How can I send the response.body out of request module function? - node.js

Question

I started by creating a return statement in the request function (I have linked a picture) and then console.log it outside of the function but that didn't work out.
My server code
var options = {
'method': 'POST',
'url': 'http://localhost:8080/ES_Part1/api/user/getUser',
'headers': {
'Content-Type': 'application/x-www-form-urlencoded'
},
form: {
'username': username,
'password': password
}
};
requestToApi(options, function(error, response) {
if (error) throw new Error(error);
console.log("Send form data to remote api and to return the user from Spring")
console.log(response.body);
return response.body
});
var fromapi = response.body;
res.end();
Example:

Answer 1

I suggest you use a Promise-based approach here rather than the callback-style that you're using for requestToApi. If you're using the request package, there is a Promise-based version available.
Alternative solution would be to create a promise yourself, like such:
var requestToApiAsPromise = (options) => {
return new Promise((resolve, reject) => {
requestToApi(options, (error, response) => {
if (error) {
reject(error)
return
}
resolve(response.body)
})
})
}
Then you can use this method in your middleware:
app.post("/checkUser", (req, res) => {
async function process() {
try {
var username = req.body.username
var password = req.body.password
var options = {...}
var response = await requestToApiAsPromise(options)
// response => response.body
// do whatever
res.end()
} catch (error) {
next(error)
}
}
process()
})
This method uses async/await so that it lets you write your code as if you were doing things synchronously, so it's making it easier to make asynchronous calls and have them "wait" before the next line gets executed.

Answer 2

👨‍🏫 If you want to get respose.body outside the handler, than you can use this code below 👇:
// an example get function
app.get('/users', async(req, res) => {
var options = {
'method': 'POST',
'url': 'http://localhost:8080/ES_Part1/api/user/getUser',
'headers': {
'Content-Type': 'application/x-www-form-urlencoded'
},
form: {
'username': username,
'password': password
}
};
const result = new Promise((resolve, reject) => {
requestToApi(options, function(error, response) {
if (error) return reject(error);
return resolve(JSON.parse(response.body));
});
})
// make sure, to use async in your function
// because we're using await here
var fromapi = await result;
// It's working here
console.log(fromapi);
res.end();
})
That code above 👆, only an example that you can use to read response.body. If you want to handle the error from that code above, you can use like this code below:
try {
// make sure, to use async in your function
// because we're using await here
var fromapi = await result;
// It's working here
console.log(fromapi);
} catch(ex) {
// print error response
console.log(ex.message);
}
I hope it's can help you 🙏.