Администратор открывает любой ящик: MAILBOXES → OPEN, полоса «вернуться в admin@»

POST /api/admin/mailboxes/{id}/open — сессия этого ящика без его пароля, только для
MAIL_ADMINS; каждое открытие — в лог (кто какой ящик открыл). В веб-почте: кнопка OPEN
у ящика, сверху розовая полоса «Вы в ящике X как администратор — Back to admin@».
Тесты: +1 (всего 75), ng build OK.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

backend/src/main/java/com/mailserver/controller/MailboxAdminController.java

@@ -3,8 +3,10 @@ package com.mailserver.controller;
 import com.mailserver.config.MailAdmins;
 import com.mailserver.config.MailDomains;
 import com.mailserver.domain.User;
+import com.mailserver.dto.LoginResponse;
 import com.mailserver.service.MailService;
 import com.mailserver.service.UserService;
+import com.mailserver.util.JwtUtils;
 import jakarta.validation.constraints.NotBlank;
 import jakarta.validation.constraints.Size;
 import org.slf4j.Logger;
@@ -66,8 +68,10 @@ public class MailboxAdminController {
     private final MailService mail;
     private final MailDomains domains;
     private final MailAdmins admins;
+    private final JwtUtils jwt;
 
-    public MailboxAdminController(UserService users, MailService mail, MailDomains domains, MailAdmins admins) {
+    public MailboxAdminController(UserService users, MailService mail, MailDomains domains, MailAdmins admins, JwtUtils jwt) {
+        this.jwt = jwt;
         this.users = users;
         this.mail = mail;
         this.domains = domains;
@@ -123,6 +127,21 @@ public class MailboxAdminController {
         });
     }
 
+    /**
+     * Administrator opens a mailbox without its password (Settings → MAILBOXES → Open): a session of that mailbox.
+     * Every opening is logged — who opened which mailbox.
+     */
+    @PostMapping("/{id}/open")
+    public Mono<LoginResponse> open(Mono<Authentication> auth, @PathVariable Long id) {
+        return admin(auth).flatMap(me -> mailbox(id).map(user -> {
+            log.warn("Administrator {} opened mailbox {}", me, user.getEmail());
+            LoginResponse response = new LoginResponse();
+            response.setToken(jwt.generateToken(user.getEmail()));
+            response.setEmail(user.getEmail());
+            return response;
+        }));
+    }
+
     /** Switched off: no login (web, SMTP, IMAP); mail to it is still received. */
     @PutMapping("/{id}/active")
     public Mono<MailboxView> active(Mono<Authentication> auth, @PathVariable Long id, @RequestBody Mono<ActiveRequest> body) {

backend/src/test/java/com/mailserver/controller/MailboxAdminControllerTest.java

@@ -33,7 +33,8 @@ class MailboxAdminControllerTest {
     private final MailService mail = mock(MailService.class);
     private final MailDomains domains = new MailDomains("jambocheck.com", "");
     private final MailAdmins admins = new MailAdmins("", "", domains);
-    private final MailboxAdminController controller = new MailboxAdminController(users, mail, domains, admins);
+    private final com.mailserver.util.JwtUtils jwt = mock(com.mailserver.util.JwtUtils.class);
+    private final MailboxAdminController controller = new MailboxAdminController(users, mail, domains, admins, jwt);
 
     private final User admin = user(1L, "admin@jambocheck.com");
     private final User alice = user(2L, "alice@jambocheck.com");
@@ -43,6 +44,7 @@ class MailboxAdminControllerTest {
         when(users.all()).thenReturn(Flux.just(alice, admin));
         when(users.byId(1L)).thenReturn(Mono.just(admin));
         when(users.byId(2L)).thenReturn(Mono.just(alice));
+        when(users.byId(99L)).thenReturn(Mono.empty());
         when(users.register(anyString(), anyString(), any())).thenAnswer(i -> Mono.just(user(3L, i.getArgument(0))));
         when(users.setPassword(any(), anyString())).thenAnswer(i -> Mono.just((User) i.getArgument(0)));
         when(users.setActive(any(), any(Boolean.class))).thenAnswer(i -> {
@@ -105,6 +107,18 @@ class MailboxAdminControllerTest {
                 .isEqualTo(HttpStatus.BAD_REQUEST);
     }
 
+    @Test
+    void administratorOpensAnyMailboxOthersCanNot() {
+        when(jwt.generateToken("alice@jambocheck.com")).thenReturn("alice-token");
+
+        var session = controller.open(as("admin@jambocheck.com"), 2L).block();
+        assertThat(session.getEmail()).isEqualTo("alice@jambocheck.com");
+        assertThat(session.getToken()).isEqualTo("alice-token");
+
+        assertThat(status(() -> controller.open(as("alice@jambocheck.com"), 1L).block())).isEqualTo(HttpStatus.FORBIDDEN);
+        assertThat(status(() -> controller.open(as("admin@jambocheck.com"), 99L).block())).isEqualTo(HttpStatus.NOT_FOUND);
+    }
+
     private MailboxAdminController.Created create(String me, String email, String password) {
         return controller.create(as(me), Mono.just(new MailboxAdminController.CreateRequest(email, null, password))).block();
     }