From ca811facc6c007bd19496da5c0af3d011db81fa3 Mon Sep 17 00:00:00 2001
From: xxchan <xxchan22f@gmail.com>
Date: Tue, 2 Jul 2024 23:16:20 +0800
Subject: [PATCH] fix debezium

Signed-off-by: xxchan <xxchan22f@gmail.com>
---
 src/connector/codec/src/decoder/avro/mod.rs      | 3 ++-
 src/connector/codec/src/decoder/mod.rs           | 4 +++-
 src/connector/src/parser/debezium/avro_parser.rs | 8 ++++++++
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/connector/codec/src/decoder/avro/mod.rs b/src/connector/codec/src/decoder/avro/mod.rs
index a001531019759..bafb5cfe4e075 100644
--- a/src/connector/codec/src/decoder/avro/mod.rs
+++ b/src/connector/codec/src/decoder/avro/mod.rs
@@ -337,7 +337,8 @@ impl Access for AvroAccess<'_> {
         let mut options: AvroParseOptions<'_> = self.options.clone();
 
         debug_assert!(
-            path.len() == 1 || (path.len() == 2 && path[0] == "before"),
+            path.len() == 1
+                || (path.len() == 2 && matches!(path[0], "before" | "after" | "source")),
             "unexpected path access: {:?}",
             path
         );
diff --git a/src/connector/codec/src/decoder/mod.rs b/src/connector/codec/src/decoder/mod.rs
index a2823cceca2ff..158c5b532b29d 100644
--- a/src/connector/codec/src/decoder/mod.rs
+++ b/src/connector/codec/src/decoder/mod.rs
@@ -67,7 +67,9 @@ pub trait Access {
     ///
     /// What `path` to access is decided by the CDC layer, i.e., the `FORMAT ...` part (`ChangeEvent`).
     /// e.g.,
-    /// - `DebeziumChangeEvent` accesses `["before", "col_name"]` for value, `["op"]` for op type.
+    /// - `DebeziumChangeEvent` accesses `["before", "col_name"]` for value,
+    ///   `["source", "db"]`, `["source", "table"]` etc. for additional columns' values,
+    ///   `["op"]` for op type.
     /// - `MaxwellChangeEvent` accesses `["data", "col_name"]` for value, `["type"]` for op type.
     /// - In the simplest case, for `FORMAT PLAIN/UPSERT` (`KvEvent`), they just access `["col_name"]` for value, and op type is derived.
     ///
diff --git a/src/connector/src/parser/debezium/avro_parser.rs b/src/connector/src/parser/debezium/avro_parser.rs
index 70e7304c0eea8..04f80ebba1ca1 100644
--- a/src/connector/src/parser/debezium/avro_parser.rs
+++ b/src/connector/src/parser/debezium/avro_parser.rs
@@ -149,6 +149,14 @@ impl DebeziumAvroParserConfig {
         //     "default": null
         // },
         // ...]
+
+        // Other fields are:
+        // - source: describes the source metadata for the event
+        // - op
+        // - ts_ms
+        // - transaction
+        // See <https://debezium.io/documentation/reference/stable/connectors/mysql.html#mysql-events>
+
         avro_schema_to_column_descs(
             avro_schema_skip_nullable_union(avro_extract_field_schema(
                 // FIXME: use resolved schema here.