fetch-try-catch-pattern.md

prepare

• rewrite fetch to catch httpcode

const httpCodeFetch = async ({ url, config = initialConfig }) => {
    const res = await fetch(url, config)
    if (res.status === 204) return {}
    if (res.ok) {
        return res.json()
    } else {
        const obj = await res.json()
        // new Error(res.statusText)
        throw { status: res.status, ...obj }
    }
}

1. common code

 
 httpCodeFetch(url,...).then(res => {
    do(res)
 }).catch(err =>{
    if(err.status === 401) do401(err)
    error(err)
 })

2.try catch

 
 try{
     const res = httpCodeFetch()
     do(res)
 }catch(err){
    if(err.status === 401) do401(err)
     error(err)
 }