X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/45d08022bbb97f1731951402997fa343f82c1494..cc5be82b8b7cfe3b679d8ba4f0d62e0894d9f964:/doc/plugins/po.mdwn diff --git a/doc/plugins/po.mdwn b/doc/plugins/po.mdwn index 326a6f39f..756012890 100644 --- a/doc/plugins/po.mdwn +++ b/doc/plugins/po.mdwn @@ -2,34 +2,51 @@ [[!tag type/format]] This plugin adds support for multi-lingual wikis, translated with -gettext, using [po4a|http://po4a.alioth.debian.org/]. +gettext, using [po4a](http://po4a.alioth.debian.org/). It depends on the Perl `Locale::Po4a::Po` library (`apt-get install po4a`). +As detailed bellow in the security section, `po4a` is subject to +denial-of-service attacks before version 0.35. + +[[!toc levels=2]] Introduction ============ -A language is decided to be the "master" one, and any other supported -language is a "slave" one. A page written in the "master" language is -a "master" page, and is written in any supported format but PO. +A language is chosen as the "master" one, and any other supported +language is a "slave" one. + +A page written in the "master" language is a "master" page. It can be +of any page type supported by ikiwiki, except `po`. It does not have to be +named a special way: migration to this plugin does not imply any page +renaming work. Example: `bla/page.mdwn` is a "master" Markdown page written in English; if `usedirs` is enabled, it is rendered as -`bla/page/index.html.en`, else as `bla/page.html.en`. +`bla/page/index.en.html`, else as `bla/page.en.html`. -Translations of a "master" page into a "slave" language are called -"slave" pages, and is a in gettext PO format. PO is thus promoted to -the wiki page type status. +Any translation of a "master" page into a "slave" language is called +a "slave" page; it is written in the gettext PO format. `po` is now +a page type supported by ikiwiki. Example: `bla/page.fr.po` is the PO "message catalog" used to translate `bla/page.mdwn` into French; if `usedirs` is enabled, it is -rendered as `bla/page/index.html.fr`, else as `bla/page.html.fr` +rendered as `bla/page/index.fr.html`, else as `bla/page.fr.html` + +(In)Compatibility +================= + +This plugin does not support the `indexpages` mode. If you don't know +what it is, you probably don't care. Configuration ============= -`po_master_language` is used to set the master language in +Supported languages +------------------- + +`po_master_language` is used to set the "master" language in `ikiwiki.setup`, such as: po_master_language => { 'code' => 'en', 'name' => 'English' } @@ -37,11 +54,57 @@ Configuration `po_slave_languages` is used to set the list of supported "slave" languages, such as: - po_slave_languages => { 'fr' => { 'name' => 'Français', }, - 'es' => { 'name' => 'Castellano', }, - 'de' => { 'name' => 'Deutsch', }, - }, + po_slave_languages => { 'fr' => 'Français', + 'es' => 'Castellano', + 'de' => 'Deutsch', + } + +Decide which pages are translatable +----------------------------------- + +The `po_translatable_pages` setting configures what pages are +translatable. It is a [[ikiwiki/PageSpec]], so you have lots of +control over what kind of pages are translatable. + +The `.po` files are not considered as being translatable, so you don't need to +worry about excluding them explicitly from this [[ikiwiki/PageSpec]]. + +Internal links +-------------- + +### Links targets +The `po_link_to` option in `ikiwiki.setup` is used to decide how +internal links should be generated, depending on web server features +and site-specific preferences. + +#### Default linking behavior + +If `po_link_to` is unset, or set to `default`, ikiwiki's default +linking behavior is preserved: `\[[destpage]]` links to the master +language's page. + +#### Link to current language + +If `po_link_to` is set to `current`, `\[[destpage]]` links to the +`destpage`'s version written in the current page's language, if +available, *i.e.*: + +* `foo/destpage/index.LL.html` if `usedirs` is enabled +* `foo/destpage.LL.html` if `usedirs` is disabled + +#### Link to negotiated language + +If `po_link_to` is set to `negotiated`, `\[[page]]` links to the +negotiated preferred language, *i.e.* `foo/page/`. + +(In)compatibility notes: + +* if `usedirs` is disabled, it does not make sense to set `po_link_to` + to `negotiated`; this option combination is neither implemented + nor allowed. +* if the web server does not support Content Negotiation, setting + `po_link_to` to `negotiated` will produce a unusable website. Server support ============== @@ -49,121 +112,205 @@ Server support Apache ------ -Using `mod_negotiation` makes it really easy to have Apache serve the -page in the client's preferred language, if available. This is the -default Debian Apache configuration. +Using Apache `mod_negotiation` makes it really easy to have Apache +serve any page in the client's preferred language, if available. +This is the default Debian Apache configuration. When `usedirs` is enabled, one has to set `DirectoryIndex index` for the wiki context. Setting `DefaultLanguage LL` (replace `LL` with your default MIME -language) for the wiki context can be needed, to ensure -`bla/page/index.html.en` is served as `Content-Language: LL`. -**FIXME**: is it still needed with the new `.html.en` naming convention? +language code) for the wiki context can help to ensure +`bla/page/index.en.html` is served as `Content-Language: LL`. lighttpd -------- lighttpd unfortunately does not support content negotiation. +**FIXME**: does `mod_magnet` provide the functionality needed to + emulate this? -TODO -==== -Display available translations ------------------------------- +Usage +===== -The [[linguas|plugins/contrib/linguas]] plugin has some code that can -be used as a basis to display the existing translations, and allow to -navigate between them. +Templates +--------- -View translation status ------------------------ +When `po_link_to` is not set to `negotiated`, one should replace some +occurrences of `BASEURL` with `HOMEPAGEURL` to get correct links to +the wiki homepage. -One should be able to view some freshness information about the -translation status, either for a given page or for the whole wiki. +The `ISTRANSLATION` and `ISTRANSLATABLE` variables can be used to +display things only on translatable or translation pages. -This should not be too hard using gettext tools. If this is -implemented as a -[[HTML::Template|http://search.cpan.org/search?mode=dist&query=HTML%3A%3ATemplate]] -loop, a page using it should depend on any "master" and "slave" pages -whose status is being displayed. +### Display page's versions in other languages -Decide which pages are translatable ------------------------------------ +The `OTHERLANGUAGES` loop provides ways to display other languages' +versions of the same page, and the translations' status. + +One typically adds the following code to `templates/page.tmpl`: + + +
+ +
+ + +The following variables are available inside the loop (for every page in): + +* `URL` - url to the page +* `CODE` - two-letters language code +* `LANGUAGE` - language name (as defined in `po_slave_languages`) +* `MASTER` - is true (1) if, and only if the page is a "master" page +* `PERCENT` - for "slave" pages, is set to the translation completeness, in percents -The subset of ("master") pages supporting translation must be -configurable: +### Display the current translation status -- a `[[!translatable ]]` directive, when put on a page, makes it - translatable -- this [[ikiwiki/directive]] can be used with an optional `match=PageSpec` - argument, to render translatable a bunch of pages at once +The `PERCENTTRANSLATED` variable is set to the translation +completeness, expressed in percent, on "slave" pages. -Automatic PO files update +One can use it this way: + + +
+ +
+ + +Additional PageSpec tests ------------------------- -Committing changes to a "master" page must: +This plugin enhances the regular [[ikiwiki/PageSpec]] syntax with some +additional tests that are documented [[here|ikiwiki/pagespec/po]]. + +Automatic PO file update +------------------------ + +Committing changes to a "master" page: + +1. updates the POT file and the PO files for the "slave" languages; + the updated PO files are then put under version control; +2. triggers a refresh of the corresponding HTML slave pages. + +Also, when the plugin has just been enabled, or when a page has just +been declared as being translatable, the needed POT and PO files are +created, and the PO files are checked into version control. -1. update the POT file, the PO files for the supported languages, and - put them under version control -2. trigger a refresh of the corresponding HTML slave pages +Discussion pages and other sub-pages +------------------------------------ -The former can be implemented as a `needsbuild` hook, which is the -first type of hook to run after the list of files that need to be -built is known: that is, at a time when we know which "master" page -was modified, and thus, which POT/PO files have to be updated. +Discussion should happen in the language in which the pages are +written for real, *i.e.* the "master" one. If discussion pages are +enabled, "slave" pages therefore link to the "master" page's +discussion page. -The latter can be implemented by making any "slave" page depend on the -corresponding "master" page. The `add_depends` function can achieved -this, if used in a FIXME hook. +Likewise, "slave" pages are not supposed to have sub-pages; +[[WikiLinks|wikilink]] that appear on a "slave" page therefore link to +the master page's sub-pages. -UI consistency: rename "Edit" button on slave pages ---------------------------------------------------- +Translating +----------- + +One can edit the PO files using ikiwiki's CGI (a message-by-message +interface could also be implemented at some point). + +If [[tips/untrusted_git_push]] is setup, one can edit the PO files in one's +preferred `$EDITOR`, without needing to be online. + +Markup languages support +------------------------ + +Markdown is well supported. Some other markup languages supported by +ikiwiki mostly work, but some pieces of syntax are not rendered +correctly on the slave pages: + +* [[reStructuredText|rst]]: anonymous hyperlinks and internal + cross-references +* [[wikitext]]: conversion of newlines to paragraphs +* [[creole]]: verbatim text is wrapped, tables are broken +* [[html]] and LaTeX: not supported yet; the dedicated po4a modules + could be used to support them, but they would need a security audit +* other markup languages have not been tested. + +Security +======== + +[[./security]] contains a detailed security analysis of this plugin +and its dependencies. + +When using po4a older than 0.35, it is recommended to uninstall +`Text::WrapI18N` (Debian package `libtext-wrapi18n-perl`), in order to +avoid a potential denial of service. + +TODO +==== -It may be surprising to some, after having pressed *Edit* on a wiki -page, to end up editing a strange PO file. The *Edit* button must then -be be renamed to *Improve translation* on "slave" pages. +Better links +------------ -Translation quality assurance ------------------------------ +Once the fix to +[[bugs/pagetitle_function_does_not_respect_meta_titles]] from +[[intrigeri]]'s `meta` branch is merged into ikiwiki upstream, the +generated links' text will be optionally based on the page titles set +with the [[meta|plugins/meta]] plugin, and will thus be translatable. +It will also allow displaying the translation status in links to slave +pages. Both were implemented, and reverted in commit +ea753782b222bf4ba2fb4683b6363afdd9055b64, which should be reverted +once [[intrigeri]]'s `meta` branch is merged. -Modifying a PO file via the CGI must only be allowed if the new -version is a valid PO file. As a bonus, check that it provides a more -complete translation than the existing one. +An integration branch, called `meta-po`, merges [[intrigeri]]'s `po` +and `meta` branches, and thus has thise additional features. -A new `cansave` type of hook would be needed to implement this. +Robustness tests +---------------- -Note: committing to the underlying repository is a way to bypass -this check. +### Enabling/disabling the plugin -Translating online ------------------- +* enabling the plugin with `po_translatable_pages` set to blacklist: **OK** +* enabling the plugin with `po_translatable_pages` set to whitelist: **OK** +* enabling the plugin without `po_translatable_pages` set: **OK** +* disabling the plugin: **OK** -As PO is a wiki page type, we already have an online PO editor, that -is ikiwiki's CGI. +### Changing the plugin config -A message-by-message interface could be implemented later, providing -a nice way to translate offline (without VCS access) is provided. +* adding existing pages to `po_translatable_pages`: **OK** +* removing existing pages from `po_translatable_pages`: **OK** +* adding a language to `po_slave_languages`: **OK** +* removing a language from `po_slave_languages`: **OK** +* changing `po_master_language`: **OK** +* replacing `po_master_language` with a language previously part of + `po_slave_languages`: needs two rebuilds, but **OK** (this is quite + a perverse test actually) -Translating offline without VCS access --------------------------------------- +### Creating/deleting/renaming pages -The following workflow should be made possible for translators without -VCS access who need to edit the PO files in another editor than a web -browser: +All cases of master/slave page creation/deletion/rename, both via RCS +and via CGI, have been tested. -- download the PO file for the page -- use any PO editor to update the translation -- upload the updated PO file +### Misc -A generic mechanism to download and upload a page's source is needed. -It's only an alternative way to do Edit/edit/Save. +* general test with `usedirs` disabled: **OK** +* general test with `indexpages` enabled: **not OK** +* general test with `po_link_to=default` with `userdirs` enabled: **OK** +* general test with `po_link_to=default` with `userdirs` disabled: **OK** -### Short-term workflow +Misc. bugs +---------- -- pretend to edit the PO file online -- copy the PO file content from the textarea -- cancel the edit -- paste the content into a local file. +Documentation +------------- +Maybe write separate documentation depending on the people it targets: +translators, wiki administrators, hackers. This plugin may be complex +enough to deserve this.