Re: [xwiki-devs] [Proposal] URL format for temporary resources

On 15 Apr 2016, at 11:00, Eduard Moraru &lt;enygma2002(a)gmail.com&gt; wrote: Hi, Re http://<server>/<context>/tmp/<module id>/<serialized owner document reference>/<module-dependent resource path> 1. What determines this <module id>? What about collisions between extensions not knowing about eachother?

2. Are all these temporary resources bound to a document? What about the ones that are not? They would use some random doc reference there? Would that matter?

As far as I see it, after http://<server>/<context>/tmp/<module id>/ we can have pretty much anything (i.e. <module-dependent resource path>), depending on the app's needs. Alternatively, this being a generic service, maybe we can assign a random ID on request and keep a mapping in a separate table.

We could even drop the <module id> from the URL and store it in the table instead (as a column). The idea would be that we would not need to expose all these "coordinates" in the actual URL and pollute it with the logic of each individual module, but only use a generic random (unique) ID since it`s a temporary resource anyway. Also, being a separate DB table, the data will not be available on an export since it`s temporary anyway. What is left, IMO, is a way to clean this temporary data. On the DB table side, we can always clean the table data on startup and the URLs will be gone, however we would need a way to also actually delete the corresponding temporary files and that may be dependant on the module`s logic. Anyway, WDYT about this direction so far, with using simply http://<server>/<context>/tmp/<resource id>?

Thanks, Eduard On Fri, Apr 15, 2016 at 11:30 AM, Marius Dumitru Florea < mariusdumitru.florea(a)xwiki.com&gt; wrote: > On Thu, Apr 14, 2016 at 7:46 PM, Vincent Massol &lt;vincent(a)massol.net&gt; > wrote: > >> >>> On 14 Apr 2016, at 16:52, Marius Dumitru Florea < >> mariusdumitru.florea(a)xwiki.com&gt; wrote: >>> >>> On Thu, Apr 14, 2016 at 5:43 PM, Vincent Massol &lt;vincent(a)massol.net&gt; >> wrote: >>> >>>> Hi devs, >>>> >>>> I’m implementing http://jira.xwiki.org/browse/XWIKI-10375 ("Refactor >> the >>>> temporary resource concept inside the Resource module”) and I need to >>>> define a URL format for the new “tmp” resource type. >>>> >>>> I’m proposing the following: >>>> >>>> >>> >>>> http://<server>/<context>/tmp/<module id>/<serialized owner document >>>> reference>/<module-dependent resource path> >>>> >>> >>> Serialized document reference uses backslash to escape special > characters >>> which breaks the URL in Tomcat for security reasons. >> >> > >> Yes but the same is true whether you have “A\.B.C” or "/A\.B/C”. >> > > WDYM? The dot is escaped in the space name with a backslash only when the > space name is serialized as a reference, which is not the case for the > standard wiki page URL /xwiki/bin/view/Space.With.Dot/Page.With.Dot > > Having a slash or a backslash in the space or page name is less common than > having a dot ("Version 1.2"). And the user might be willing to accept that > having a backslash in the page (or attachment's) name can cause security > issues with Tomcat, but I doubt he will accept to avoid dots. > > >> That’s not a blocking issue anyway since we can easily transform them > into >> other characters when we serialized and do the opposite when we parse the >> URL. >> >>> This is based on the existing TemporaryResourceReference at: >>>> >>>> >> > https://github.com/xwiki/xwiki-platform/blob/96caad053c14fc5546e9bc141bc284… >>>> >>>> For example: >>>> >>>> http:// >>>> >> > <server>/<context>/tmp/officeviewer/A.B.WebHome/Q29tcGFueSBQcmVzZW50YXRpb24ucHB0/Company+Presentation-slide0.jpg >>>> >>>> Note that in this example from the officeviewer macro the >> module-dependent >>>> resource path consists in: >>>> >>> >>> >>>> - base64(name of office attachment + hashcode(parameters)) >>>> >>> >>> See http://jira.xwiki.org/browse/XWIKI-11528 for the rationale behind >> it. I >>> was trying to avoid backslash (from the serialized attachment > reference) >> in >>> the URL. >> >> > >> Yes. However the image name “Company Presentation-slide0” could also >> contain slash or backlashes too. >> > > It could but it's less common, especially because most Operating Systems > are not very friendly with these characters when used in file or folder > names. > > >> >> Note that I wasn’t sure why you you didn’t compute the base64 of both the >> name of attachment + the parameters instead of having 2 directory levels >> consisting in the base64 of the attachment name + the hashcode of the >> parameters as different path segments. Need to check XWIKI-11528, maybe >> it’s there. >> >> IMO we need to treat all path segments in the same way and convert slash >> and backslash into some other characters. I’m not sure we need the base64 >> solution. But anyway this is an implementation detail of the officeviewer >> module and not really related to the discussion of the generic Temporary >> URL format. >> >> Thanks >> -Vincent >> >>> - generated image name from PPT >>>> >>>> In this case, the implementation would generate the following file: >>>> >>>> >>>> >> > [TMPDIR]/officeviewer/A/B/WebHome/Q29tcGFueSBQcmVzZW50YXRpb24ucHB0/Company+Presentation-slide0.jpg >>>> >>>> WDYT? >>>> >>>> Thanks >>>> -Vincent