parser_json: Handle numeric timestamps

[hvenev]

The time_unit_per_second parser option enables parsing JSON numbers as timestamps. The same time_key is used as for time_format.

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Testing
Before we can approve your change; please submit the following in a comment:

• Example configuration file for the change

[PARSER]
	Name json
	Format json
	Time_Key timestamp
	Time_Unit_Per_Second 1

• Debug log output from testing the change

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• Attached Valgrind output that shows no leaks or memory corruption was found

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• Run local packaging test showing all targets (including any new ones) build.

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• Set ok-package-test label to test for all targets (requires maintainer to do).

Documentation

• Documentation required for this feature

TODO

Backporting

• Backport to latest stable release.

Probably not?

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[edsiper]

I would suggest to extend time_format and use a special value like SECONDS instead of adding a new config property

[hvenev]

I would suggest to extend time_format and use a special value like SECONDS instead of adding a new config property

Like this?

[edsiper]

@hvenev yes