event: assert DDLEvent.NotSync survives Marshal Unmarshal

[wlwilliamx]

What problem does this PR solve?

Issue Number: close #4419

What is changed and how it works?

• Add a Marshal/Unmarshal round-trip assertion for DDLEvent.NotSync.

Check List

Tests

• Unit test
• Manual test (add detailed scripts or steps below)

Questions

Will it cause performance regression or break compatibility?

No.

Do you need to update user documentation, design documentation or monitoring documentation?

No.

Release note

None

Summary by CodeRabbit

• Bug Fixes
  • Enhanced DDL event handling to properly preserve synchronization state during serialization, ensuring data consistency in event processing.

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 39675055-e469-43da-a31f-fa85885c2e83

📥 Commits

Reviewing files that changed from the base of the PR and between f1451ee and 3f1ae66.

📒 Files selected for processing (1)

• pkg/common/event/ddl_event_test.go

---

📝 Walkthrough

Walkthrough

Adds a NotSync boolean field to the DDLEvent struct and implements a regression test to verify that this field persists through Marshal/Unmarshal serialization cycles, preventing future encoding changes from inadvertently breaking the skip-forward behavior for DDL events.

Changes

Cohort / File(s)	Summary
DDL Event Serialization pkg/common/event/ddl_event.go, pkg/common/event/ddl_event_test.go	Added NotSync boolean field to DDLEvent struct; updated test to verify field survives round-trip serialization/deserialization.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Poem

🐰 A field called NotSync finds its place,
In tests that check serialization's trace,
Marshal and unmarshal, round they go,
The rabbit ensures the skip-skip won't flow! ✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: adding a test assertion for NotSync field serialization/deserialization.
Description check	✅ Passed	The description follows the template with Issue Number, problem statement, changes explanation, test checklist, and release notes all properly completed.
Linked Issues check	✅ Passed	The PR implements the exact solution requested in issue #4419: a Marshal/Unmarshal round-trip unit test that verifies NotSync field survival through encoding/decoding.
Out of Scope Changes check	✅ Passed	All changes are directly related to adding the Marshal/Unmarshal round-trip test for DDLEvent.NotSync as specified in linked issue #4419.

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the robustness of DDL event handling by introducing a specific test case. The change verifies that a critical flag, NotSync, maintains its state across serialization and deserialization processes. This ensures that the system reliably determines which DDL events should be dispatched to downstream sinks, preventing potential inconsistencies in data replication.

Highlights

• DDL Event Serialization: Added a test assertion to ensure that the NotSync field within DDLEvent correctly survives Marshal and Unmarshal operations, which is crucial for dispatchers to properly forward DDL events.

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Changelog

• pkg/common/event/ddl_event_test.go
  • Added a new test case to explicitly set NotSync to true for a DDLEvent.
  • Included an assertion to verify that the NotSync field's value remains consistent after Marshal and Unmarshal operations.

Activity

• No human activity has occurred on this pull request yet.

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[gemini-code-assist]

Code Review

This pull request adds a test case to ensure that the NotSync field of DDLEvent correctly survives the Marshal/Unmarshal round-trip. This is a valuable addition to confirm the serialization behavior of this critical field, which controls DDL forwarding to downstream sinks. The changes are well-placed within the existing test structure and directly address the stated problem.

[wk989898]

I think we should use the json:"not_sync" instead of msg:"not_sync".

ticdc/pkg/common/event/ddl_event.go

Lines 34 to 108 in f1451ee

	type DDLEvent struct {
	// Version is the version of the DDLEvent struct.
	Version int `json:"version"`
	DispatcherID common.DispatcherID `json:"-"`
	// Type is the type of the DDL.
	Type byte `json:"type"`
	// SchemaID is from upstream job.SchemaID
	SchemaID int64 `json:"schema_id"`
	SchemaName string `json:"schema_name"`
	TableName string `json:"table_name"`
	// the following two fields are just used for RenameTable,
	// they are the old schema/table name of the table
	ExtraSchemaName string `json:"extra_schema_name"`
	ExtraTableName string `json:"extra_table_name"`
	Query string `json:"query"`
	TableInfo *common.TableInfo `json:"-"`
	StartTs uint64 `json:"start_ts"`
	FinishedTs uint64 `json:"finished_ts"`
	// The seq of the event. It is set by event service.
	Seq uint64 `json:"seq"`
	// The epoch of the event. It is set by event service.
	Epoch uint64 `json:"epoch"`
	// MultipleTableInfos holds information for multiple versions of a table.
	// The first entry always represents the current table information.
	MultipleTableInfos []*common.TableInfo `json:"-"`
	BlockedTables *InfluencedTables `json:"blocked_tables"`
	// BlockedTableNames is used by downstream adapters to get the names of tables that should block this DDL.
	// It is particularly used for querying the execution status of asynchronous DDLs (e.g., `ADD INDEX`)
	// that may be running on the table before this DDL.
	// This field will be set for most `InfluenceTypeNormal` DDLs, except for those creating new tables/schemas or dropping views.
	// It will be empty for other DDLs.
	// NOTE: For `RENAME TABLE` / `RENAME TABLES` DDLs, this will be set to the old table names.
	// For partition DDLs, this will be the parent table name.
	BlockedTableNames []SchemaTableName `json:"blocked_table_names"`
	NeedDroppedTables *InfluencedTables `json:"need_dropped_tables"`
	NeedAddedTables []Table `json:"need_added_tables"`
	// Only set when tables moves between databases
	UpdatedSchemas []SchemaIDChange `json:"updated_schemas"`
	// DDLs which may change table name:
	// Create Table
	// Create Tables
	// Drop Table
	// Rename Table
	// Rename Tables
	// Drop Schema
	// Recover Table
	TableNameChange *TableNameChange `json:"table_name_change"`
	TiDBOnly bool `json:"tidb_only"`
	BDRMode string `json:"bdr_mode"`
	Err string `json:"err"`
	// Call when event flush is completed
	PostTxnFlushed []func() `json:"-"`
	// eventSize is the size of the event in bytes. It is set when it's unmarshaled.
	eventSize int64 `json:"-"`
	// for simple protocol
	IsBootstrap bool `msg:"-"`
	// NotSync is used to indicate whether the event should be synced to downstream.
	// If it is true, sink should not sync this event to downstream.
	// It is used for some special DDL events that do not need to be synced,
	// but only need to be sent to dispatcher to update some metadata.
	// For example, if a `TRUNCATE TABLE` DDL is filtered by event filter,
	// we don't need to sync it to downstream, but the DML events of the new truncated table
	// should be sent to downstream.
	// So we should send the `TRUNCATE TABLE` DDL event to dispatcher,
	// to ensure the new truncated table can be handled correctly.
	// If the DDL involves multiple tables, this field is not effective.
	// The multiple table DDL event will be handled by filtering querys and table infos.
	NotSync bool `msg:"not_sync"`
	}

[wlwilliamx]

/test all