Maybe the content is not properly stored in the JSON on github' side? But you
can use base64 in `accept:` to make it work.
json := STONJSON fromString: (ZnClient new
url: 'https://api.github.com/gists/5503544';
accept: 'application/vnd.github.v3.base64+json';
get).
b64 := ((json at: 'files') at: 'thumbnail.png') at: 'content'.
PNGReadWriter formFromStream: (Base64MimeConverter mimeDecodeToBytes: content
readStream).
Peter
On Wed, Apr 26, 2017 at 04:50:04PM +0200, Sven Van Caekenberghe wrote:
> I am puzzled by how they actually encoded the PNG as a String, I tried a
> couple of alternatives but I could not get binary data out of it so that it
> parsed successfully as PNG.
>
> If I would have to encode binary data in JSON I would use Base64 encoding
> (but alternatives exist).
>
> > On 24 Apr 2017, at 20:36, Juraj Kubelka <juraj.kube...@icloud.com> wrote:
> >
> > Hi,
> >
> > I was playing with GitHub Gist API and I have queried the following Gist:
> > https://gist.github.com/mbostock/5503544
> > I was interested how the PNG image is returned:
> > https://gist.github.com/mbostock/5503544#file-thumbnail-png
> >
> > I can obtain the whole Gist executing:
> >
> > STONJSON fromString:
> > (ZnClient new
> > url: 'https://api.github.com/gists/5503544';
> > accept: 'application/vnd.github.v3+json';
> > get).
> >
> > I can get PNG contents executing:
> >
> > pngData := (ZnEasy get:
> > ((((STONJSON fromString:
> > (ZnClient new
> > url: 'https://api.github.com/gists/5503544';
> > accept: 'application/vnd.github.v3+json';
> > get)) at: 'files') at: 'thumbnail.png') at: 'raw_url'))
> > contents.
> > PNGReadWriter formFromStream: rawPng readStream.
> >
> > But the PNG image is part of the Gist query and can be retrieved by:
> >
> > pngContent := ((((STONJSON fromString:
> > (ZnClient new
> > url: 'https://api.github.com/gists/5503544';
> > accept: 'application/vnd.github.v3+json';
> > get)) at: 'files') at: 'thumbnail.png') at: 'content').
> >
> > "As pngContent is a WideString, I cannot use:"
> > PNGReadWriter formFromStream: pngContent readStream.
> >
> > How can I read the PNG image from the pngContent? Any idea?
> > And the reverse question: How can I send the PNG bytes using JSON format?
> >
> > Thanks!
> > Juraj
> >
>
>
