id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
2	don't offer the option to save changes when you are viewing read-only	zooko	somebody	"If you view a tiddly wiki through a read-write capability, like this:

http://testgrid.allmydata.org:8123/uri/URI%3ADIR2%3Aedsdo6ees7ugabbyyy65635y5y%3Axthwymetpwjs5brmobmcjg7zeld37hdnc6jxyw5crayykraaufma/wimm.html

Then you should have a ""Save Changes"" button.  But if you are viewing it through a read-only capability, like this:

http://testgrid.allmydata.org:8123/uri/URI:DIR2-RO:kjtsjg4qrpzgjymiupf7qt2beu:xthwymetpwjs5brmobmcjg7zeld37hdnc6jxyw5crayykraaufma/wimm.html

Then you should not.

Note that those are two views on the same file, so for example if you edit and save the file using the read-write view, your changes will be visible in the read-only view.

Currently you get a ""Save Changes"" button in both cases, but if you try to use that button in the latter case then it fails.

One way to implement this feature -- the feature of showing the Save Changes button only in the case of the file being writable -- would be to parse the URL and see if it is a tahoe {{{/uri/URI:DIR2}}} URL or if it is a tahoe {{{/uri/URI:DIR2-RO}}} URL.  However, it would be too bad if adding this feature made the 
!HTTPSavingPlugin become Tahoe-specific, because currently the !HTTPSavingPlugin is entirely general -- any server which respects the simple REST notion that ""HTTP PUT to a URL ought to overwrite the resource located there"" will work with the current !HTTPSavingPlugin.

So one way to go about it that might be more general is to have the HTTPSavingPlugin do a test PUT when it loads.  If that PUT succeeds, then enable the ""Save Changes"" button.  If that PUT gets an error, then keep that button hidden.
"	defect	closed	major		component1		fixed