[BugFix] Fix MySQL 8.0.x compatibility problem

[Zac-saodiseng]

Why I'm doing:

1. Connect to the Cluster via IntelliJ (might occur on other database management tools) using a compatible 8.0.x MySQL driver
2. Attempt to refresh the Schema in the Database UI
3. Exception being thrown when trying to scan the schema using the MySQL 8.0.33 driver:

Connection Error
[HY000][1193] Getting analyzing error. Detail message:
Unknown system variable 'default_storage_engine', the
most similar variables are {'default_rowset_type',
'default_table_compression', 'enable_sort_aggregate'}.

Connection Error
Getting analyzing error. Detail message:
Column 'subpartition_ordinal_position' cannot
be resolved.
and 1 duplicate report.

Getting analyzing error. Detail message:
Unknown table 'information_schema.applicable_roles'.

Connection Error
Unknown compression type (0) backend [id=10002].

Getting analyzing error. Detail message:
Column expression cannot be resolved.

Getting analyzing error. Detail message:
Column 'c.enforced' cannot be resolved.

Getting analyzing error. Detail message:
Column 'subpartition_ordinal_position' cannot be resolved.
and 9 duplicate reports.

What I'm doing:

1. Need to add INFORMATION_SCHEMA.APPLICABLE_ROLES table.
2. Need to add the system variable 'default_storage_engine' and 'default_table_compression'.
3. Need to add the column 'EXPRESSION' in INFORMATION_SCHEMA.STATISTICS and 'ENFORCED' in INFORMATION_SCHEMA.TABLE_CONSTRAINTS(isGrantable features are not currently supported, but will be gradually supported in the future).

mysql> select * from applicable_roles ;
+------+------+---------+--------------+-----------+-----------+--------------+------------+--------------+
| USER | HOST | GRANTEE | GRANTEE_HOST | ROLE_NAME | ROLE_HOST | IS_GRANTABLE | IS_DEFAULT | IS_MANDATORY |
+------+------+---------+--------------+-----------+-----------+--------------+------------+--------------+
| root | %    | root    | %            | root      | %         | NO           | NO        | NO           |
+------+------+---------+--------------+-----------+-----------+--------------+------------+--------------+
1 row in set (0.07 sec)

Fixes #55629

What type of PR is this:

• BugFix
• Feature
• Enhancement
• Refactor
• UT
• Doc
• Tool

Does this PR entail a change in behavior?

• Yes, this PR will result in a change in behavior.
• No, this PR will not result in a change in behavior.

If yes, please specify the type of change:

• Interface/UI changes: syntax, type conversion, expression evaluation, display information
• Parameter changes: default values, similar parameters but with different default values
• Policy changes: use new policy to replace old one, functionality automatically enabled
• Feature removed
• Miscellaneous: upgrade & downgrade compatibility, etc.

Checklist:

• I have added test cases for my bug fix or my new feature
• This pr needs user documentation (for new or modified features or behaviors)
  • I have added documentation for my new feature or new function
• This is a backport pr

Bugfix cherry-pick branch check:

• I have checked the version labels which the pr will be auto-backported to the target branch
  • 3.4
  • 3.3
  • 3.2
  • 3.1
  • 3.0

[starrocks-cr]

The most risky bug in this code is:
Potential out-of-bounds access due to _column_num being uninitialized, leading to unpredictable slot_id validation.

You can modify the code like this:

// Within SchemaApplicableRolesScanner constructor or initialization part:
_column_num = sizeof(_s_columns) / sizeof(SchemaScanner::ColumnDesc); // Initialize _column_num

// Ensure to include this initialization logic to avoid potential issues.
SchemaScanner::SchemaScanner(_s_columns, _column_num);

[starrocks-cr]

The most risky bug in this code is:
Improper handling of lock acquisition and release order might lead to deadlocks. Specifically, mixing userReadLock/Unlock with roleReadLock/Unlock without a consistent order can cause deadlock issues if another method acquires them in a conflicting order.

You can modify the code like this:

public List<RolePrivilegeCollectionV2> getApplicableRoles(UserIdentity user) throws PrivilegeException {
    List<RolePrivilegeCollectionV2> applicableRoles = new ArrayList<>();
    
    // Ensure a consistent locking order by acquiring role lock before user lock
    roleReadLock();
    try {
        userReadLock();
        try {
            Set<Long> roleIds = getRoleIdsByUser(user);
            for (Long roleId : roleIds) {
                RolePrivilegeCollectionV2 rolePrivilegeCollection = roleIdToPrivilegeCollection.get(roleId);
                if (rolePrivilegeCollection != null) {
                    applicableRoles.add(rolePrivilegeCollection);
                }
            }
        } finally {
            userReadUnlock();
        }
    } finally {
        roleReadUnlock();
    }
    return applicableRoles;
}

This modification ensures that locks are always acquired and released in a consistent order, mitigating the risk of deadlocks.

[starrocks-cr]

The most risky bug in this code is: If getAuthDbRequestResult(request.getAuth_info()) returns a null value for authorizedDbs, calling isEmpty() on it will result in a NullPointerException.

You can modify the code like this:

public static TGetApplicableRolesResponse generateApplicableRolesResp(TGetApplicableRolesRequest request) throws TException {
    TGetApplicableRolesResponse response = new TGetApplicableRolesResponse();
    List<TApplicableRolesInfo> roleList = new ArrayList<>();

    AuthDbRequestResult result = getAuthDbRequestResult(request.getAuth_info());

    if (result == null || result.authorizedDbs == null || result.authorizedDbs.isEmpty()) {
        response.setRoles(roleList);
        return response;
    }

    UserIdentity currentUser = result.currentUser;
    if (currentUser == null) {
        response.setRoles(roleList);
        return response;
    }

    AuthorizationMgr authMgr = GlobalStateMgr.getCurrentState().getAuthorizationMgr();
    try {
        for (RolePrivilegeCollectionV2 role : authMgr.getApplicableRoles(currentUser)) {
            String roleName = role.getName();
            String roleHost = "%";

            String isGrantable = authMgr.isRoleGrantable(currentUser, roleName) ? "YES" : "NO";
            String isDefault = authMgr.isRoleDefault(currentUser, roleName) ? "YES" : "NO";
            String isMandatory = authMgr.isRoleMandatory(currentUser, roleName) ? "YES" : "NO";

            TApplicableRolesInfo roleInfo = new TApplicableRolesInfo();
            roleInfo.setUser(currentUser.getUser());
            roleInfo.setHost(currentUser.getHost());
            roleInfo.setGrantee(currentUser.getUser());
            roleInfo.setGrantee_host(currentUser.getHost());
            roleInfo.setRole_name(roleName);
            roleInfo.setRole_host(roleHost);
            roleInfo.setIs_grantable(isGrantable);
            roleInfo.setIs_default(isDefault);
            roleInfo.setIs_mandatory(isMandatory);

            roleList.add(roleInfo);
        }
    } catch (PrivilegeException e) {
        throw new RuntimeException(e);
    }

    response.setRoles(roleList);
    return response;
}

[imay]

New items should be added to the last.

[Zac-saodiseng]

Thanks, I've already revised it.

[Astralidea]

It should be moved behind 44.

[Astralidea]

It’s best not to add extra persistent fields.

[sonarqubecloud]

Quality Gate failed

Failed conditions
C Reliability Rating on New Code (required ≥ A)

See analysis details on SonarQube Cloud

Catch issues before they fail your Quality Gate with our IDE extension SonarQube for IDE

[github-actions]

[Java-Extensions Incremental Coverage Report]

✅ pass : 0 / 0 (0%)

[github-actions]

[FE Incremental Coverage Report]

✅ pass : 59 / 66 (89.39%)

file detail

	path	covered_line	new_line	coverage	not_covered_line_detail
🔵	com/starrocks/service/InformationSchemaDataSource.java	28	34	82.35%	[622, 623, 628, 629, 656, 657]
🔵	com/starrocks/catalog/system/information/ApplicableRolesSystemTable.java	12	13	92.31%	[25]
🔵	com/starrocks/qe/SessionVariable.java	2	2	100.00%	[]
🔵	com/starrocks/catalog/system/information/InfoSchemaDb.java	1	1	100.00%	[]
🔵	com/starrocks/authorization/AuthorizationMgr.java	12	12	100.00%	[]
🔵	com/starrocks/catalog/system/information/StatisticsSystemTable.java	1	1	100.00%	[]
🔵	com/starrocks/service/FrontendServiceImpl.java	1	1	100.00%	[]
🔵	com/starrocks/catalog/system/information/TableConstraintsSystemTable.java	1	1	100.00%	[]
🔵	com/starrocks/catalog/system/information/PartitionsSystemTableSystemTable.java	1	1	100.00%	[]

[github-actions]

[BE Incremental Coverage Report]

✅ pass : 83 / 92 (90.22%)

file detail

	path	covered_line	new_line	coverage	not_covered_line_detail
🔵	be/src/exec/schema_scanner/schema_applicable_roles_scanner.cpp	78	87	89.66%	[45, 49, 54, 55, 57, 58, 86, 89, 104]
🔵	be/src/exec/schema_scanner.cpp	2	2	100.00%	[]
🔵	be/src/exec/schema_scanner/schema_helper.cpp	2	2	100.00%	[]
🔵	be/src/exec/schema_scanner/schema_applicable_roles_scanner.h	1	1	100.00%	[]

[github-actions]

@Mergifyio backport branch-3.4

[mergify]

backport branch-3.4

✅ Backports have been created

• #57066 [BugFix] Fix MySQL 8.0.x compatibility problem (backport #56872) has been created for branch branch-3.4 but encountered conflicts