const localstorageMiddleware = (function(){ /** * The actual middleware inteceptor **/ return store => next => action => { console.log(action) // proceed as normal first // this way, any reducers and middleware do their thing BEFORE we store our new state next(action); switch( action.type ){ case 'MOPIDY_SET_CONFIG': var mopidy = { host: action.config.host, port: action.config.port }; localStorage.setItem('mopidy', JSON.stringify(mopidy)); break; case 'SPOTIFY_SET_CONFIG': var spotify = { country: action.config.country, locale: action.config.locale }; localStorage.setItem('spotify', JSON.stringify(spotify)); break; case 'SPOTIFY_AUTHORIZATION_GRANTED': var spotify = JSON.parse( localStorage.getItem('spotify') ); if( !spotify ) spotify = {}; Object.assign( spotify,{ authorized: true, access_token: action.data.access_token, refresh_token: action.data.refresh_token, token_expiry: action.data.token_expiry } ); localStorage.setItem('spotify', JSON.stringify(spotify)); break; case 'SPOTIFY_TOKEN_REFRESHED': var spotify = JSON.parse( localStorage.getItem('spotify') ); if( !spotify ) spotify = {}; Object.assign( spotify,{ access_token: action.data.access_token, token_expiry: action.data.token_expiry } ); localStorage.setItem('spotify', JSON.stringify(spotify)); break; } } })(); export default localstorageMiddleware