【前端】websocket 讲解与项目中的使用

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import { EventLsbridge } from ‘@/common/eventLsbridge’
import { loadFromSession } from ‘@/common/session-storage’
import { Message } from ‘element-ui’
const timer = {
reconnectObj: null,
wsTimeoutObj: null,
serverTimeoutObj: null,
// 重连时间间隔(s)
reconnectTime: 3
}
const state = {
ws: null,
// 心跳时间（s）
wsTimeout: 20,
// 等待心跳响应时间(s)，等待心跳的响应时间要大于心跳时间4s以上
waitHeartTime: 24
}
const mutations = {
set_reconnectObj: (state, val) => {
state.reconnectObj = val
},
}
const actions = {
// 心跳重置
wsHearReset({ dispatch }) {
clearTimeout(timer.serverTimeoutObj)
clearTimeout(timer.wsTimeoutObj)
dispatch(‘wsHeartStart’)
},
// 开启心跳
wsHeartStart({ state, dispatch }) {
timer.wsTimeoutObj = setTimeout(() => {
if(state.ws && state.ws.readyState == 1) {
state.ws.send(‘’)
} else {
dispatch(‘handlerWSError’)
}
}, state.wsTimeout * 1000)
timer.serverTimeoutObj = setTimeout(() => {
console.log(‘接收心跳异常！’)
dispatch(‘handlerWSError’)
}, state.waitHeartTime * 1000)
},
// 初始化ws连接
initWebsocket({ dispatch, state }) {
if (state.ws) {
return
} else {
return new Promise(resolve => {
let url = ${process.env['VUE_APP_WEBSOCKET']}/websocket
state.ws = new WebSocket(url)
state.ws.addEventListener(‘open’, e => {
console.log(‘长连接连接成功’)
clearTimeout(timer.reconnectObj)
dispatch(‘wsHeartStart’)
})
state.ws.addEventListener(‘message’, e => {
dispatch(‘wsHearReset’)
dispatch(‘handlerWSMessage’, e)
})
state.ws.addEventListener(‘close’, e => {
console.log(‘ws close’)
dispatch(‘handlerWSClose’, e)
})
state.ws.addEventListener(‘error’, e => {
console.log(‘ws error’)
dispatch(‘handlerWSError’, e)
})
})
}
},
handlerSend({state}, id = -1) {
if(!state.ws) {
return
}
if(state.ws.readyState == 1) {
state.ws.send(
JSON.stringify({
id
})
)
}
},
handlerWSClose({ state }, e) {
state.ws?.close()
},
handlerWSError({state, dispatch}, e) {
console.log(‘ws-error’)
state.ws?.close()
state.ws = null
dispatch(‘reconnect’)
},
reconnect({state, commit, dispatch}) {
console.log(‘ws-重连’)
clearTimeout(timer.wsTimeoutObj)
clearTimeout(timer.serverTimeoutObj)
clearTimeout(timer.reconnectObj)
if (loadFromSession(‘userInfo’)?.userId) {
Message.warning(‘网络出现异常，请检查网络后尝试刷新页面’)
}
timer.reconnectObj = window.setTimeout(() => {
dispatch(‘initWebsocket’)
timer.reconnectTime += 4
if(timer.reconnectTime > 60) {
timer.reconnectTime = 20
}
}, timer.reconnectTime * 1000)
},
// ws回调
handlerWSMessage({state}, e) {
let respData = {}
try {
respData = JSON.parse(e.data)
} catch (e) {
// not todo
}
if (respData?.data) {
EventLsbridge.vueEmit(EventLsbridge.eventName.wsData, respData)
}
}
}
export default {
namespaced: true,
state,
mutations,
actions
}