Re: [media-types] I-D Action: draft-ietf-mediaman-suffixes-00.txt

["Martin J. Dürst" <[e-mail]>]

Hello Chris,

Glad to see you here.

On 2022-02-18 05:28, Chris Lilley wrote:
> 
> On 2022-02-17 14:44, Manu Sporny wrote:
>> image/svg+xml - as long as some preliminary application can gunzip the 
>> data, a
>> secondary application that understands image/svg+xml can process it
> 
> This is the part that requires precision, with regard to right-to-left 
> unpacking of suffixes.
> 
> There have been issues in the past (especially in non-HTTP contexts, 
> such as file:// or data://) with an application receiving a gzipped SVG 
> (.svgz) file and then simply saying "this is not a well formed XML 
> document" because the preliminary application part was unspecified.

Yes, I can imagine that. I checked out the SVG spec yesterday, because I 
was quite sure that it would contain detailed instructions about media 
types. In SVG 1.1, I found 
(https://www.w3.org/TR/SVG11/intro.html#MIMEType):

 >>>>
The MIME type for SVG is "image/svg+xml" (see XML Media Types 
[RFC3023]). The registration of this MIME type is in progress at the W3C.

It is recommended that SVG files have the extension ".svg" (all 
lowercase) on all platforms. It is recommended that gzip-compressed 
[RFC1952] SVG files have the extension ".svgz" (all lowercase) on all 
platforms.
 >>>>

In SVG 2.0 (Editor's Draft), I found 
(https://www.w3.org/TR/SVG2/conform.html#ConformingSVGServers):

 >>>>
Also, if the SVG file is compressed with gzip or deflate, conforming SVG 
Servers must indicate this with the appropriate header, according to 
what the protocol supports. Specifically, for content compressed by the 
server immediately prior to transfer, the server must use the 
"Transfer-Encoding: gzip" or "Transfer-Encoding: deflate" headers as 
appropriate, and for content stored in a compressed format on the server 
(e.g. with the file extension "svgz"), the server must use the 
"Content-Encoding: gzip" or "Content-Encoding: deflate" headers as 
appropriate.
 >>>>

This is correct in terms of HTTP,..., but it doesn't take into account 
Russ's case, which I understand is labeling a blob of gzipped SVG just 
with a MIME media type.

Regards,   Martin.