From b7eb935f10eb3d90a1fdf925870e366b46794367 Mon Sep 17 00:00:00 2001
From: Kexiang Wang <kx.wang@hotmail.com>
Date: Mon, 26 Feb 2024 21:53:31 -0500
Subject: [PATCH] fix

---
 e2e_test/error_ui/simple/main.slt | 24 ++++++++++++++++++++++++
 src/expr/udf/src/external.rs      |  2 ++
 2 files changed, 26 insertions(+)

diff --git a/e2e_test/error_ui/simple/main.slt b/e2e_test/error_ui/simple/main.slt
index da44dfa70a1e6..57876139183ac 100644
--- a/e2e_test/error_ui/simple/main.slt
+++ b/e2e_test/error_ui/simple/main.slt
@@ -8,6 +8,30 @@ Caused by:
 Near "selet"
 
 
+statement error
+create function int_42() returns int as int_42 using link 'remotehost:8815';
+----
+db error: ERROR: Failed to run the query
+
+Caused by:
+  Flight service error: failed to create LoadBalancedChannel, address: remotehost:8815, err: failed to resolve IPs: Failed to resolve ServiceDefinition: failed to resolve ips from host: no record found for Query { name: Name("remotehost."), query_type: AAAA, query_class: IN }
+
+
+statement error
+create function int_42() returns int as int_42 using link '55.55.55.55:5555';
+----
+db error: ERROR: Failed to run the query
+
+Caused by these errors (recent errors listed first):
+  1: failed to check UDF signature
+  2: failed to send requests to UDF service
+  3: status: Unavailable, message: "error trying to connect: tcp connect error: deadline has elapsed", details: [], metadata: MetadataMap { headers: {} }
+  4: transport error
+  5: error trying to connect
+  6: tcp connect error
+  7: deadline has elapsed
+
+
 statement error
 alter system set not_exist_key to value;
 ----
diff --git a/src/expr/udf/src/external.rs b/src/expr/udf/src/external.rs
index f713ae34a1278..845429ef129a1 100644
--- a/src/expr/udf/src/external.rs
+++ b/src/expr/udf/src/external.rs
@@ -33,7 +33,9 @@ use tonic::transport::Channel;
 use crate::metrics::GLOBAL_METRICS;
 use crate::{Error, Result};
 
+/// Used for lazy udf client connections
 const DNS_PROBE_INTERVAL_SECS: u64 = 5;
+/// Used for eager udf client connections
 const EAGER_DNS_PROBE_INTERVAL_SECS: u64 = 5;
 const REQUEST_TIMEOUT_SECS: u64 = 5;
 const CONNECT_TIMEOUT_SECS: u64 = 5;