X-Git-Url: https://sipb.mit.edu/gitweb.cgi/ikiwiki.git/blobdiff_plain/4a1b921f6d1c91e62cecc9827ce3a15e1a2fff3e..70ce716007e2fdeabc3350a10ec08ff34c0246be:/doc/about_rcs_backends.mdwn diff --git a/doc/about_rcs_backends.mdwn b/doc/about_rcs_backends.mdwn index 476525e3c..0a95b7f54 100644 --- a/doc/about_rcs_backends.mdwn +++ b/doc/about_rcs_backends.mdwn @@ -1,16 +1,18 @@ -## A few bits about the RCS backends +A few bits about the RCS backends -### Terminology +[[toc ]] + +## Terminology ``web-edit'' means that a page is edited by using the web (CGI) interface as opposed to using a editor and the RCS interface. -### [[Subversion]] +## [[Subversion]] Subversion was the first RCS to be supported by ikiwiki. -#### How does it work internally? +### How does it work internally? Master repository M. @@ -28,12 +30,12 @@ see [[commit-internals]]. You browse and web-edit the wiki on W. -### [darcs](http://darcs.net/) (not yet included) +## [darcs](http://darcs.net/) (not yet included) Support for using darcs as a backend is being worked on by [Thomas Schwinge](mailto:tschwinge@gnu.org). -#### How will it work internally? +### How will it work internally? ``Master'' repository R1. @@ -59,7 +61,7 @@ separated parts in ikiwiki. What repository should [[RecentChanges]] and [[History]] work on? R1? -##### Rationale for doing it differently than in the Subversion case +#### Rationale for doing it differently than in the Subversion case darcs is a distributed RCS, which means that every checkout of a repository is equal to the repository it was checked-out from. There is @@ -75,10 +77,34 @@ off from R1. (To be continued.) +#### Another possible approach + +Here's what I (tuomov) think, would be a “cleaner” approach: + + 1. Upon starting to edit, Ikiwiki gets a copy of the page, and `darcs changes --context`. + This context _and_ the present version of the page are stored in as the “version” of the + page in a hidden control of the HTML. + Thus the HTML includes all that is needed to generate a patch wrt. to the state of the + repository at the time the edit was started. This is of course all that darcs needs. + 2. Once the user is done with editing, _Ikiwiki generates a patch bundle_ for darcs. + This should be easy with existing `Text::Diff` or somesuch modules, as the Web edits + only concern single files. The reason why the old version of the page is stored in + the HTML (possibly compressed) is that the diff can be generated. + 3. Now this patch bundle is applied with `darcs apply`, or sent by email for moderation… + there are many possibilities. -### [[Git]] (not yet included) +This approach avoids some of the problems of concurrent edits that the previous one may have, +although there may be conflicts, which may or may not propagate to the displayed web page. +(Unfortunately there is not an option to `darcs apply` to generate some sort of ‘confliction resolution +bundle’.) Also, only one repository is needed, as it is never directly modified +by Ikiwiki. -A patch with full [Git](http://git.or.cz) support is at . Regarding the patch, Recai says: +This approach might be applicable to other distributed VCSs as well, although they're not as oriented +towards transmitting changes with standalone patch bundles (often by email) as darcs is. + +## [[Git]] + +Regarding the Git support, Recai says: I have been testing it for the past few days and it seems satisfactory. I haven't observed any race condition regarding the concurrent blog commits @@ -91,34 +117,8 @@ part). GIT doesn't have a similar functionality like 'svn merge -rOLD:NEW FILE' (please see the relevant comment in mergepast for more details), so I had to invent an ugly hack just for the purpose. -Some other notes: - -- There are two separate helper packages in git.pm. To keep things self - confined, I haven't split it up. - -- I've used a (mini) Debug.pm during the tests and made it a separate file - for the convenience of others. It relies on the "constant folding" - feature of Perl, so there shouldn't be a runtime penalty (at least this - is what the 'perl -MO=Deparse shows', haven't made a real benchmark). - -- rcs_notify() has not been implemented yet (I have noticed it after I - finished the main work). - -- GIT backend uses the gitweb for repository browsing (the counterpart of - ViewCVS). - -- There might be some subs in GIT name space which you may prefer to move to - the main code. - -- Due to the reasons explained in the code, I've written an rcs_invoke() - wrapper. May be there should be a better approach to reach the same - goal. - -- There are some parts which I may change in future, like using a global - rcs_fatal_error and the ugly error reporting code in _rcs_commit. +## [mercurial](http://www.selenic.com/mercurial/) -- Documentation is missing. +Being worked on by Emanuele Aina. -It works for me, but of course in the end, the final decision is yours (due -to mostly GIT quirks, the implementation is not clean as SVN). Feel free -to fix/delete/add whatever you want. Hope it doesn't have any serious bug. \ No newline at end of file +