X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/d4f787ef528d9947473b4b99d1088b647d615200..5b8ffe3111737eaf5efe3f5699fcc936b9fd4e62:/doc/plugins/po.mdwn?ds=sidebyside diff --git a/doc/plugins/po.mdwn b/doc/plugins/po.mdwn index 06ecedc24..57459c1ef 100644 --- a/doc/plugins/po.mdwn +++ b/doc/plugins/po.mdwn @@ -5,6 +5,10 @@ This plugin adds support for multi-lingual wikis, translated with 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 ============ @@ -12,9 +16,9 @@ Introduction 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, and is -written in any supported format but PO. It does not have to be named -a special way: migration from/to this plugin does not imply heavy +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 @@ -22,18 +26,27 @@ English; if `usedirs` is enabled, it is rendered as `bla/page/index.en.html`, else as `bla/page.en.html`. 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 "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.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' } @@ -42,7 +55,7 @@ Configuration languages, such as: po_slave_languages => { 'fr' => 'Français', - 'es' => 'Castellano', + 'es' => 'Español', 'de' => 'Deutsch', } @@ -53,68 +66,45 @@ 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 `*.LL.po` translations files are anyway not considered as being -translatable, so you don't need to worry about excluding them manually -from this [[ikiwiki/PageSpec]]. +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 -------------- -One can use the `po_link_to_` option in `ikiwiki.setup` to choose how +### 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 +#### Default linking behavior If `po_link_to` is unset, or set to `default`, ikiwiki's default -linking behavior is preserved: `\[[page]]` links to the master +linking behavior is preserved: `\[[destpage]]` links to the master language's page. -### 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: - -- `po_link_to => negotiated` provides no useful behavior if `usedirs` - is disabled; this option combination is neither implemented nor - allowed -- `po_link_to => negotiated` provides no useful behavior if the web - server does not support Content Negotiation - -### Link to current language +#### Link to current language -If `po_link_to` is set to `current` and the destination page is either -a translatable page or a translation, `\[[page]]` links to the current -page's language, *i.e.*: +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/page/index.LL.html` if `usedirs` is enabled -- `foo/page.LL.html` if `usedirs` is disabled +* `foo/destpage/index.LL.html` if `usedirs` is enabled +* `foo/destpage.LL.html` if `usedirs` is disabled +#### Link to negotiated language -Templates ---------- +If `po_link_to` is set to `negotiated`, `\[[page]]` links to the +negotiated preferred language, *i.e.* `foo/page/`. -The `OTHERLANGUAGES` loop provides ways to display the existing -translations and/or master page. One typically adds the following code -to `templates/page.tmpl`: - - -
- -
- +(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 ============== @@ -122,17 +112,19 @@ 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. + +Add 'Options MultiViews' to the wiki directory's configuration in Apache. 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 +language code) for the wiki context can help to ensure `bla/page/index.en.html` is served as `Content-Language: LL`. -**FIXME**: is it still needed with the new `.en.html` naming convention? + +For details, see [Apache's documentation](http://httpd.apache.org/docs/2.2/content-negotiation.html). lighttpd -------- @@ -143,111 +135,191 @@ lighttpd unfortunately does not support content negotiation. emulate this? -TODO -==== +Usage +===== + +Templates +--------- -Link relationships ------------------- +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. -Should pages using the `OTHERLANGUAGES` template loop be declared as -linking to the same page in other versions? +The `ISTRANSLATION` and `ISTRANSLATABLE` variables can be used to +display things only on translatable or translation pages. -View translation status ------------------------ +### Display page's versions in other languages -One should be able to view some information about the translation -completeness, either for a given page or for the whole wiki. +The `OTHERLANGUAGES` loop provides ways to display other languages' +versions of the same page, and the translations' status. -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. +An example of its use can be found in the default +`templates/page.tmpl`. In case you want to customize it, the following +variables are available inside the loop (for every page in): -If it's not too heavy to compute, this status data may be made -available in the `OTHERLANGUAGES` template loop; else, a dedicated -loop would be needed. +* `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 -Automatic PO files update +### Display the current translation status + +The `PERCENTTRANSLATED` variable is set to the translation +completeness, expressed in percent, on "slave" pages. It is used by +the default `templates/page.tmpl`. + +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 and the PO files for the supported languages; - this is done in the `needsbuild` hook; the updated PO files must - then be put under version control +Discussion pages and other sub-pages +------------------------------------ -2. trigger a refresh of the corresponding HTML slave pages: this is - achieved by making any "slave" page dependent on the corresponding - "master" page, in the `needsbuild` hook. +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. -Also, when the plugin has just been enabled, all the needed POT and PO -files have to be created. +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 +----------- -It may be surprising to some, after having pressed *Edit* on a wiki -page, to end up editing a strange looking PO file. The *Edit* button -displayed on "slave" pages must therefore be renamed *Improve -translation* . +One can edit the PO files using ikiwiki's CGI (a message-by-message +interface could also be implemented at some point). -Pages selection depending on language -------------------------------------- +If [[tips/untrusted_git_push]] is setup, one can edit the PO files in one's +preferred `$EDITOR`, without needing to be online. -To improve user navigation in a multi-lingual wiki, site developers -must be enabled to write: +Markup languages support +------------------------ - \[[!map pages="dev/* and lang(LL)" feeds="no"]] +[[Markdown|mdwn]] 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: - \[[!map pages="dev/* and currentlang()" feeds="no"]] +* [[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. -Translation quality assurance ------------------------------ +Security +======== -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. +[[po/discussion]] contains a detailed security analysis of this plugin +and its dependencies. -A new `cansave` type of hook would be needed to implement this. +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. -Note: committing to the underlying repository is a way to bypass -this check. +TODO +==== + +Better links +------------ -Translating online ------------------- +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. -As PO is a wiki page type, we already have an online PO editor, that -is ikiwiki's CGI. +An integration branch, called `meta-po`, merges [[intrigeri]]'s `po` +and `meta` branches, and thus has this additional features. -A message-by-message interface could also be implemented at some -point; a nice way to do offline translation work (without VCS access) -still has to be offered, though. +Language display order +---------------------- + +Jonas pointed out that one might want to control the order that links to +other languages are listed, for various reasons. Currently, there is no +order, as `po_slave_languages` is a hash. It would need to be converted +to an array to support this. (If twere done, twere best done quickly.) +--[[Joey]] + +Pagespecs +--------- -Translating offline without VCS access --------------------------------------- +I was suprised that, when using the map directive, a pagespec of "*" +listed all the translated pages as well as regular pages. That can +make a big difference to an existing wiki when po is turned on, +and seems generally not wanted. +(OTOH, you do want to match translated pages by +default when locking pages.) --[[Joey]] -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: +Edit links on untranslated pages +-------------------------------- -- download the page's PO file -- use any PO editor to update the translation -- upload the updated PO file +If a page is not translated yet, the "translated" version of it +displays wikilinks to other, existing (but not yet translated?) +pages as edit links, as if those pages do not exist. + +That's really confusing, especially as clicking such a link +brings up an edit form to create a new, english page. + +This is with po_link_to=current or negotiated. With default, it doesn't +happen.. + +Also, this may only happen if the page being linked to is coming from an +underlay, and the underlays lack translation to a given language. +--[[Joey]] + +Double commits of po files +-------------------------- + +When adding a new english page, the po files are created, committed, +and then committed again. The second commit makes this change: + + -"Content-Type: text/plain; charset=utf-8\n" + -"Content-Transfer-Encoding: ENCODING" + +"Content-Type: text/plain; charset=UTF-8\n" + +"Content-Transfer-Encoding: ENCODING\n" + +Same thing happens when a change to an existing page triggers a po file +update. --[[Joey]] + +Ugly messages with empty files +------------------------------ + +If there are empty .mdwn files, the po plugin displays some ugly messages. + +Translation of directives +------------------------- -Implementation note: a generic mechanism to upload a page's source is -needed: it's only an alternative way to allow saving a the modified -page's source with the CGI. +If a translated page contains a directive, it may expand to some english +text, or text in whatever single language ikiwiki is configured to "speak". -### Short-term workflow +Maybe there could be a way to switch ikiwiki to speaking another language +when building a non-english page? Then the directives would get translated. -A possible workaround is: +Documentation +------------- -- 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. -- edit the local file in any PO editor -- pretend to edit the PO file online -- paste the modified local file's content into the edit textarea -- save +Maybe write separate documentation depending on the people it targets: +translators, wiki administrators, hackers. This plugin may be complex +enough to deserve this.