BUG#32327411 : OFFLINE KEYRING MIGRATION FROM KEYRING_FILE REPORTS

SUCCESS, BUT MIGRATES NO KEYS

Problem: For empty or non-existing keyring sources, the offline keyring
migration reports success, but no appropriate warning message is shown.
If the user enters a relative path for the --keyring-file-data variable,
the source keyring is looked in the basedir, as offline keyring
migration
doesn't support relative path, entering a relative path might result in
empty keyring source generation, and transferring keys from it.

Fix: Now the migration process will check for any error during the key
fetch
, if there's no error, and there are no keys, then a warning message is
shown that keyring has no keys in it.
The test will try to migrate the keys from an empty keyring source, and
looks for the warning message in the server log.

RB#27401

Author: shussinh

share/messages_to_error_log.txt

@@ -11587,6 +11587,9 @@ ER_INVALID_TLS_VERSION
 ER_RPL_RELAY_LOG_RECOVERY_GTID_ONLY
   eng "Relay log recovery on channel with GTID_ONLY=1. The channel will switch to a new relay log and the GTID protocol will be used to replicate unapplied transactions."
 
+ER_WARN_MIGRATION_EMPTY_SOURCE_KEYRING
+  eng "Source keyring does not have any keys to migrate."
+
 # DO NOT add server-to-client messages here;
 # they go in messages_to_clients.txt
 # in the same directory as this file.

sql/migrate_keyring.cc

@@ -498,6 +498,12 @@ bool Migrate_keyring::fetch_and_store_keys() {
     if (key) my_free((char *)key);
     if (key_type) my_free(key_type);
   }
+
+  /* If there are zero keys in the keyring, it means no keys were migrated */
+  if (!error && m_source_keys.size() == 0) {
+    LogErr(WARNING_LEVEL, ER_WARN_MIGRATION_EMPTY_SOURCE_KEYRING);
+  }
+
   if (error) {
     /* something went wrong remove keys from destination plugin. */
     while (m_source_keys.size()) {