Support iso offset date time format via special value for spring.mvc.format.date-time

[manderson23]

I have to use DateTimeFormatter.ISO_OFFSET_DATE_TIME in Spring MVC controllers with OffsetDateTime parameters.

It would be useful if the new spring.mvc.format.date-time property could accept a value iso-offset as a shortcut for this.

[philwebb]

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Problem

The spring.mvc.format.date-time property has a convenient shortcut that can be used for ISO formatted dates. In addition to supporting the "iso" shortcut, we'd like to support "iso-offset" which would map to the ISO_OFFSET constants in java.time.format.DateTimeFormatter

Solution

The actual logic for this shortcut is in the org.springframework.boot.autoconfigure.web.format.DateTimeFormatters class. The method of that class call isIso to determine if the ISO format should be used and then return the appropriate formatter.

This logic should be updated so that iso-offset or isooffset can be used as a value.

Steps to Fix

• Claim this issue with a comment below and ask any clarifying questions you need
• Set up a repository locally following the Contributing Guidelines
• Try to fix the issue following the steps above
• Commit your changes and start a pull request.

[philwebb]

@gaurav-91 has been asking if he can help with issues, so I'd like to give him the opportunity to claim this one if they'd like to.

[gaurav-91]

Thank you @philwebb , I would love to start working on it. Apologies for commenting on multiple requests as this is first time I am starting up on open source.

[gaurav-91]

@philwebb Just make sure my understanding is correct we need to edit additional-spring-configuration-metadata.json with extra property for "spring.mvc.format.date-time" alone and then corresponding changes into public DateTimeFormatters dateTimeFormat(String pattern) method.

Or it is required to be added for dateFormmatter & timeFormatter as well.
Thanks

[philwebb]

I believe that three methods (dateFormat, timeFormat and dateTimeFormat) in DateTimeFormatters will all need to be updated and likewise all three of the properties in configuration-metadata.json.

Feel free to submit a pull-request with FIXMEs if you like and we can iterate on the code together next week.

[gaurav-91]

I have made the changes but was trying write sample test case as well for it. Below is what is tried but doesn't seem to be correct to me.

WebConversionService conversionService = new WebConversionService(new DateTimeFormatters().dateFormat("isooffset"));
//LocalDate date = LocalDate.parse("2011-12-03", DateTimeFormatter.ISO_OFFSET_DATE);
OffsetDateTime offsetdate=new Date().toInstant().atOffset(ZoneOffset.ofHoursMinutes(1, 30));
System.out.println(conversionService.convert(offsetdate, String.class));
assertThat(conversionService.convert(offsetdate, String.class))		.isEqualTo(DateTimeFormatter.ISO_OFFSET_DATE.format(offsetdate));

Could you please guide me little bit here.