pkg/tz(ticdc): use correct ctx to get timezone

[Rustin170506]

What problem does this PR solve?

Issue Number: ref #8798

What is changed and how it works?

• Fix a bug that unescape the timezone value twice
• Fix a bug we use the wrong ctx when we get the timezone.
• Warning when users use time-zone="" in sink-uri.
• Warning when users do not set the timezone in sink-uri

Check List

Tests

• Unit test
• Manual test (add detailed scripts or steps below)
  • pkg/tz(ticdc): use correct ctx to get timezone #8799 (comment)
  • pkg/tz(ticdc): use correct ctx to get timezone #8799 (comment)

Questions

Will it cause performance regression or break compatibility?

None

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

None

Release note

Fix the bug that TiCDC always uses `UTC` when creating changefeed

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• amyangfei
• nongfushanquan

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[Rustin170506]

Test it locally to make sure we use the correct timezone from the ctx.

1. install the MySQL with homebrew, it would use the system timezone as MySQL timezone
2. start upstream tidb cluster, build and ticdc with this PR
3. start ticdc server without timezone config(it would use system)
4. try to create changefeed, it would use the Asia/Shanghai instead of UTC.

➜  bin git:(rustin-patch-timezone) ✗ ./cdc cli changefeed create --sink-uri="mysql://root:123456@127.0.0.1:3306" -c "test1"
Error: [CDC:ErrMySQLConnectionError]fail to open MySQL connection: Error 1298 (HY000): Unknown or incorrect time zone: 'Asia/Shanghai'

[Rustin170506]

Test it locally to make sure it will bail out when the changefeed timezone is different from server.

1. install the MySQL with homebrew, it would use the system timezone as MySQL timezone
2. start upstream tidb cluster, build and ticdc with this PR
3. start ticdc server without timezone config(it would use system)
4. try to create changefeed, it would bail out an error.

➜  bin git:(rustin-patch-timezone) ./cdc cli changefeed create --sink-uri="mysql://root:123456@127.0.0.1:3306?time-zone=UTC" -c "test3"
Error: [CDC:ErrMySQLInvalidConfig]MySQL config invalid: the timezone of the TiCDC server and the sink-uri are inconsistent. TiCDC server timezone: Asia/Shanghai, sink-uri timezone: UTC. Please make sure that the timezone of the TiCDC server, sink-uri and the downstream database are consistent.

[Rustin170506]

/test all

[amyangfei]

/merge

[ti-chi-bot]

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

Commit hash: 671c134

[Rustin170506]

/retest

[Rustin170506]

/test all

[Rustin170506]

/test all

[ti-chi-bot]

@hi-rustin: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

trigger some heavy tests which will not run always when PR updated.

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[Rustin170506]

/retest

[Rustin170506]

/retest

[Rustin170506]

/test cdc-integration-mysql-test /tiflash=release-6.6 /tikv=release-6.6

[Rustin170506]

/retest

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #8830.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #8831.