ({
  cleanFetchUserStateForAllIds: () => dispatch(clean('FETCH_USER')),
  cleanFetchUserStateForSpecifiedId: () => dispatch(clean('FETCH_USER', ownProps.id)),
  cleanFetchUsersState: () => dispatch(clean('FETCH_USERS')),
})

pending

Tells if an action is pending

Parameters

• state State
• name (string | Array<(string | [string, (string | number)])>)
• id (string | number)

Examples

const mapStateToProps = state => ({
  fooIsPending: pending(state, 'FOO'),
  barForId42IsPending: pending(state, 'BAR', 42),
  barForAnyIdIsPending: pending(state, 'BAR'),
  fooOrBazIsPending: pending(state, ['FOO', 'BAZ']),
  fooOrBarForId42IsPending: pending(state, ['FOO', ['BAR', 42]]),
  anythingIsPending: pending(state)
})

Returns boolean

rejected

Tells if an action was rejected

Parameters

• state State
• name (string | Array<(string | [string, (string | number)])>)
• id (string | number)

Examples

const mapStateToProps = state => ({
  fooWasRejected: rejected(state, 'FOO'),
  barForId42WasRejected: rejected(state, 'BAR', 42),
  barForAnyIdWasRejected: rejected(state, 'BAR'),
  fooOrBazWasRejected: rejected(state, ['FOO', 'BAZ']),
  fooOrBarForId42WasRejected: rejected(state, ['FOO', ['BAR', 42]]),
  anythingWasRejected: rejected(state)
})

Returns boolean

fulfilled

Tells if an action is fulfilled

Parameters

• state State
• name (string | Array<(string | [string, (string | number)])>)
• id (string | number)

Examples

const mapStateToProps = state => ({
  fooIsFulfilled: fulfilled(state, 'FOO'),
  barForId42IsFulfilled: fulfilled(state, 'BAR', 42),
  barForAnyIdIsFulfilled: fulfilled(state, 'BAR'),
  fooOrBazIsFulfilled: fulfilled(state, ['FOO', 'BAZ']),
  fooOrBarForId42IsFulfilled: fulfilled(state, ['FOO', ['BAR', 42]]),
  anythingIsFulfilled: fulfilled(state)
})

Returns boolean

done

Tells if an action is done

Parameters

• state State
• name (string | Array<(string | [string, (string | number)])>)
• id (string | number)

Examples

const mapStateToProps = state => ({
  fooIsDone: done(state, 'FOO'),
  barForId42IsDone: done(state, 'BAR', 42),
  barForAnyIdIsDone: done(state, 'BAR'),
  fooOrBazIsDone: done(state, ['FOO', 'BAZ']),
  fooOrBarForId42IsDone: done(state, ['FOO', ['BAR', 42]]),
  anythingIsDone: done(state)
})

Returns boolean

License

MIT © Diego Haz