streamer: fix duplicate event when reparse relay using GTID

[lance6716]

What problem does this PR solve?

part of #1524

What is changed and how it works?

when DM uses GTID and needs to return a reparse location, return last XID location so that replaceWithHeartbeat will be correctly calculated

Check List

Tests

• Unit test

Code changes

Side effects

Related changes

• Need to cherry-pick to the release branch

[lance6716]

/cc @GMHDBJD @lichunzhu

[lance6716]

/run-all-tests

[lance6716]

/run-compatibility-test

[lance6716]

/auto-cc

[GMHDBJD]

Will sync unit get duplicate events? (like gtid_event, table map event, rows event)

[lance6716]

Will sync unit get duplicate events? (like gtid_event, table map event, rows event)

Yes, currently we rely on safe mode. I added a todo of changing the behaviour of sending binlog to "sending DML after see XID". Do you think we should do it now?

[GMHDBJD]

Yes, currently we rely on safe mode. I added a todo of changing the behaviour of sending binlog to "sending DML after see XID". Do you think we should do it now?

I think we may simply return both currentGTID and latestPos for parseFile or save latest gtid now. Otherwise, if safemode has been closed, we may have duplicate data. Or if sending DML after see XID is easy, that's ok.

[GMHDBJD]

/lgtm

[ti-chi-bot]

[REVIEW NOTIFICATION]

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• GMHDBJD
• lichunzhu

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[lance6716]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 3ed9b0a

[ti-srebot]

cherry pick to release-2.0 in PR #1532