Fix error and success handling on image pull

[marusak]

We have shown error on every pull because we tried to parse the whole
response as one JSON, but in fact it is a group of JSONs. That meant we
failed to notice the fact that we were not showing any useful error when
downloading actually failed. (We always just shown that we could not
parse the response)

Fixes #640

[marusak]

I suspect that we will need naughty for containers/podman#8870 but lets see first what our bots think.

[KKoukiou]

Hmm the API is weird here or is it me? libpod pull should fail properly when the pull fails and we should catch it in catch without searching for error in the successful response.

Your changes make the error show up, so we should merge them, but should we report a bug in podman for the API?

In addition, when in non-existent tag is used when downaloading an image, the API fail with a not-so-good error message.

:note the screenshot is with your change included.

[marusak]

Hmm the API is weird here or is it me? libpod pull should fail properly when the pull fails and we should catch it in catch without searching for error in the successful response.

Yeah, kinda what I expected as well. But it is streaming so it does not have chance to response with different error code.

In addition, when in non-existent tag is used when downaloading an image, the API fail with a not-so-good error message.

this is bug in podman, reported as containers/podman#8870