節點JS沒有返回結果

Question

這是我的代碼。當我發送請求時，我沒有收到結果。我不明白爲什麼它不是在情況1工作。我修改它一點點，並把它放在然後，它正在工作。

我在做什麼錯在這裏？ 爲什麼它不適用於案例1？ 如何使它的情況下，使用1 res.end（）之類的情況下3.

案例1工作，指出：

var vigeonCollector = function(req, res) { 

// console.log(req.body); 
try { 
    var store = JSON.parse(JSON.stringify(req.body).toString('utf8').replace("'",'"')); 
} 
catch (e) { 
    console.log("Error in JSON Parsing!"); 
    return res.status(422).json({"status":false, "message":"Unparsble JSON"}); 
} 

var payloads = []; 

store.timestamp = getTimeStamp(); // Should be tagged with current timestamp. 

// Adding event_day IST and UTC format. 
var currentUTCTime = new Date(); 
var currentISTTime = new Date(currentUTCTime.toLocaleString('en-US', { timeZone: 'Asia/Kolkata' })); 
store.event_day = currentUTCTime.toLocaleString().split(',')[0]; 
store.event_day_ist = currentISTTime.toLocaleString().split(',')[0]; 
store.advertiser_id_met = store.advertiser_id; 
store.device_id_met = store.device_id; 


// Call get on redis only once and use it for attribution. 
var redis_result; 
redis.get(store.device_id).then(function(jresult){ 
    redis_result = JSON.parse(jresult); 
    console.log(redis_result); 
    if (store.event_type == "UNINSTALLS") { 

     // Attributing user installed UTM Params. 
     store.event_properties.utm_medium = redis_result.user_installed_medium; 
     store.event_properties.utm_source = redis_result.user_installed_source; 
     store.event_properties.utm_campaign = redis_result.user_installed_campaign; 
     store.advertiser_id = redis_result.advertiser_id; 

    } 
    else { 

     // Tagging last user session UTM Params. 
     store.event_properties.utm_medium = redis_result.medium; 
     store.event_properties.utm_source = redis_result.source; 
     store.event_properties.utm_campaign = redis_result.campaign; 

    } 

    temp_obj = { topic: "vnk-clst", messages: JSON.stringify(store)}; 
    payloads.push(temp_obj); 
    console.log(payloads); 
    console.log("I'm Done!"); 

}); 

producer.send(payloads, function(err, data){ 
    console.log(data); 
    if (err) return res.status(503).json({ "status": false, "message": "503 Service Unavailable", "error": err }); 
    else return res.status(200).json({ "status": true, "message": "OK"}); 
}); 

}

案例2：

var vigeonCollector = function(req, res) { 

// console.log(req.body); 
try { 
    var store = JSON.parse(JSON.stringify(req.body).toString('utf8').replace("'",'"')); 
} 
catch (e) { 
    console.log("Error in JSON Parsing!"); 
    return res.status(422).json({"status":false, "message":"Unparsble JSON"}); 
} 

var payloads = []; 

store.timestamp = getTimeStamp(); // Should be tagged with current timestamp. 

// Adding event_day IST and UTC format. 
var currentUTCTime = new Date(); 
var currentISTTime = new Date(currentUTCTime.toLocaleString('en-US', { timeZone: 'Asia/Kolkata' })); 
store.event_day = currentUTCTime.toLocaleString().split(',')[0]; 
store.event_day_ist = currentISTTime.toLocaleString().split(',')[0]; 
store.advertiser_id_met = store.advertiser_id; 
store.device_id_met = store.device_id; 


// Call get on redis only once and use it for attribution. 
var redis_result; 
redis.get(store.device_id).then(function(jresult){ 
    redis_result = JSON.parse(jresult); 
    console.log(redis_result); 
    if (store.event_type == "UNINSTALLS") { 

     // Attributing user installed UTM Params. 
     store.event_properties.utm_medium = redis_result.user_installed_medium; 
     store.event_properties.utm_source = redis_result.user_installed_source; 
     store.event_properties.utm_campaign = redis_result.user_installed_campaign; 
     store.advertiser_id = redis_result.advertiser_id; 

    } 
    else { 

     // Tagging last user session UTM Params. 
     store.event_properties.utm_medium = redis_result.medium; 
     store.event_properties.utm_source = redis_result.source; 
     store.event_properties.utm_campaign = redis_result.campaign; 

    } 

    temp_obj = { topic: "vnk-clst", messages: JSON.stringify(store)}; 
    payloads.push(temp_obj); 
    console.log(payloads); 
    console.log("I'm Done!"); 

producer.send(payloads, function(err, data){ 
    console.log(data); 
    if (err) return res.status(503).json({ "status": false, "message": "503 Service Unavailable", "error": err }); 
    else return res.status(200).json({ "status": true, "message": "OK"}); 
}); 

}); 

} 

案例3：添加res.end（）只是b在最後}。

Answer 1

在案例1中調用then直接不會等到您提供給它的函數中的所有代碼都已完成。因此，在填充有效載荷之前，呼叫producer.send(...)太早。正確的方法是將producer.send(...)包含到您給then()的功能中。撥打res.end()不應該在這裏相關。