Consider this :)(error message, ignore the choice of bytes) 

$ perl -MEncode -MJSON -e " print JSON->new->utf8(0)->pretty(1)->encod
+e([ decode 'utf8', qq{\xFA\xFG} ]); "
Wide character in print at -e line 1.
[
   "�\u000fG"
]

$ perl -MEncode -MJSON -e " print JSON->new->ascii(1)->pretty(1)->enco
+de([ decode 'utf8', qq{\xFA\xFG} ]); "
[
   "\ufffd\u000fG"
]

[download]

The error Body must be bytes and should not contain wide characters (UTF-8 strings) comes from Plack::Middleware::Lint, and I remember a similar message from LWP/HTTP::Message. I've learned from perlunitut: Unicode in Perl#I/O flow (the actual 5 minute tutorial) that this means you have to write 

return encode 'UTF-8', JSON->...

[download]

I write JSON because JSON loads JSON::XS if its available, but the code doesn't break of JSON::XS isn't available for some reason :)

This is confirmed by PSGI::FAQ#I want to send Unicode content in the HTTP response. How can I do so?

I'm wouldn't be surprised if there exists a Plack::Middleware::Encoding or some such which automatically encodes your UTF-8 strings and adds a charset header, but I haven't seen one

In reply to Re: utf8/yui/json/ajax/plack troubles by Anonymous Monk
in thread utf8/yui/json/ajax/plack troubles by ron.savage

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