On May 8, 2:49 pm, "Diez B. Roggisch" <de...@nospam.web.de> wrote: > koranthala wrote: > > Hi, > > I am doing web development using Django. I need to create an image > > (chart) and show it to the users - based on some data which user > > selects. > > My question is - how do I create a temporary image for the user? I > > thought of tempfile, but I think it will be deleted once the process > > is done - which would happen by the time user starts seeing the image. > > What makes you think that? You are the one creating it, you are responsible > for deleting it. > > > I can think of no other option other than to have another script which > > will delete all images based on time of creation. > > Since python is extensively used for web development, I guess this > > should be an usual scenario for many people here. How do you usually > > handle this? > > There are various solutions - tempfiles, files based on a criteria (e.g. > username and image-properties) so that they don't pollute the harddrive. > > For both approaches cleaning up as you suggest might be needed. > > Alternatively, if you use sessions, you can use memory-cached images. > > Or you can use the database. > > But the cleaning-up might get necessary here as well. > > The cleanest solution would be if the image would be rendered on the fly, > based on GET-parameters (or REST-ful urls) so that you can render it into > memory as string, but then forget immediately about it. > > Diez
Thank you Diez. I would like to go ahead with the cleanest solution indeed. I am creating the image on the fly. But I could not understand what you meant by render to memory as a string. How do we send the image to the browser? Were you mentioning about having the image as a string and then passing to the browser based on data URL scheme <RFC 2397> ? Or is it something else like XBM format or something? I am sorry - but I am quite unsure of what you meant? I am actually creating PDFs, CSVs and images on the fly. So, I need to delete them all after that. The images can be somewhat large - ~2MB. The RFC mentions that large data cannot be sent that way. Is it that I will have to delete the images using a separate script later? -- http://mail.python.org/mailman/listinfo/python-list
