br: fix debug decode backupmeta (#56627)

[ti-chi-bot]

This is an automated cherry-pick of #56627

What problem does this PR solve?

Issue Number: close #56296

Problem Summary:
We can only see the main backupmeta.json.

What changed and how does it work?

decode the meta file and stats file.

Check List

Tests

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

$ ls -aF1 /tmp/testbr
./
../
1/
backup.lock
backupmeta
backupmeta.datafile.000000001
backupmeta.schema.000000002
backupmeta.schema.stats.000000110
jsons/

$ ls -aF1 /tmp/testbr/jsons
./
../
backupmeta.datafile.000000001.json
backupmeta.json
backupmeta.schema.000000002.json
backupmeta.schema.stats.000000110.json

backupmeta.datafile.000000001.json

{
  "data_files": [
    {
      "name":"..",
      "sha256":"lu4KiCseT0M6dG2gghZXDwD5WOUOqDMhYKcLHMuDYGA=",
      "start_key":"..",
      "end_key":"..",
      "end_version":452625823236882437,
      "crc64xor":17088955387164552884,
      "total_kvs":1,
      "total_bytes":47,
      "cf":"write",
      "size":1673,
      "cipher_iv":..,
    },
    ...
  ],
}

backupmeta.schema.000000002.json

{
  "schemas":[
    {
      "db": ..,
      "table": ..,
      "crc64xor":4505190652257934775,
      "total_kvs":32,
      "total_bytes":3031,
    },
    ...
  ],
}

backupmeta.schema.stats.000000110.json

{
  "blocks":[
    {
      "physical_id":110,
      "json_table": ..,
    },
}

• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[codecov]

Codecov Report

Attention: Patch coverage is 46.08696% with 62 lines in your changes missing coverage. Please review.

Please upload report for BASE (release-7.5@e62cfd5). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-7.5     #57891   +/-   ##
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  Coverage               ?   72.1689%           
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  Files                  ?       1416           
  Lines                  ?     413247           
  Branches               ?          0           
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  Hits                   ?     298236           
  Misses                 ?      95021           
  Partials               ?      19990           

Flag	Coverage Δ
unit	72.1689% <46.0869%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.9400% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	53.5253% <0.0000%> (?)

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: 3pointer, Leavrth

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Needs approval from an approver in each of these files:

• br/OWNERS [3pointer,Leavrth]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-12-12 04:57:47.78457429 +0000 UTC m=+500857.873376834: ☑️ agreed by Leavrth.
• 2024-12-12 05:06:56.258256969 +0000 UTC m=+501406.347059507: ☑️ agreed by 3pointer.