fix if user does not exist, desc user xxx will be raise "User not e…

…xisted!" (vesoft-inc#2450)

If user does not exist `desc user xxx` will be raise "User not existed!"

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## What type of PR is this?
- [x] bug
- [ ] feature
- [ ] enhancement

## What problem(s) does this PR solve?
#### Issue(s) number: 
Close vesoft-inc#5141

#### Description:
If use does not exist `desc user xxx` will be raise "User not existed!"

## How do you solve it?
add account exist verify in meta service

## Special notes for your reviewer, ex. impact of this fix, design document, etc:

## Checklist:
Tests:
manunal test:
```
(root@nebula) [(none)]> desc user u6
[ERROR (-1005)]: User not existed!

Wed, 15 Feb 2023 22:43:06 CST
```
- [ ] Unit test(positive and negative cases)
- [ ] Function test
- [ ] Performance test
- [ ] N/A

Affects:
- [ ] Documentation affected (Please add the label if documentation needs to be modified.)
- [ ] Incompatibility (If it breaks the compatibility, please describe it and add the label.）
- [ ] If it's needed to cherry-pick (If cherry-pick to some branches is required, please label the destination version(s).)
- [ ] Performance impacted: Consumes more CPU/Memory


## Release notes:

Please confirm whether to be reflected in release notes and how to describe:
> ex. Fixed the bug .....


Migrated from vesoft-inc#5345

Co-authored-by: Milittle <[email protected]>

src/meta/processors/user/AuthenticationProcessor.cpp

@@ -449,10 +449,23 @@ void GetUserRolesProcessor::process(const cpp2::GetUserRolesReq& req) {
   folly::SharedMutex::ReadHolder holder(LockUtils::lock());
   const auto& act = req.get_account();
 
+  auto retCode = userExist(act);
+  if (retCode != nebula::cpp2::ErrorCode::SUCCEEDED) {
+    if (retCode == nebula::cpp2::ErrorCode::E_USER_NOT_FOUND) {
+      LOG(INFO) << "Get User Roles Failed: " << act << " not found.";
+    } else {
+      LOG(INFO) << "Get User Roles Failed, User " << act
+                << " error: " << apache::thrift::util::enumNameSafe(retCode);
+    }
+    handleErrorCode(retCode);
+    onFinished();
+    return;
+  }
+
   auto prefix = MetaKeyUtils::rolesPrefix();
   auto ret = doPrefix(prefix);
   if (!nebula::ok(ret)) {
-    auto retCode = nebula::error(ret);
+    retCode = nebula::error(ret);
     LOG(INFO) << "Prefix roles failed, error: " << apache::thrift::util::enumNameSafe(retCode);
     handleErrorCode(retCode);
     onFinished();

tests/tck/features/user/User.feature

@@ -143,12 +143,11 @@ Feature: User & privilege Test
       DROP USER IF EXISTS u6;
       """
     Then the execution should be successful
-    # TODO(shylock) fix it
-    # When executing query:
-    # """
-    # DESC USER u6;
-    # """
-    # Then a ExecutionError should be raised at runtime: User not existed!
+    When executing query:
+      """
+      DESC USER u6;
+      """
+    Then a ExecutionError should be raised at runtime: User not existed!
     When executing query:
       """
       DROP USER IF EXISTS u6;
@@ -186,12 +185,11 @@ Feature: User & privilege Test
       DROP USER user_mlt_roles;
       """
     Then the execution should be successful
-    # TODO(shylock) fix me
-    # When executing query:
-    # """
-    # DESC USER user_mlt_roles
-    # """
-    # Then a ExecutionError should be raised at runtime: User not existed!
+    When executing query:
+      """
+      DESC USER user_mlt_roles
+      """
+    Then a ExecutionError should be raised at runtime: User not existed!
     When executing query:
       """
       CREATE USER user_mlt_roles;
@@ -731,8 +729,7 @@ Feature: User & privilege Test
       """
       DESC USER user_not_exist
       """
-    Then the result should be, in any order, with relax comparison:
-      | role | space |
+    Then a ExecutionError should be raised at runtime: User not existed!
     When executing query with user "user1" and password "pwd1":
       """
       DESC USER user1
@@ -766,6 +763,11 @@ Feature: User & privilege Test
       DESC USER root
       """
     Then a PermissionError should be raised at runtime:
+    When executing query:
+      """
+      DESCRIBE USER not_exists
+      """
+    Then a ExecutionError should be raised at runtime: User not existed!
     When executing query:
       """
       DROP SPACE IF EXISTS user_tmp_space_4;
@@ -848,10 +850,3 @@ Feature: User & privilege Test
       """
     Then a SyntaxError should be raised at runtime: syntax error near `xxx'
     When verify login with user "user_ip4" and password "pwd1"
-
-# TODO(shylock) fix it
-# When executing query:
-# """
-# DESCRIBE USER not_exists
-# """
-# Then a ExecutionError should be raised at runtime: User not existed!