Talk:Summer of Code/2009/Print Support
Looks pretty good. A couple of quick questions, while it is still unfinished:
- Why do you do the PDF conversion on the server? Shouldn't the student be able to see a WYSIWYG version, margins and all?
- Is there a way for a student to cancel a request?
- At the moment, Sugar opens files by mime type, and each activity handles its own mime type(s). If you save a pdf to journal to be opened by the "send to server" activity, it would actually be opened by Read. Would you plan to modify sugar to have an "open with" metadata to cue it to open with your print activity? Or would you find some other workaround?
Homunq 03:01, 24 March 2009 (UTC)
Thing is we don't technically do a pdf conversion, CUPS comes with an emulator of the print engine, and prints to the PDF (cups-pdf modules to be specific to create a virtual printer). And we do this because we would like for the teacher to review it. The pdf is stored in a web folder on the server, and through moodle the teacher goes through them (we provide a webpage), and approves the ones he thinks appropriate for printing. I explained it my explanation The outcome of my second draft (beta) was that students should be provided as minimal functionality as possible. They shouldn't be given too much flexibility or options. And... you get WYSIWYG only as we send the files directly from the journal.
Yep, student can cancel his request, I forgot adding it. With The function cupsCancelJob() the student can cancel the job before his request goes to server (or before it can be printed to pdf). But after actually entering the web folder, It would become a bit complex. I would have to do this: 1) we would send in a query with the name of the file and a .pdf extension 2) if that file exists on web folder delete, otherwise do nothing 3) send suitable message back
No, no. There is ABSOLUTELY no need to interact with sugar activities, in the cups folder we have a file with the list of mime types accepted. We would also append the server supported CUPS Mimes to the clients CUPS. IF the mime type exists in cups mime.type , we are all good to do printing from journal. (that is why we require step 1) There is no reason to read the file, the server handles the necessary post script conversions!
Why the distinction?
To me, "mark for printing" and "save as PDF" should be one single option, as both should result in a PDF in the journal. "unmark for printing" would be something you did on that pdf, not on the original file. Homunq 00:25, 31 March 2009 (UTC)
Answer
I edited my proposal a lot so its more understandable now.
But my idea is use the same code, and when mark as printing is done, the pdf generated will not be shown to the user. It will be hidden and after sending it to the moodle queue, it will be deleted.And till that happenes only he can unmark for printing, Which will destroy the job before it reaches moodle's datastore.
After this he's free to again mark for printing. :D
And since only Write (abiword) can generate pdfs atm, we wont be able to generate pdfs for .py, or image types from other applications. A global pdf generation button would be awesome. And Unique!
And the reason I do conversion for case one is, a scenario where sugar recognized format might not be recognized by the teacher's machine.