parsing ISO 8601 dates

[Dennis Schmidt]

Following http://stackoverflow.com/questions/2201216/is-there-a-simple-way-of-converting-an-iso8601-timestamp-to-a-formatted-nsdate
there is no direct (that is, just by passing a format string) way to
parse an ISO 8601 date string like "2011-07-13T04:58:56-07:00". The
colon in the time offset seems to be the problem.

Rails (3) JSON output by default returns date strings in that format
though and I would like to parse them using RestKit.

[objectMapping.dateFormatStrings addObject:@"yyyy-MM-
dd'T'hh:mm:ssZZ"];

doesn't work for me, tested with Z, ZZ or ZZZ at the end.
So is there any way to parse that string or would I have to change my
default rails JSON output?

[Rob Booth]

I've run into this in the past, before using RestKit, but I just
tested the format string I was using in the past and this works:
[mapping.dateFormatStrings addObject:@"yyyy-MM-dd HH:mm:ss'Z'"]; The
issue I'm running into with dates is that I need to include the
timezone of the dateformatter.

NSDateFormatter* dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss'Z'"];
[mapping.dateFormatters addObject:dateFormatter];

Rob

I'd love to be able to just give RestKit an array of date formatters
for it to use instead of an array of strings.

[Dennis Schmidt]

Hey Rob, thanks for the reply. Unfortunately

[mapping.dateFormatStrings addObject:@"yyyy-MM-dd HH:mm:ss'Z'"];

doesn't work for me, neither...

On 13 Jul., 18:41, Rob Booth <rob.o.bo...@gmail.com> wrote:
> I've run into this in the past, before using RestKit, but I just
> tested the format string I was using in the past and this works:
> [mapping.dateFormatStrings addObject:@"yyyy-MM-dd HH:mm:ss'Z'"];  The
> issue I'm running into with dates is that I need to include the
> timezone of the dateformatter.
>
> NSDateFormatter* dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
> [dateFormatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
> [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss'Z'"];
> [mapping.dateFormatters addObject:dateFormatter];
>
> Rob
>
> I'd love to be able to just give RestKit an array of date formatters
> for it to use instead of an array of strings.
>
> On Wed, Jul 13, 2011 at 8:16 AM, Dennis Schmidt
>
>
>
>
>
>
>

> <metzelti...@googlemail.com> wrote:
> > Followinghttp://stackoverflow.com/questions/2201216/is-there-a-simple-way-of-c...

[Victor Kryukov]

The problem is indeed with NSDateFormatter - it parses everything according to http://unicode.org/reports/tr35/tr35-10.html#Date_Format_Patterns, so Z at the end means 'parse timezone according to RFC 822' which doesn't allow for colons.

The following quick patch (warning: not tested!) will extend RestKit to allow not just NSStrings (which will be feed to NSDateFormatter's setDateFormat:) but also _any_ object that responds to @selector(dateFromString:) as date formatters.

https://github.com/victorkryukov/RestKit/commit/15a44fd2688e1019b07291943198719bb79dce45

So you should be able to just add your own parser, and everything should work.

@class MyISO8601DateFormatter; // implements dateFromString: to parse ISO 8601 dates

[mapping.dateFormatStrings addObject:[[[MyISO8601DateFormatter] alloc] init] autorelease]];

[Blake Watters]

We have been moved to an array of date formatters on the GateGuru fork as a performance optimization. If someone wants to extract it or send a pull request to improve the situation on this, I'll merge it.

[Kyle Clegg]

Is there still a working github link out there?  I'm in need of a fix for this same problem.

[Kyle Clegg]

Decent documentation on this now exists here: https://github.com/RestKit/RestKit/wiki/Configuring-Date-and-Time-Mapping