chore: if a txn log is too long, display only the first 5 items (#15392)

Author: drmingdrmer

src/meta/kvapi/src/kvapi/message.rs

@@ -12,9 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use std::fmt;
+use std::fmt::Formatter;
+
 use databend_common_meta_types::Change;
 use databend_common_meta_types::SeqV;
 use databend_common_meta_types::UpsertKV;
+use databend_common_meta_types::VecDisplay;
 
 pub type UpsertKVReq = UpsertKV;
 
@@ -44,6 +48,12 @@ impl MGetKVReq {
     }
 }
 
+impl fmt::Display for MGetKVReq {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", VecDisplay::new_at_most(&self.keys, 5))
+    }
+}
+
 #[derive(serde::Serialize, serde::Deserialize, Clone, Debug, PartialEq, Eq)]
 pub struct ListKVReq {
     pub prefix: String,

src/meta/service/src/api/grpc/grpc_service.rs

@@ -184,7 +184,7 @@ impl MetaServiceImpl {
         let forward_res = self
             .meta_node
             .handle_forwardable_request(forward_req)
-            .info_elapsed(format!("TxnRequest: {:?}", txn))
+            .info_elapsed(format!("TxnRequest: {}", txn))
             .await;
 
         let (endpoint, txn_reply) = match forward_res {

src/meta/types/src/lib.rs

@@ -84,6 +84,7 @@ pub use match_seq::MatchSeq;
 pub use match_seq::MatchSeqExt;
 pub use operation::MetaId;
 pub use operation::Operation;
+pub use proto_display::VecDisplay;
 pub use protobuf::txn_condition;
 pub use protobuf::txn_condition::ConditionResult;
 pub use protobuf::txn_op;

src/meta/types/src/proto_display.rs

@@ -53,10 +53,26 @@ impl<'a, T: Display> Display for OptionDisplay<'a, T> {
     }
 }
 
-struct VecDisplay<'a, T: Display> {
+pub struct VecDisplay<'a, T: Display> {
+    at_most: Option<usize>,
     vec: &'a Vec<T>,
 }
 
+impl<'a, T> VecDisplay<'a, T>
+where T: Display
+{
+    pub fn new(vec: &'a Vec<T>) -> Self {
+        VecDisplay { at_most: None, vec }
+    }
+
+    pub fn new_at_most(vec: &'a Vec<T>, at_most: usize) -> Self {
+        VecDisplay {
+            at_most: Some(at_most),
+            vec,
+        }
+    }
+}
+
 impl<'a, T: Display> Display for VecDisplay<'a, T> {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         write!(f, "[")?;
@@ -66,6 +82,13 @@ impl<'a, T: Display> Display for VecDisplay<'a, T> {
                 write!(f, ",")?;
             }
 
+            if let Some(at_most) = self.at_most {
+                if i >= at_most {
+                    write!(f, "...")?;
+                    break;
+                }
+            }
+
             write!(f, "{}", t)?;
         }
 
@@ -78,13 +101,9 @@ impl Display for TxnRequest {
         write!(
             f,
             "TxnRequest{{ if:{} then:{} else:{} }}",
-            VecDisplay {
-                vec: &self.condition
-            },
-            VecDisplay { vec: &self.if_then },
-            VecDisplay {
-                vec: &self.else_then
-            },
+            VecDisplay::new_at_most(&self.condition, 5),
+            VecDisplay::new_at_most(&self.if_then, 5),
+            VecDisplay::new_at_most(&self.else_then, 5),
         )
     }
 }
@@ -189,9 +208,7 @@ impl Display for TxnReply {
             f,
             "TxnReply{{ success: {}, responses: {}, error: {}}}",
             self.success,
-            VecDisplay {
-                vec: &self.responses
-            },
+            VecDisplay::new_at_most(&self.responses, 5),
             self.error
         )
     }
@@ -263,3 +280,29 @@ impl Display for TxnDeleteByPrefixResponse {
         )
     }
 }
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_vec_display() {
+        assert_eq!(
+            format!("{}", super::VecDisplay::new(&vec![1, 2, 3])),
+            "[1,2,3]"
+        );
+
+        assert_eq!(
+            format!("{}", super::VecDisplay::new_at_most(&vec![1, 2, 3], 3)),
+            "[1,2,3]"
+        );
+
+        assert_eq!(
+            format!("{}", super::VecDisplay::new_at_most(&vec![1, 2, 3, 4], 3)),
+            "[1,2,3,...]"
+        );
+
+        assert_eq!(
+            format!("{}", super::VecDisplay::new_at_most(&vec![1, 2, 3, 4], 0)),
+            "[...]"
+        );
+    }
+}