[KAFKA-10685] --to-datetime passed to kafka-consumer-groups interpreting microseconds wrong

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.7.0
• Fix Version/s: 2.8.0
• Assignee: Luke Chen
• Reporter: Russell Sayers
• Created: 05/Nov/20 05:51
• Updated: 17/Nov/20 19:33
• Resolved: 17/Nov/20 19:32

Description

If you pass more than 3 decimal places for the fractional seconds of the datetime, the microseconds get interpreted as milliseconds.

kafka-consumer-groups --bootstrap-server kafka:9092 
--reset-offsets 
--group webserver-avro 
--topic driver-positions-avro 
{{ --to-datetime "2020-11-05T00:46:48.002237400" }}
{{ --dry-run}}

Relevant code here. The datetime is being turned into Nov 5, 2020 1:24:05.400 because SimpleDateFormat is adding 2237400 milliseconds to Nov 5, 2020 00:46:48.

Experimenting with getDateTime:

• getDateTime("2020-11-05T00:46:48.000") -> 1604537208000
• getDateTime("2020-11-05T00:46:48.000+0800") -> 1604508408000 - correct the formatting string allows for ZZZ timezones
• getDateTime("2020-11-05T00:46:48.000123") -> 1604537208123 - note this ends with 123 milliseconds.

The pattern string is "yyyy-MM-dd'T'HH:mm:ss.SSS".  So SimpleDateFormat interprets "000123" as 123 milliseconds. See the stackoverflow answer here.

The fix?  Remove any digits after more than 3 characters after the decimal point, or raise an exception. The code would still need to allow the RFC822 timezone, i.e Sign TwoDigitHours Minutes.

 

Issue Links

• links to: GitHub Pull Request #9576