1 [[!template id=plugin name=po core=0 author="[[intrigeri]]"]]
4 This plugin adds support for multi-lingual wikis, translated with
5 gettext, using [po4a](http://po4a.alioth.debian.org/).
7 It depends on the Perl `Locale::Po4a::Po` library (`apt-get install po4a`).
8 As detailed bellow in the security section, `po4a` is subject to
9 denial-of-service attacks before version 0.35.
16 A language is chosen as the "master" one, and any other supported
17 language is a "slave" one.
19 A page written in the "master" language is a "master" page. It can be
20 of any page type supported by ikiwiki, except `po`. It does not have to be
21 named a special way: migration to this plugin does not imply any page
24 Example: `bla/page.mdwn` is a "master" Markdown page written in
25 English; if `usedirs` is enabled, it is rendered as
26 `bla/page/index.en.html`, else as `bla/page.en.html`.
28 Any translation of a "master" page into a "slave" language is called
29 a "slave" page; it is written in the gettext PO format. `po` is now
30 a page type supported by ikiwiki.
32 Example: `bla/page.fr.po` is the PO "message catalog" used to
33 translate `bla/page.mdwn` into French; if `usedirs` is enabled, it is
34 rendered as `bla/page/index.fr.html`, else as `bla/page.fr.html`
39 This plugin does not support the `indexpages` mode. If you don't know
40 what it is, you probably don't care.
49 `po_master_language` is used to set the "master" language in
50 `ikiwiki.setup`, such as:
52 po_master_language => { 'code' => 'en', 'name' => 'English' }
54 `po_slave_languages` is used to set the list of supported "slave"
57 po_slave_languages => { 'fr' => 'Français',
62 Decide which pages are translatable
63 -----------------------------------
65 The `po_translatable_pages` setting configures what pages are
66 translatable. It is a [[ikiwiki/PageSpec]], so you have lots of
67 control over what kind of pages are translatable.
69 The `.po` files are not considered as being translatable, so you don't need to
70 worry about excluding them explicitly from this [[ikiwiki/PageSpec]].
77 The `po_link_to` option in `ikiwiki.setup` is used to decide how
78 internal links should be generated, depending on web server features
79 and site-specific preferences.
81 #### Default linking behavior
83 If `po_link_to` is unset, or set to `default`, ikiwiki's default
84 linking behavior is preserved: `\[[destpage]]` links to the master
87 #### Link to current language
89 If `po_link_to` is set to `current`, `\[[destpage]]` links to the
90 `destpage`'s version written in the current page's language, if
93 * `foo/destpage/index.LL.html` if `usedirs` is enabled
94 * `foo/destpage.LL.html` if `usedirs` is disabled
96 #### Link to negotiated language
98 If `po_link_to` is set to `negotiated`, `\[[page]]` links to the
99 negotiated preferred language, *i.e.* `foo/page/`.
101 (In)compatibility notes:
103 * if `usedirs` is disabled, it does not make sense to set `po_link_to`
104 to `negotiated`; this option combination is neither implemented
106 * if the web server does not support Content Negotiation, setting
107 `po_link_to` to `negotiated` will produce a unusable website.
115 Using Apache `mod_negotiation` makes it really easy to have Apache
116 serve any page in the client's preferred language, if available.
117 This is the default Debian Apache configuration.
119 When `usedirs` is enabled, one has to set `DirectoryIndex index` for
122 Setting `DefaultLanguage LL` (replace `LL` with your default MIME
123 language code) for the wiki context can help to ensure
124 `bla/page/index.en.html` is served as `Content-Language: LL`.
129 lighttpd unfortunately does not support content negotiation.
131 **FIXME**: does `mod_magnet` provide the functionality needed to
141 When `po_link_to` is not set to `negotiated`, one should replace some
142 occurrences of `BASEURL` with `HOMEPAGEURL` to get correct links to
145 The `ISTRANSLATION` and `ISTRANSLATABLE` variables can be used to
146 display things only on translatable or translation pages.
148 ### Display page's versions in other languages
150 The `OTHERLANGUAGES` loop provides ways to display other languages'
151 versions of the same page, and the translations' status.
153 An example of its use can be found in the default
154 `templates/page.tmpl`. In case you want to customize it, the following
155 variables are available inside the loop (for every page in):
157 * `URL` - url to the page
158 * `CODE` - two-letters language code
159 * `LANGUAGE` - language name (as defined in `po_slave_languages`)
160 * `MASTER` - is true (1) if, and only if the page is a "master" page
161 * `PERCENT` - for "slave" pages, is set to the translation completeness, in percents
163 ### Display the current translation status
165 The `PERCENTTRANSLATED` variable is set to the translation
166 completeness, expressed in percent, on "slave" pages. It is used by
167 the default `templates/page.tmpl`.
169 Additional PageSpec tests
170 -------------------------
172 This plugin enhances the regular [[ikiwiki/PageSpec]] syntax with some
173 additional tests that are documented [[here|ikiwiki/pagespec/po]].
175 Automatic PO file update
176 ------------------------
178 Committing changes to a "master" page:
180 1. updates the POT file and the PO files for the "slave" languages;
181 the updated PO files are then put under version control;
182 2. triggers a refresh of the corresponding HTML slave pages.
184 Also, when the plugin has just been enabled, or when a page has just
185 been declared as being translatable, the needed POT and PO files are
186 created, and the PO files are checked into version control.
188 Discussion pages and other sub-pages
189 ------------------------------------
191 Discussion should happen in the language in which the pages are
192 written for real, *i.e.* the "master" one. If discussion pages are
193 enabled, "slave" pages therefore link to the "master" page's
196 Likewise, "slave" pages are not supposed to have sub-pages;
197 [[WikiLinks|wikilink]] that appear on a "slave" page therefore link to
198 the master page's sub-pages.
203 One can edit the PO files using ikiwiki's CGI (a message-by-message
204 interface could also be implemented at some point).
206 If [[tips/untrusted_git_push]] is setup, one can edit the PO files in one's
207 preferred `$EDITOR`, without needing to be online.
209 Markup languages support
210 ------------------------
212 [[Markdown|mdwn]] is well supported. Some other markup languages supported
213 by ikiwiki mostly work, but some pieces of syntax are not rendered
214 correctly on the slave pages:
216 * [[reStructuredText|rst]]: anonymous hyperlinks and internal
218 * [[wikitext]]: conversion of newlines to paragraphs
219 * [[creole]]: verbatim text is wrapped, tables are broken
220 * [[html]] and LaTeX: not supported yet; the dedicated po4a modules
221 could be used to support them, but they would need a security audit
222 * other markup languages have not been tested.
227 [[po/discussion]] contains a detailed security analysis of this plugin
228 and its dependencies.
230 When using po4a older than 0.35, it is recommended to uninstall
231 `Text::WrapI18N` (Debian package `libtext-wrapi18n-perl`), in order to
232 avoid a potential denial of service.
241 [[bugs/pagetitle_function_does_not_respect_meta_titles]] from
242 [[intrigeri]]'s `meta` branch is merged into ikiwiki upstream, the
243 generated links' text will be optionally based on the page titles set
244 with the [[meta|plugins/meta]] plugin, and will thus be translatable.
245 It will also allow displaying the translation status in links to slave
246 pages. Both were implemented, and reverted in commit
247 ea753782b222bf4ba2fb4683b6363afdd9055b64, which should be reverted
248 once [[intrigeri]]'s `meta` branch is merged.
250 An integration branch, called `meta-po`, merges [[intrigeri]]'s `po`
251 and `meta` branches, and thus has this additional features.
256 If a page contains a WikiLink to itself, ikiwiki does not normally
257 turn that into a hyperlink. However, if a translated page contains a
258 WikiLink to itself, a hyperlink is inserted, at least with the default
259 `po_link_to` the link points to the English version of the page. Is there a
260 good reason for that to be done? --[[Joey]]
262 Language display order
263 ----------------------
265 Jonas pointed out that one might want to control the order that links to
266 other languages are listed, for various reasons. Currently, there is no
267 order, as `po_slave_languages` is a hash. It would need to be converted
268 to an array to support this. (If twere done, twere best done quickly.)
274 I notice code in the scan hook that seems to assume
275 that %links will accumulate duplicate links for a page.
276 That used to be so, but the bug was fixed. Does this mean
277 that po might be replacing the only link on a page, in error?
280 Name of toplevel index page
281 ---------------------------
283 Normally at the top index page of a wiki, you see the wiki name at
284 the top. However, at the top *translated* index page, you see something
285 like "index.da". --[[Joey]]
290 I was suprised that, when using the map directive, a pagespec of "*"
291 listed all the translated pages as well as regular pages. That can
292 make a big difference to an existing wiki when po is turned on,
293 and seems generally not wanted.
294 (OTOH, you do want to match translated pages by
295 default when locking pages.) --[[Joey]]
297 Edit links on untranslated pages
298 --------------------------------
300 If a page is not translated yet, the "translated" version of it
301 displays wikilinks to other, existing (but not yet translated?)
302 pages as edit links, as if those pages do not exist.
304 That's really confusing, especially as clicking such a link
305 brings up an edit form to create a new, english page.
307 This is with po_link_to=current. With default, it doesn't happen..
309 Double commits of po files
310 --------------------------
312 When adding a new english page, the po files are created, committed,
313 and then committed again. The second commit makes this change:
315 -"Content-Type: text/plain; charset=utf-8\n"
316 -"Content-Transfer-Encoding: ENCODING"
317 +"Content-Type: text/plain; charset=UTF-8\n"
318 +"Content-Transfer-Encoding: ENCODING\n"
320 Same thing happens when a change to an existing page triggers a po file
326 Maybe write separate documentation depending on the people it targets:
327 translators, wiki administrators, hackers. This plugin may be complex
328 enough to deserve this.