refactor(query): Gracefully handle unknown GrantEntry objects in UserGrantSet::from_pb (#18400)

* fix(query): Gracefully handle unknown GrantEntry objects in UserGrantSet::from_pb

When an older version of the application processes `UserGrantSet` data that
contains `GrantEntry` objects with newly introduced `GrantObject` types, the
`GrantEntry::from_pb` conversion can fail for those specific entries.

This commit modifies the `UserGrantSet::from_pb` function to gracefully
handle such scenarios. If `GrantEntry::from_pb` returns an error (e.g.,
due to an unknown `GrantObject`), the error is now logged, and the
problematic grant entry is skipped instead of causing the entire
conversion to fail.

This ensures that users on older versions can still log in and use
their available grants, providing better forward compatibility and
robustness against evolving data schemas.
Without this, a user attempting to log in with data containing new
`GrantObject` types would be prevented from logging in on an older client.

* make err msg more detial

Author: TCeason

Cargo.lock

@@ -16,6 +16,7 @@ databend-common-meta-types = { workspace = true }
 databend-common-protos = { workspace = true }
 enumflags2 = { workspace = true }
 fastrace = { workspace = true }
+log = { workspace = true }
 num = { workspace = true }
 prost = { workspace = true }
 thiserror = { workspace = true }

src/meta/proto-conv/Cargo.toml

@@ -160,7 +160,7 @@ impl FromToProto for mt::principal::GrantObject {
         reader_check_msg(p.ver, p.min_reader_ver)?;
 
         let Some(object) = p.object else {
-            return Err(Incompatible::new("GrantObject cannot be None".to_string()));
+            return Err(Incompatible::new(format!("Incompatible GrantObject type: Data contains an unrecognized variant for {} version", p.ver)));
         };
 
         match object {
@@ -295,7 +295,13 @@ impl FromToProto for mt::principal::UserGrantSet {
 
         let mut entries = Vec::new();
         for entry in p.entries.iter() {
-            entries.push(mt::principal::GrantEntry::from_pb(entry.clone())?);
+            // If we add new GrantObject in new version
+            // Rollback to old version, GrantEntry.object will be None
+            // GrantEntry::from_pb will return err so user can not login in old version.
+            match mt::principal::GrantEntry::from_pb(entry.clone()) {
+                Ok(entry) => entries.push(entry),
+                Err(e) => log::error!("GrantEntry::from_pb with error : {e}"),
+            }
         }
         let mut roles = HashSet::new();
         for role in p.roles.iter() {