OSIS-165: cap getCredentials access-denied recovery to a single retry

osis-core/src/main/java/com/scality/osis/service/impl/ScalityOsisServiceImpl.java

@@ -1262,30 +1262,44 @@ public AnonymousUser getAnonymousUser() {
      * @return the credentials
      */
     public Credentials getCredentials(String accountID) {
-        Credentials credentials = null;
         try {
-            AssumeRoleRequest assumeRoleRequest = ScalityModelConverter.getAssumeRoleRequestForAccount(accountID,
-                    appEnv.getAssumeRoleName());
-            logger.debug("[Vault] Assume Role request:{}", assumeRoleRequest);
-            credentials = vaultAdmin.getTempAccountCredentials(assumeRoleRequest);
-            logger.debug("[Vault] Assume Role response received with access key:{}, expiration:{}",
-                    credentials.getAccessKeyId(), credentials.getExpiration());
+            return assumeRole(accountID);
         } catch (VaultServiceException e) {
+            if (!isAccessDenied(e)) {
+                throw e;
+            }
+            // if access denied, the osis role is not provisioned yet: set it up and retry once
+            logger.error(e.getReason() + ". Recreating the role");
+            // Call get Account with Account ID to retrieve account name
+            AccountData account = vaultAdmin.getAccount(ScalityModelConverter.toGetAccountRequestWithID(accountID));
+            asyncScalityOsisService.setupAssumeRole(accountID, account.getName());
 
-            if (!StringUtils.isNullOrEmpty(e.getErrorCode()) &&
-                    ACCESS_DENIED.equals(e.getErrorCode())) {
-                // if access denied, invoke setupAssumeRole
-                logger.error(e.getReason() + ". Recreating the role");
-                // Call get Account with Account ID to retrieve account name
-                AccountData account = vaultAdmin.getAccount(ScalityModelConverter.toGetAccountRequestWithID(accountID));
-                asyncScalityOsisService.setupAssumeRole(accountID, account.getName());
-                return getCredentials(accountID);
+            try {
+                return assumeRole(accountID);
+            } catch (VaultServiceException retryError) {
+                if (isAccessDenied(retryError)) {
+                    logger.error("Assume role still access-denied for account {} after recreating the role; "
+                            + "giving up to avoid unbounded retries", accountID);
+                }
+                throw retryError;
             }
-            throw e;
         }
+    }
+
+    private Credentials assumeRole(String accountID) {
+        AssumeRoleRequest assumeRoleRequest = ScalityModelConverter.getAssumeRoleRequestForAccount(accountID,
+                appEnv.getAssumeRoleName());
+        logger.debug("[Vault] Assume Role request:{}", assumeRoleRequest);
+        Credentials credentials = vaultAdmin.getTempAccountCredentials(assumeRoleRequest);
+        logger.debug("[Vault] Assume Role response received with access key:{}, expiration:{}",
+                credentials.getAccessKeyId(), credentials.getExpiration());
         return credentials;
     }
 
+    private boolean isAccessDenied(VaultServiceException e) {
+        return !StringUtils.isNullOrEmpty(e.getErrorCode()) && ACCESS_DENIED.equals(e.getErrorCode());
+    }
+
     /**
      * Create osis credential osis s 3 credential.
      *

osis-core/src/test/java/com/scality/osis/service/impl/ScalityOsisServiceMiscTests.java

@@ -26,7 +26,7 @@
 import java.util.List;
 import java.util.Optional;
 
-import static com.scality.osis.utils.ScalityConstants.IAM_PREFIX;
+import static com.scality.osis.utils.ScalityConstants.*;
 import static com.scality.osis.utils.ScalityTestUtils.*;
 import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
@@ -471,6 +471,25 @@ void testGetCredentials400() {
         // Verify the results
     }
 
+    @Test
+    void testGetCredentialsStopsRetryingWhenAccessDeniedPersists() {
+        // Setup: every assume-role attempt returns access-denied (persistent Vault misconfiguration)
+        when(vaultAdminMock.getTempAccountCredentials(any(AssumeRoleRequest.class)))
+                .thenThrow(new VaultServiceException(HttpStatus.FORBIDDEN, ACCESS_DENIED,
+                        "User: backbeat is not allowed to assume role"));
+
+        // Run the test: persistent access-denied must surface as a VaultServiceException, not recurse forever
+        final VaultServiceException error = assertThrows(VaultServiceException.class,
+                () -> scalityOsisServiceUnderTest.getCredentials(TEST_TENANT_ID));
+
+        // Verify the results
+        assertEquals(ACCESS_DENIED, error.getErrorCode(), "Invalid Error Code");
+        // recovery routine (setupAssumeRole) is reached exactly once: it looks up the account name once
+        verify(vaultAdminMock, times(1)).getAccount(any(GetAccountRequestDTO.class));
+        // exactly one recovery means one original attempt plus one retry, no unbounded recursion
+        verify(vaultAdminMock, times(2)).getTempAccountCredentials(any(AssumeRoleRequest.class));
+    }
+
     @Test
     void testSetupAssumeRoleAsync() {