如何在NodeJs中使用请求进行多个API调用?
创建一个简单的Node.Js
应用程序,需要显示来自两个API的数据,其中两个API都返回带有ID的多个对象。
需要在单个页面上显示来自这两个API的数据,并且需要根据ID从两个API获取数据。
API 1响应如下所示:
{
"hikes": [
{
"id": 1,
"active": true,
"name": "Mt. Everest",
},
{
"id": 2,
"active": true,
"name": "K2",
},
{
"id": 3,
"active": true,
"name": "Mt. Kinley",
},
]
}
API 2响应如下所示:
{
"hikes": [
{
"id": 1,
"slots": 50,
"available": 23,
},
{
"id": 2,
"slots": 20,
"available": 1,
},
{
"id": 3,
"slots": 43,
"available": 20,
},
]
}
需要同时提取两个API,获取数据并在页面上呈现以显示“名称”,“插槽”和“可用”。
这远远设法拉出一个API,并将数据传递给渲染的index.ejs
页面,但我不知道我应该如何提取第二个API和一些如何获取数据。
我的代码目前看起来像这样:
var port = process.env.PORT || 3000,
express = require("express"),
request = require("request"),
app = express();
app.set("view engine", "ejs");
var hikes = {
url: "",
headers: {
'Identifier': identifier
}
};
var availability = {
url: "",
headers: {
'Identifier': identifier
}
};
app.get("/", function(req, res){
function callback(error, response, body){
if(!error && response.statusCode == 200){
var data = JSON.parse(body);
res.render("index", {data: data});
})
}
}
request(hikes, callback);
});
app.listen(port, function(){
console.log("Running");
});
在我的index.ejs中,我现在创建了一个简单的循环来打印名称:
<% data["hikes"].forEach(function(hike){ %>
<p><%= hike.name %></p>
<% }) %>
关于如何解决这个问题的任何想法?
谢谢!
回答如下:如果我理解正确,我假设您正在尝试从两个API获取数据,并希望根据对象ID将数据合并到单个对象数组中,并将其传递给视图。如果是这种情况,那么您可以使用https://www.npmjs/package/async从两个API并行获取数据,然后将数据合并到一个对象数组中并将其传递给您的视图。以下代码将帮助您了解实现。
var port = process.env.PORT || 3000,
express = require("express"),
request = require("request"),
app = express();
var async = require('async');
app.set("view engine", "ejs");
var hikes = {
url: "https://api/hikes",
headers: {
'Identifier': identifier
}
};
var availability = {
url: "https://api/hikes",
headers: {
'Identifier': identifier
}
};
app.get("/", function(req, res) {
function callback(error, response, body, cb) {
if(error || response.statusCode != 200)
return cb(true);
cb(null, JSON.parse(body).hikes);//instead of sending data directly to view, send it to async callback to merge it latter
}
var tasks = { // tasks to run in parallel
hikes: function (cb) {
request(hikes, function (error, response, body) {
callback(error, response, body, cb);
});
},
availability: function (cb) {
request(availability, function (error, response, body) {
callback(error, response, body, cb);
});
}
};
async.parallel(tasks, function (err, resp) {
if(err) {
//handle error here, the error could be caused by any of the tasks.
return;
}
var availabilityIdMap = resp.availability.map(function (availability) { return availability.id; });//get an array of all the availability ids
var data = resp.hikes.map(function (hike) { //merging hike to corresponding availability object
var availabilityIndex = availabilityIdMap.indexOf(hike.id); // finding the availability against the hike id.
if(availabilityIndex < 0) //availability not found, just return hike
return hike;
var matchingAvailabilityObj = resp.availability[availabilityIndex]; //get the matching availability object
var mergedObj = Object.assign(hike, matchingAvailabilityObj); //merge both objects
return mergedObj;
});
// now the data will have an array of merged object with properties from hike and availability objects
res.render("index", {data: data});
});
});
app.listen(port, function(){
console.log("Running");
});