tools/offline_log_viewer: added decode_adl_or_serde to dispatch decod…

…ing functions

tools/offline_log_viewer/controller.py

@@ -173,7 +173,6 @@ def decode_feature_update_action(r):
         cmd['type_name'] = 'unknown'
     return cmd
 
-
 def decode_cluster_bootstrap_command(record):
     def decode_user_and_credential(r):
         user_cred = {}
@@ -201,6 +200,18 @@ def decode_user_and_credential(r):
 
     return cmd
 
+def decode_adl_or_serde(record, adl_fn, serde_fn):
+    rdr = Reader(BufferedReader(BytesIO(record.value)))
+    k_rdr = Reader(BytesIO(record.key))
+    either_adl_or_serde = rdr.peek_int8()
+    assert either_adl_or_serde >= -1, "unsupported serialization format"
+    if either_adl_or_serde == -1:
+        # serde encoding flag, consume it and proceed
+        rdr.skip(1)
+        return serde_fn(k_rdr, rdr)
+    else:
+        return adl_fn(k_rdr, rdr)
+
 
 def decode_record(batch, record, bin_dump: bool):
     ret = {}