我试图在 for 循环中调用多个外部 api，但根据结果，我只从 for 循环中获得一次迭代，将响应发送回。
是的，这不是处理多 api 请求的正确方法，请建议最好的方法，因为它必须是顺序 req/res
第一个请求 - 调用以查找相应的 api。Response 保存要输入到两个在 for 循环中调用的 api 的数据。
For-loop Second API Request - 将数据提供给第三个 API 请求。
var express = require('express');
var bodyParser = require('body-parser');
var Request = require("request");
var app = express();
app.use(bodyParser.json());
app.post('/building/', function (req, res) {
'use strict';
var myObject = null;
var callSiteApi = {
uri: 'http://localhost:8080/site/',
body: JSON.stringify(req.body),
method: 'POST',
headers: {
'Content-Type': 'application/json'
}
}
// First External API Call
Request(callSiteApi, function (error, response) {
if (error) {
console.log('ERROR with user request.');
return response.sendStatus(500); // Return back that an error occurred
} else {
// Get data from response.body
var materialquerystring = "mat="+response.body.material+"&date="+response.body.date;
var floor = response.body.floor;
for (var i = 0; i < floor.length; i++) {
matereialValueURL = "http://localhost:8080/material/q="+materialquerystring;
// Second External API Call within for loop
Request.get(materialValueURL, (error, response, body) => {
if (error) {
console.log(req.error);
}
materialObject = JSON.parse(body);
var valuequerystring = "value="+materialObject.value;
// do somehting with materialObject
console.log("first request iteration =" + i);
sitevalueURL = "http://localhost:8080/value/q="+valuequerystring;
// Third External API Call within for loop
Request.get(sitevalueURL, (error, response, body) => {
if (error) {
logger.debug('[' + pid + '] ' + req.error);
//return console.dir(error);
}
valueObject = JSON.parse(body);
console.log("second request iteration =" + i);
// do somehting with valueObject 7 materialObject
var a = materialObject.a;
var b = valueObject.b;
var c = a+b;
});
});
}
res.writeHead(200, {
'Content-Type': 'application/json'
});
res.end('{"value-1":"a","value-2":"b","value-3":"c","material":"materialquerystring","value":"valuequerystring"}');
}
});
});如果您只需要从用户的请求中获取一个数字，然后多次发出相同的 http 请求，则应该这样做。我带来了一个pointfreemap助手从直列四缸，使事情变得更容易一些。
您可能需要在这里和那里进行一些调整，特别是在最后then条款中
const map = require('crocks/pointfree/map');
const app = express();
app.use(bodyParser.json());
const range = integer => [...new Array(integer).keys()]
const replicate = (i, x) => range(i).fill(x)
const handleError = error => {
logger.debug(`['${pid}'] ${error.reponse.error}`)
return error;
}
const getMaterialURIs = response =>
replicate(response.body.floor.length, `http://localhost:8080/material/q=${response.body.material}`)
const processMaterialResponse = response => {
doSomethingWithMaterial(response.body)
return response;
}
const getSiteValueURI = response =>
`http://localhost:8080/value/q=${response.body.value}`;
const processSiteValueResponse = response => {
doSomethingWithSiteValue(response.body)
return response;
}
app.post('/building/', function (req, res) {
const uri = 'http://localhost:8080/site/';
const body = JSON.stringify(req.body);
const method = 'POST';
const headers = { 'Content-Type': 'application/json' };
// First External API Call
Request({uri, body, method, headers})
// 1: fetch to derive the material URI
.then(getMaterialURIs)
// 2: fetch from that material URI
.then(map(Request.get))
.then(Promise.all)
// 3: process the material response
.then(map(processMaterialResponse))
// 4: derive the siteValueURI
.then(map(getSiteValueURI))
// 5: fetch the siteValueURI
.then(map(Request.get))
.then(Promise.all)
// 6: process the site value response
.then(map(processSiteValueResponse))
.catch(handleError)
.then(response => {
res.writeHead(200, { 'Content-Type': 'application/json' });
res.end('{"material":"materialquerystring","value":"valuequerystring"}');
});
});
本文收集自互联网，转载请注明来源。
如有侵权，请联系 [email protected] 删除。
我来说两句