Checkpoint: Remplacement complet de imap 0.8 par ImapFlow : OAuth2 moderne avec jeton brut, TLS strict, traitement séquentiel des messages non lus, verrou anti-concurrence conservé, marquage Seen uniquement après succès, test de connexion adapté, diagnostic OAuth2 et tests unitaires ajoutés. Validation : 31 tests, TypeScript, build et authentification réelle Microsoft 365 réussis.

scripts/test-imapflow-oauth.mjs

@@ -0,0 +1,49 @@
+import { ImapFlow } from "imapflow";
+
+const required = (name) => {
+  const value = process.env[name];
+  if (!value) throw new Error(`Variable ${name} manquante`);
+  return value;
+};
+
+const tenantId = required("AZURE_AD_TENANT_ID");
+const clientId = required("AZURE_AD_CLIENT_ID");
+const clientSecret = required("AZURE_AD_CLIENT_SECRET");
+const email = required("IMAP_TEST_EMAIL");
+const host = process.env.IMAP_TEST_HOST || "outlook.office365.com";
+
+const response = await fetch(
+  `https://login.microsoftonline.com/${tenantId}/oauth2/v2.0/token`,
+  {
+    method: "POST",
+    headers: { "Content-Type": "application/x-www-form-urlencoded" },
+    body: new URLSearchParams({
+      client_id: clientId,
+      client_secret: clientSecret,
+      scope: "https://outlook.office365.com/.default",
+      grant_type: "client_credentials",
+    }),
+  },
+);
+const tokenResponse = await response.json();
+if (!response.ok || !tokenResponse.access_token) {
+  throw new Error(`Échec OAuth2 : ${tokenResponse.error || response.status}`);
+}
+
+const client = new ImapFlow({
+  host,
+  port: 993,
+  secure: true,
+  auth: { user: email, accessToken: tokenResponse.access_token },
+  tls: { servername: host, rejectUnauthorized: true },
+  verifyOnly: true,
+  logger: false,
+});
+
+try {
+  await client.connect();
+  console.log(`Authentification ImapFlow OAuth2 réussie pour ${email}`);
+} finally {
+  if (client.usable) await client.logout().catch(() => client.close());
+  else client.close();
+}