How do you mutate state in plugins?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Vue.js conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
Similar to components you can't mutate state directly but they can trigger changes by by committing mutations. This
way a plugin can be used to sync a data source to the store.
For example, createWebSocketPlugin plugin is used to sync a websocket data source to the store.
export default function createWebSocketPlugin (socket) {
return store => {
socket.on('data', data => {
store.commit('receiveData', data)
})
store.subscribe(mutation => {
if (mutation.type === 'UPDATE_DATA') {
socket.emit('update', mutation.payload)
}
})
}
}
And then configure plugin in vuex store as below
const plugin = createWebSocketPlugin(socket)
const store = new Vuex.Store({
state,
mutations,
plugins: [plugin]
})
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