PKCE による OAuth 承認フローを使用して Azure からアクセス トークンを取得しようとする純粋な Javascript アプリがあります。
アプリは Azure でホストされていません。私は Azure を OAuth 認証サーバーとしてのみ使用しています。
//Based on: https://developer.okta.com/blog/2019/05/01/is-the-oauth-implicit-flow-dead
var config = {
client_id: "xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxx",
redirect_uri: "http://localhost:8080/",
authorization_endpoint: "https://login.microsoftonline.com/{tenant-id}/oauth2/v2.0/authorize",
token_endpoint: "https://login.microsoftonline.com/{tenant-id}/oauth2/v2.0/token",
requested_scopes: "openid api://{tenant-id}/user_impersonation"
};
// PKCE HELPER FUNCTIONS
// Generate a secure random string using the browser crypto functions
function generateRandomString() {
var array = new Uint32Array(28);
window.crypto.getRandomValues(array);
return Array.from(array, dec => ('0' + dec.toString(16)).substr(-2)).join('');
}
// Calculate the SHA256 hash of the input text.
// Returns a promise that resolves to an ArrayBuffer
function sha256(plain) {
const encoder = new TextEncoder();
const data = encoder.encode(plain);
return window.crypto.subtle.digest('SHA-256', data);
}
// Base64-urlencodes the input string
function base64urlencode(str) {
// Convert the ArrayBuffer to string using Uint8 array to convert to what btoa accepts.
// btoa accepts chars only within ascii 0-255 and base64 encodes them.
// Then convert the base64 encoded to base64url encoded
// (replace + with -, replace / with _, trim trailing =)
return btoa(String.fromCharCode.apply(null, new Uint8Array(str)))
.replace(/\+/g, '-').replace(/\//g, '_').replace(/=+$/, '');
}
// Return the base64-urlencoded sha256 hash for the PKCE challenge
async function pkceChallengeFromVerifier(v) {
const hashed = await sha256(v);
return base64urlencode(hashed);
}
// Parse a query string into an object
function parseQueryString(string) {
if (string == "") { return {}; }
var segments = string.split("&").map(s => s.split("="));
var queryString = {};
segments.forEach(s => queryString[s[0]] = s[1]);
return queryString;
}
// Make a POST request and parse the response as JSON
function sendPostRequest(url, params, success, error) {
var request = new XMLHttpRequest();
request.open('POST', url, true);
request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
request.onload = function () {
var body = {};
try {
body = JSON.parse(request.response);
} catch (e) { }
if (request.status == 200) {
success(request, body);
} else {
error(request, body);
}
}
request.onerror = function () {
error(request, {});
}
var body = Object.keys(params).map(key => key + '=' + params[key]).join('&');
request.send(body);
}
function component() {
const element = document.createElement('div');
const btn = document.createElement('button');
element.innerHTML = 'Hello'+ 'webpack';
element.classList.add('hello');
return element;
}
(async function () {
document.body.appendChild(component());
const isAuthenticating = JSON.parse(window.localStorage.getItem('IsAuthenticating'));
console.log('init -> isAuthenticating', isAuthenticating);
if (!isAuthenticating) {
window.localStorage.setItem('IsAuthenticating', JSON.stringify(true));
// Create and store a random "state" value
var state = generateRandomString();
localStorage.setItem("pkce_state", state);
// Create and store a new PKCE code_verifier (the plaintext random secret)
var code_verifier = generateRandomString();
localStorage.setItem("pkce_code_verifier", code_verifier);
// Hash and base64-urlencode the secret to use as the challenge
var code_challenge = await pkceChallengeFromVerifier(code_verifier);
// Build the authorization URL
var url = config.authorization_endpoint
+ "?response_type=code"
+ "&client_id=" + encodeURIComponent(config.client_id)
+ "&state=" + encodeURIComponent(state)
+ "&scope=" + encodeURIComponent(config.requested_scopes)
+ "&redirect_uri=" + encodeURIComponent(config.redirect_uri)
+ "&code_challenge=" + encodeURIComponent(code_challenge)
+ "&code_challenge_method=S256"
;
// Redirect to the authorization server
window.location = url;
} else {
// Handle the redirect back from the authorization server and
// get an access token from the token endpoint
var q = parseQueryString(window.location.search.substring(1));
console.log('queryString', q);
// Check if the server returned an error string
if (q.error) {
alert("Error returned from authorization server: " + q.error);
document.getElementById("error_details").innerText = q.error + "\n\n" + q.error_description;
document.getElementById("error").classList = "";
}
// If the server returned an authorization code, attempt to exchange it for an access token
if (q.code) {
// Verify state matches what we set at the beginning
if (localStorage.getItem("pkce_state") != q.state) {
alert("Invalid state");
} else {
// Exchange the authorization code for an access token
// !!!!!!! This POST fails because of CORS policy.
sendPostRequest(config.token_endpoint, {
grant_type: "authorization_code",
code: q.code,
client_id: config.client_id,
redirect_uri: config.redirect_uri,
code_verifier: localStorage.getItem("pkce_code_verifier")
}, function (request, body) {
// Initialize your application now that you have an access token.
// Here we just display it in the browser.
document.getElementById("access_token").innerText = body.access_token;
document.getElementById("start").classList = "hidden";
document.getElementById("token").classList = "";
// Replace the history entry to remove the auth code from the browser address bar
window.history.replaceState({}, null, "/");
}, function (request, error) {
// This could be an error response from the OAuth server, or an error because the
// request failed such as if the OAuth server doesn't allow CORS requests
document.getElementById("error_details").innerText = error.error + "\n\n" + error.error_description;
document.getElementById("error").classList = "";
});
}
// Clean these up since we don't need them anymore
localStorage.removeItem("pkce_state");
localStorage.removeItem("pkce_code_verifier");
}
}
}());
Azure では、アプリ登録しかありません (アプリ サービスではありません)。
認証コードを取得する最初のステップは機能します。
しかし、アクセス トークンを取得するための POST は失敗します。（写真はこちらから）
オリジン ' http://localhost:8080 ' からの ' https://login.microsoftonline.com/ {tenant-id}/oauth2/v2.0/token'での XMLHttpRequest へのアクセスは、CORS ポリシーによってブロックされました: No 'Access -Control-Allow-Origin' ヘッダーが要求されたリソースに存在します。
アプリ登録の CORS ポリシーは、Azure のどこで構成しますか?