In an Azure Function as a backend for my webpage, I requested an Azure AD publisher’s authorization token as per this page instructed. This is the line of codes of my Azure Functions:
// Stringfy request body
const postData = querystring.stringify({
'grant_type': 'client_credentials',
'client_id': client_id,
'client_secret': client_secret,
'resource': resource,
});
// Initiate options
var httpAgent = new http.Agent();
httpAgent.maxSockets = 200;
const options = {
hostname: 'login.microsoftonline.com',
path: `/${tenantId}/oauth2/token`,
method: 'POST',
headers: {
'Content-Type': 'application/x-www-form-urlencoded',
},
agent: httpAgent,
}
const tokenReq = http.request(options, (res) => {
console.log(`STATUS: ${res.statusCode}`);
console.log(`HEADERS: ${JSON.stringify(res.headers)}`);
res.setEncoding('utf-8')
res.on('data', (chunk) => {
console.log(chunk);
body += chunk;
});
res.on('end', () => {
console.log('No more data in response.');
console.log("body:" + body);
context.res = {
status: 200,
body: body,
};
});
});
tokenReq.on('error', (e) => {
console.log(`problem with request: ${e.message}`);
context.res = {
status: 500,
body: `problem with request: ${e.message}`,
}
});
// write data to request body
tokenReq.write(postData);
tokenReq.end();
The expected response was the access token that I require, however running it locally I got STATUS 302, and a header containing a location and some other parameters, as a response. In my understanding STATUS 302 states that the URL is moved temporarily to the location provided in the header. Now, I don’t know what I’m supposed to do, the request that I have to make is supposed to be a POST request so a redirection would not work. I’ve also tried to make a new request after receiving the redirect URL, but I got an error message saying: getaddrinfo ENOTFOUND {redirect URL from header}. What did I do wrong here?
Answer
The 302 error was caused by http module, you use require('http'); and http.request(options, (res).... to do the request, so it shows 302 error.
I suggest you to use var request = require('request'); to do the request, below is my function code for your reference (before use request module, you need to run npm install request to install it first):
module.exports = async function (context, req) {
context.log('JavaScript HTTP trigger function processed a request.');
var result = await generatetoken(context);
context.res = {
body: result
};
}
function generatetoken(context){
var request = require('request');
var options = {
'method': 'POST',
'url': 'https://login.microsoftonline.com/<your tenant id>/oauth2/token',
'headers': {
'Content-Type': 'application/x-www-url-form-urlencoded'
},
form: {
'client_id': 'xxxxxx',
'grant_type': 'client_credentials',
'resource': 'xxxxx',
'client_secret': 'xxxxx'
}
};
return new Promise(function(resolve, reject) {
request(options, function(err, res) {
if (err) {
reject(err);
} else {
context.log(res.body);
resolve(res.body);
}
})
})
}