Javascript 从使用fetch的函数返回承诺

Javascript 从使用fetch的函数返回承诺,javascript,ecmascript-6,nativescript,es6-promise,fetch-api,Javascript,Ecmascript 6,Nativescript,Es6 Promise,Fetch Api,我的问题是我每隔x秒调用一次刷新令牌函数,我在刷新令牌函数中硬编码了到主页的导航 执行导航时,无法清除函数中的间隔,因为间隔在另一个文件中声明 我想要的是从其他文件调用refreshToken并返回承诺 是否需要将用户导航到主页(如果响应访问令牌或刷新令牌为空,则导航到主页),如果是,则清除间隔并在此之后导航 下面是methods.js中的refreshToken函数: let refreshToken=(url,refresh_token)=>{ console.log("access

我的问题是我每隔x秒调用一次刷新令牌函数,我在刷新令牌函数中硬编码了到主页的导航 执行导航时,无法清除函数中的间隔,因为间隔在另一个文件中声明

我想要的是从其他文件调用refreshToken并返回承诺 是否需要将用户导航到主页(如果响应访问令牌或刷新令牌为空,则导航到主页),如果是,则清除间隔并在此之后导航

下面是methods.js中的refreshToken函数:

let refreshToken=(url,refresh_token)=>{

console.log("access_token check");
let currentMin=getMinute();

if(currentMin===0){
    currentMin=60;
}
if(appSettings.getNumber("tkTime") > currentMin){
    currentMin=currentMin+60;
}

if(currentMin - appSettings.getNumber("tkTime") >= 4){

    fetch(url,{
        headers: new Headers({
            'Content-Type': 'application/json',
            'Authorization':`Bearer ${refresh_token}`
          }),
        method:'POST'
    }).then((res) => {


        return res.json();          
    }).then((data)=>{
        if(data.refresh_token !== null || data.access_token !== null){

            appSettings.setString("refresh_token",data.refresh_token);
            appSettings.setString("access_token",data.access_token);
            appSettings.setNumber("tkTime",getMinute());  
            console.log("token refreshed");
        }
        else{
            topmost().navigate({moduleName:"Home/home",clearHistory: true});
        }

    })
    .catch(error => {
        console.log(error);

    });
}    

}
下面是我从userPage.js调用此函数时的代码部分:

 const myModules = require('~/methods.js');
 myModules.refreshToken(myModules.refUrl,appSettings.getString("access_token"),appSettings.getString("refresh_token"));

ref=timer.setInterval(() => {
    myModules.refreshToken(myModules.refUrl,appSettings.getString("access_token"),appSettings.getString("refresh_token"));
},1000*30);

从函数返回fetch并写入handle-else条件,否则它将中断

let refreshToken = (url, refresh_token) => {
    console.log("access_token check");
    let currentMin = getMinute();
    if (currentMin === 0) {
        currentMin = 60;
    }
    if (appSettings.getNumber("tkTime") > currentMin) {
        currentMin = currentMin + 60;
    }
    if (currentMin - appSettings.getNumber("tkTime") >= 4) {
        return fetch(url, {
            headers: new Headers({
                'Content-Type': 'application/json',
                'Authorization': `Bearer ${refresh_token}`
            }),
            method: 'POST'
        }).then((res) => {
            return res.json();
        }).then((data) => {
            if (data.refresh_token !== null || data.access_token !== null) {
                appSettings.setString("refresh_token", data.refresh_token);
                appSettings.setString("access_token", data.access_token);
                appSettings.setNumber("tkTime", getMinute());
                console.log("token refreshed");
            } else {
                topmost().navigate({
                    moduleName: "Home/home",
                    clearHistory: true
                });
            }
        })
    } else {
        // .then will throw an error if not write
        return new Promise(resolve => resolve( /*Some Data*/ ));
    }
}

从函数中返回承诺,然后执行
.then(data=>{if(!data.token){clearInterval();navigate();}}).catch(console.error)
在另一个模块中的部分。@Bergi我的问题是如何从函数中返回承诺在这种情况下,我知道如何使用,然后在承诺链前面放一个
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