SAMP and HTTPS workaround?

[Mark Taylor]

Hi Doug,

thanks for registering an interest.  Any input on the topic welcome.
I guess the question I'd put related to the approach I'm suggesting
here is, how easy/hard would you expect it to be to encourage
WWT/CSC users to download and configure or use a helper application
along these lines?

My only other comment at this stage is it shouldn't make any difference
whether the URL points at a fixed file or represents a dynamic query.

Mark

On Thu, 22 Aug 2019, Burke, Douglas wrote:

> Mark,
> 
> I've been using your WebSAMP JS library [1] with our WWT interface to the
> Chandra Source Catalog - http://cxc.harvard.edu/csc2/wwt.html - to send
> URLs that return a votable or fits file when retrieved (ie the URL is
> actually a query and not to a file [2]). We are moving to https "soon" so I
> am interested in any possible solution (once the WWT client is moved over
> to https, that is).
> 
> Ta,
> Doug
> 
> [1] so thanks for that
> [2] thanks to a confluence of influences that aren't relevant here
> 
> 
> On Thu, Aug 22, 2019 at 9:05 AM Mark Taylor <M.B.Taylor at bristol.ac.uk>
> wrote:
> 
> > Dear SAMP users,
> >
> > the problem of Web SAMP and HTTPS has been under discussion
> > for a while now - basically the Web Profile works fine with HTTP
> > but won't work from pages served using HTTPS.  A possible HTTPS-capable
> > profile has been prototyped, but it's pretty nasty.  There is much
> > more information on the topic here:
> >
> >    http://andromeda.star.bristol.ac.uk/websamp/
> >
> > As an alternative to the HTTPS profile, I'm thinking about more
> > lightweight workarounds.  One is just to provide a simple helper
> > application that takes a suitable filename on the command line
> > (VOTable table or FITS image) and sends it to a running SAMP
> > client.  Such an application could be associated in the
> > browser with suitable MIME types (application/x-votable+xml,
> > image/fits), or you could just choose it when the browser
> > asks you what application you want to open a downloaded file with.
> >
> > This is much less flexible than allowing the web page (web application)
> > to interact with the SAMP hub itself, which is what you can do
> > with SAMP+Web Profile.  However, in practice, nearly(?) all Web SAMP
> > pages that I'm aware of just use Web SAMP to allow the user to
> > send a samp.load.votable or image.load.fits message, and that's
> > done nearly as well by the helper application.  It works with
> > rather than against normal browser operations, which makes it
> > much less painful to implement than the HTTPS profile;
> > it works equally with HTTPS or HTTP, and no additional
> > infrastructure is required.  The main downside is that the user has
> > to configure it somehow (install script, tell browser to use it
> > to handle relevant files).
> >
> > I have written such a helper application, and I'd be interested
> > to know if anyone wants to try it out: especially data providers
> > who are using HTTPS and want to allow users to load tables/images
> > using SAMP.  Would this be an acceptable solution?
> >
> > You can find the application here:
> >
> >    http://andromeda.star.bris.ac.uk/websamp/sampload.jar
> >
> > If you run, e.g. "java -jar sampload.jar /tmp/tmpfile.vot"
> > then it will pop up a window asking which VOTable-capable
> > SAMP client you want to send tmpfile.vot to.
> > (It works out what kind of file it is by looking at the content).
> >
> > Unless your OS/browser can execute jar files directly, to use it with
> > a browser you'll need to accompany it with a small shell script or
> > equivalent like
> >
> >    #!/bin/sh
> >    java -jar /path/to/sampload.jar "$@"
> >
> > Any feedback, comments, ideas welcome.
> >
> > Mark
> >
> > --
> > Mark Taylor   Astronomical Programmer   Physics, Bristol University, UK
> > m.b.taylor at bris.ac.uk +44-117-9288776  http://www.star.bris.ac.uk/~mbt/
> >
> 

--
Mark Taylor   Astronomical Programmer   Physics, Bristol University, UK
m.b.taylor at bris.ac.uk +44-117-9288776  http://www.star.bris.ac.uk/~mbt/