Changes between Version 2 and Version 3 of TracLinks


Ignore:
Timestamp:
2023-04-20T18:47:43Z (19 months ago)
Author:
trac
Comment:

--

Legend:

Unmodified
Added
Removed
Modified

  • TracLinks

    v2 v3  
    1 = Trac Links =
     1= Trac Links
     2
    23[[TracGuideToc]]
    3 
    4 TracLinks are a fundamental feature of Trac, because they allow easy hyperlinking between the various entities in the system—such as tickets, reports, changesets, Wiki pages, milestones, and source files—from anywhere WikiFormatting is used.
    5 
    6 TracLinks are generally of the form '''type:id''' (where ''id'' represents the
    7 number, name or path of the item) though some frequently used kinds of items
    8 also have short-hand notations.
    9 
    10 Some examples:
    11  * Tickets: '''!#1''' or '''!ticket:1'''
    12  * Ticket comments: '''!comment:ticket:1:2'''
    13  * Reports: '''!{1}''' or '''!report:1'''
    14  * Changesets: '''!r1''', '''![1]''', '''!changeset:1''' or (restricted) '''![1/trunk]''', '''!changeset:1/trunk''', '''![2:5/trunk]'''
    15  * Revision log: '''!r1:3''', '''![1:3]''' or '''!log:@1:3''', '''!log:trunk@1:3'''
    16  * Diffs (requires [milestone:0.10 0.10]): '''!diff:@1:3''', '''!diff:tags/trac-0.9.2/wiki-default//tags/trac-0.9.3/wiki-default''' or '''!diff:trunk/trac@3538//sandbox/vc-refactoring@3539'''
    17  * Wiki pages: '''!CamelCase''' or '''!wiki:CamelCase'''
    18  * Milestones: '''!milestone:1.0'''
    19  * Attachment: '''!attachment:ticket:944:attachment.1073.diff'''
    20  * Files: '''!source:trunk/COPYING'''
    21  * A specific file revision: '''!source:/trunk/COPYING@200'''
    22  * A particular line of a specific file revision: '''!source:/trunk/COPYING@200#L25'''
     4[[PageOutline(2-5,Contents,pullout)]]
     5
     6TracLinks are a fundamental feature of Trac, allowing easy hyperlinking between the various entities in the system — such as tickets, reports, changesets, Wiki pages, milestones, and source files — from anywhere WikiFormatting is used.
     7
     8TracLinks are generally of the form '''type:id''' (where ''id'' represents the number, name or path of the item) though some frequently used kinds of items also have short-hand notations.
     9
     10== Where to use TracLinks
     11
     12You can use TracLinks in:
     13
     14 * Source code (Subversion) commit messages
     15 * Wiki pages
     16 * Full descriptions for tickets, reports and milestones
     17
     18and any other text fields explicitly marked as supporting WikiFormatting.
     19
     20== Overview
     21
     22||= Wiki Markup =||= Display =||
     23{{{#!td
     24 Wiki pages :: `CamelCase` or `wiki:CamelCase`
     25 Parent page :: `[..]`
     26 Tickets :: `#1` or `ticket:1`
     27 Ticket comments :: `comment:1:ticket:2`
     28 Reports :: `{1}` or `report:1`
     29 Milestones :: `milestone:1.0`
     30 Attachment :: `attachment:example.tgz` (for current page attachment), `attachment:attachment.1073.diff:ticket:944` (absolute path)
     31 Changesets :: `r1`, `[1]`, `changeset:1` or (restricted) `[1/trunk]`, `changeset:1/trunk`, `[1/repository]`
     32 Revision log :: `r1:3`, `[1:3]` or `log:@1:3`, `log:trunk@1:3`, `[2:5/trunk]`
     33 Diffs :: `diff:@1:3`, `diff:plugins/0.12/mercurial-plugin@9128:9953`,
     34          `diff:tags/trac-0.9.2/wiki-default//tags/trac-0.9.3/wiki-default`
     35          or `diff:trunk/trac@3538//sandbox/vc-refactoring@3539`
     36 Files :: `source:trunk/COPYING`, `source:/trunk/COPYING@200` (at version 200), `source:/trunk/COPYING@200#L25` (at version 200, line 25), `source:/trunk/COPYING@200:27-30#L25` (at version 200, line 25, highlighting lines 27-30)
     37}}}
     38{{{#!td
     39 Wiki pages :: CamelCase or wiki:CamelCase
     40 Parent page :: [..]
     41 Tickets :: #1 or ticket:1
     42 Ticket comments :: comment:1:ticket:2
     43 Reports :: {1} or report:1
     44 Milestones :: milestone:1.0
     45 Attachment :: attachment:example.tgz (for current page attachment), attachment:attachment.1073.diff:ticket:944 (absolute path)
     46 Changesets :: r1, [1], changeset:1 or (restricted) [1/trunk], changeset:1/trunk, [1/repository]
     47 Revision log :: r1:3, [1:3] or log:@1:3, log:trunk@1:3, [2:5/trunk]
     48 Diffs :: diff:@1:3, diff:plugins/0.12/mercurial-plugin@9128:9953,
     49          diff:tags/trac-0.9.2/wiki-default//tags/trac-0.9.3/wiki-default
     50          or diff:trunk/trac@3538//sandbox/vc-refactoring@3539
     51 Files :: source:trunk/COPYING, source:/trunk/COPYING@200 (at version 200), source:/trunk/COPYING@200#L25 (at version 200, line 25) source:/trunk/COPYING@200:28-31#L25 (at version 200, line 25, highlighting lines 28-31)
     52}}}
     53
     54'''Note:''' The wiki:CamelCase form is rarely used, but it can be convenient to refer to pages whose names do not follow WikiPageNames rules, ie single words, non-alphabetic characters, etc. See WikiPageNames for more about features specific to links to Wiki page names.
     55
     56
     57{{{#!table class=""
     58|||| Trac links using the full (non-shorthand) notation can also be given a custom link title like this: ||
     59{{{#!td
     60{{{
     61[ticket:1 This is a link to ticket number one] or
     62[[ticket:1|This is another link to ticket number one]].
     63}}}
     64}}}
     65{{{#!td
     66[ticket:1 This is a link to ticket number one] or
     67[[ticket:1|This is another link to ticket number one]].
     68}}}
     69|--------------------------------------------------------------------------------------
     70|||| If the title is omitted, only the id (the part after the colon) is displayed:  ||
     71{{{#!td
     72{{{
     73[ticket:1] or [[ticket:2]]
     74}}}
     75}}}
     76{{{#!td
     77[ticket:1] or [[ticket:2]]
     78}}}
     79|--------------------------------------------------------------------------------------
     80|||| `wiki` is the default if the namespace part of a full link is omitted:  ||
     81{{{#!td
     82{{{
     83[SandBox the sandbox] or
     84[[SandBox|the sandbox]]
     85}}}
     86}}}
     87{{{#!td
     88[SandBox the sandbox] or
     89[[SandBox|the sandbox]]
     90}}}
     91|--------------------------------------------------------------------------------------
     92|||| The short form ''realm:target'' can also be wrapped within a <...> pair, [[br]] which allow for arbitrary characters (i.e. anything but >)  ||
     93{{{#!td
     94{{{
     95<wiki:Strange(page@!)>
     96}}}
     97}}}
     98{{{#!td
     99<wiki:Strange(page@!)>
     100}}}
     101|--------------------------------------------------------------------------------------
     102|||| Quoting can be used with the full notation to allow brackets in the label. ||
     103{{{#!td
     104{{{
     105[TracIni#logging-log_type-option "[logging] log_type"]
     106}}}
     107}}}
     108{{{#!td
     109[TracIni#logging-log_type-option "[logging] log_type"]
     110}}}
     111}}}
     112
     113TracLinks are a very simple idea, but actually allow quite a complex network of information. In practice, it's very intuitive and simple to use, and we've found the "link trail" extremely helpful to better understand what's happening in a project or why a particular change was made.
     114
     115== Advanced use of TracLinks
     116
     117=== Relative links
     118
     119To create a link to a [trac:SubWiki SubWiki]-page just use a '/':
     120{{{
     121 WikiPage/SubWikiPage or ./SubWikiPage
     122}}}
     123
     124To link from a [trac:SubWiki SubWiki] page to a parent, simply use a '..':
     125{{{
     126  [..] or [[..]]
     127}}}
     128  [..] or [[..]]
     129
     130To link from a [trac:SubWiki SubWiki] page to a [=#sibling sibling] page, use a '../':
     131{{{
     132  [../Sibling see next sibling] or [[../Sibling|see next sibling]]
     133}}}
     134  [../Sibling see next sibling] or [[../Sibling|see next sibling]]
     135
     136But in practice you often won't need to add the `../` prefix to link to a sibling page.
     137For resolving the location of a wiki link, it's the target page closest in the hierarchy to the page where the link is written which will be selected. So for example, within a sub-hierarchy, a sibling page will be targeted in preference to a top-level page.
     138This makes it easy to copy or move pages to a sub-hierarchy by [[WikiNewPage#renaming|renaming]] without having to adapt the links.
     139
     140To link explicitly to a [=#toplevel toplevel] Wiki page, use the `wiki:/` prefix. Be careful **not** to use the `/` prefix alone, as this corresponds to the [#Server-relativelinks] syntax and with such a link you will lack the `/wiki/` part in the resulting URL. A link such as `[../newticket]` will stay in the wiki namespace and therefore link to a sibling page.
     141
     142=== Link anchors
     143
     144To create a link to a specific anchor in a page, use `#`:
     145{{{
     146 [#Linkanchors Link anchors] or [[#Linkanchors|Link anchors]]
     147}}}
     148  [#Linkanchors Link anchors] or [[#Linkanchors|Link anchors]]
     149
     150To create an anchor in a page, use `[=#...]`:
     151{{{
     152 [=#myanchor my anchor] or empty form [=#myanchor]
     153}}}
     154 [=#myanchor my anchor] or empty form [=#myanchor]
     155
     156Hint: when you hover your mouse over the title of a section, a '¶' character will be displayed. This is a link to that specific section and you can use this to copy the `#...` part inside a relative link to an anchor.
     157
     158To create a link to the first or last occurrence of a term on a page, use a ''pseudo anchor'' starting with `#/` or `#?`:
     159{{{
     160 [#/Milestone first occurrence of Milestone] or
     161 [#?Milestone last occurrence of Milestone]
     162}}}
     163 [#/Milestone first occurrence of Milestone] or
     164 [#?Milestone last occurrence of Milestone]
     165This will also highlight all other matches on the linked page. By default only case sensitive matches are considered. To include case insensitive matches append `/i`:
     166{{{
     167 [#/Milestone/i first occurrence of Milestone or milestone] or
     168 [#?Milestone/i last occurrence of Milestone or milestone]
     169}}}
     170 [#/Milestone/i first occurrence of Milestone or milestone] or
     171 [#?Milestone/i last occurrence of Milestone or milestone]
     172
     173''(since Trac 1.0)''
     174
     175Such anchors can be very useful for linking to specific lines in a file in the source browser:
     176{{{
     177 [trac:source:tags/trac-0.12/trac/wiki/api.py#L127 Line 127] or
     178 [trac:source:tags/trac-0.12/trac/ticket/roadmap.py#L47 Line 47]
     179}}}
     180 [trac:source:tags/trac-0.12/trac/wiki/api.py#L127 Line 127] or
     181 [trac:source:tags/trac-0.12/trac/ticket/roadmap.py#L47 Line 47]
     182(Hint: The line numbers displayed in the source browser are links to anchors on the respective lines.)
     183
     184Since such links become outdated when the file changes, it can be useful to link using a `#/` pseudo anchor instead:
     185{{{
     186 [trac:source:trunk/trac/wiki/api.py#/IWikiSyntaxProvider IWikiSyntaxProvider] or
     187 [trac:source:trunk/trac/env.py#/ISystemInfoProvider ISystemInfoProvider]
     188}}}
     189 [trac:source:trunk/trac/wiki/api.py#/IWikiSyntaxProvider IWikiSyntaxProvider] or
     190 [trac:source:trunk/trac/env.py#/ISystemInfoProvider ISystemInfoProvider]
     191
     192=== InterWiki links
     193
     194Other prefixes can be defined freely and made to point to resources in other Web applications. The definition of those prefixes as well as the URLs of the corresponding Web applications is defined in a special Wiki page, the InterMapTxt page. Note that while this could be used to create links to other Trac environments, there is a more specialized way to register other Trac environments which offers greater flexibility.
     195
     196=== InterTrac links
     197
     198This can be seen as a kind of InterWiki link specialized for targeting other Trac projects.
     199
     200Any type of Trac link can be written in one Trac environment and actually refer to resources in another Trac environment. All that is required is to prefix the Trac link with the name of the other Trac environment followed by a colon. The other Trac environment must be registered on the InterTrac page.
     201
     202A distinct advantage of InterTrac links over InterWiki links is that the shorthand form of Trac links can also be used, such as `{}`, `r`, `#`. For example, if T was set as an alias for Trac, then links to Trac tickets can be written as #T234, and links to Trac changesets can be written as [trac 1508].
     203See InterTrac for the complete details.
     204
     205=== Server-relative links
     206
     207It is often useful to be able to link to objects in your project that have no built-in Trac linking mechanism, such as static resources, `newticket`, a shared `/register` page on the server, etc.
     208
     209To link to resources inside the project, use either an absolute path from the project root, or a relative link from the URL of the current page (''Changed in 0.11''):
     210
     211{{{
     212[/newticket Create a new ticket] or [[//newticket|Create a new ticket]]
     213[/ home] or [[/|home]]
     214}}}
     215
     216Display: [/newticket Create a new ticket] or [[//newticket|Create a new ticket]]
     217[/ home] or [[/|home]]
     218
     219To link to another location on the server (possibly outside the project but on the same host), use the `//` prefix (''Changed in 0.11''):
     220
     221{{{
     222[//register Register Here] or [[//register|Register Here]]
     223}}}
     224
     225Display: [//register Register Here] or [[//register|Register Here]]
     226
     227=== Quoting space in TracLinks
     228
     229Immediately after a TracLinks prefix, targets containing space characters should be enclosed in a pair of quotes or double quotes.
     230Examples:
     231 * !wiki:"The whitespace convention"
     232 * !attachment:'the file.txt' or
     233 * !attachment:"the file.txt"
     234 * !attachment:"the file.txt:ticket:123"
     235
     236Note that by using [trac:WikiCreole] style links, it's quite natural to write links containing spaces:
     237 * ![[The whitespace convention]]
     238 * ![[attachment:the file.txt]]
     239
     240=== Escaping Links
     241
     242To prevent parsing of a !TracLink, you can escape it by preceding it with a '!' (exclamation mark).
     243{{{
     244 !NoLinkHere.
     245 ![42] is not a link either.
     246}}}
     247
    23248Display:
    24  * Tickets: #1 or ticket:1
    25  * Ticket comments: comment:ticket:1:2
    26  * Reports: {1} or report:1
    27  * Changesets: r1, [1], changeset:1, or (restricted) [1/trunk], changeset:1/trunk, [2:5/trunk]
    28  * Revision log: r1:3, [1:3] or log:@1:3, log:trunk@1:3
    29  * Diffs (requires [milestone:0.10 0.10]): diff:@20:30, diff:tags/trac-0.9.2/wiki-default//tags/trac-0.9.3/wiki-default or diff:trunk/trac@3538//sandbox/vc-refactoring/trac@3539
    30  * Wiki pages: CamelCase or wiki:CamelCase
    31  * Milestones: milestone:1.0
    32  * Attachment: attachment:ticket:944:attachment.1073.diff
    33  * Files: source:trunk/COPYING
    34  * A specific file revision: source:/trunk/COPYING@200
    35  * A particular line of a specific file revision: source:/trunk/COPYING@200#L25
    36 
    37 '''Note:''' The wiki:CamelCase form is rarely used, but it can be convenient to refer to
    38 pages whose names do not follow WikiPageNames rules, i.e., single words,
    39 non-alphabetic characters, etc. See WikiPageNames for more about features specific
    40 to links to Wiki page names.
    41 
    42 Trac links using the full (non-shorthand) notation can also be given a custom
    43 link title like this:
    44 
    45 {{{
    46 [ticket:1 This is a link to ticket number one].
    47 }}}
    48 
    49 Display: [ticket:1 This is a link to ticket number one].
    50 
    51 If the title is omitted, only the id (the part after the colon) is displayed:
    52 
    53 {{{
    54 [ticket:1]
    55 }}}
    56 
    57 Display: [ticket:1]
    58 
    59 `wiki` is the default if the namespace part of a full link is omitted (''since version 0.10''):
    60 
    61 {{{
    62 [SandBox the sandbox]
    63 }}}
    64 
    65 Display: [SandBox the sandbox]
    66 
    67 TracLinks are a very simple idea, but actually allow quite a complex network of information. In practice, it's very intuitive and simple to use, and we've found the "link trail" extremely helpful to better understand what's happening in a project or why a particular change was made.
    68 
    69 The following sections describe the individual link types in detail, as well as several notes advanced usage of links.
    70 
    71 == attachment: links ==
     249 !NoLinkHere.
     250 ![42] is not a link either.
     251
     252=== Parameterized Trac links
     253
     254Many Trac resources have more than one way to be rendered, depending on some extra parameters. For example, a Wiki page can accept a `version` or a `format` parameter, a report can make use of dynamic variables, etc.
     255
     256Trac links can support an arbitrary set of parameters, written in the same way as they would be for the corresponding URL. Some examples:
     257 - `wiki:WikiStart?format=txt`
     258 - `ticket:1?version=1`
     259 - `[/newticket?component=module1 create a ticket for module1]`
     260 - `[/newticket?summary=Add+short+description+here create a ticket with URL with spaces]`
     261
     262== TracLinks Reference
     263
     264The following sections describe the individual link types in detail, as well as notes on advanced usage of links.
     265
     266=== attachment: links
    72267
    73268The link syntax for attachments is as follows:
    74  * !attachment:the_file.txt creates a link to the attachment the_file.txt of the current object
    75  * !attachment:wiki:MyPage:the_file.txt creates a link to the attachment the_file.txt of the !MyPage wiki page
    76  * !attachment:ticket:753:the_file.txt creates a link to the attachment the_file.txt of the ticket 753
    77 
    78 == source: links ==
    79 
    80 The default behavior for a source:/some/path link is to open the directory browser
    81 if the path points to a directory and otherwise open the log view.
     269 * !attachment:the_file.txt creates a link to the attachment the_file.txt of the current page
     270 * !attachment:the_file.txt:wiki:MyPage creates a link to the attachment the_file.txt of the !MyPage wiki page
     271 * !attachment:the_file.txt:ticket:753 creates a link to the attachment the_file.txt of the ticket 753
     272
     273Note that the older way, putting the filename at the end, is still supported: !attachment:ticket:753:the_file.txt, but is not recommended.
     274
     275If you'd like to create a direct link to the content of the attached file instead of a link to the attachment page, simply use `raw-attachment:` instead of `attachment:`.
     276
     277This can be useful for pointing directly to an HTML document, for example. Note that for this use case, you'd have to allow the web browser to render the content by setting [[TracIni#attachment-render_unsafe_content-option|"[attachment] render_unsafe_content"]] = `enabled`. Caveat: only do that in environments for which you're 100% confident you can trust the people who are able to attach files, as this opens up your site to [https://en.wikipedia.org/wiki/Cross-site_scripting cross-site scripting] attacks.
     278
     279See also [#export:links].
     280
     281=== comment: links
     282
     283When you're inside a given ticket, you can simply write e.g. !comment:3 to link to the third change comment.
     284It is possible to link to a comment of a specific ticket from anywhere using one of the following syntax:
     285 - `comment:3:ticket:123`
     286 - `ticket:123#comment:3` (note that you can't write `#123#!comment:3`!)
     287It is also possible to link to the ticket's description using one of the following syntax:
     288 - `comment:description` (within the ticket)
     289 - `comment:description:ticket:123`
     290 - `ticket:123#comment:description`
     291
     292=== htdocs: links
     293
     294Use `htdocs:path/to/file` to reference files in the `htdocs` directory of the Trac environment, the [TracEnvironment#DirectoryStructure web resource directory].
     295
     296=== query: links
     297
     298See TracQuery#UsingTracLinks and [#ticket:links].
     299
     300=== search: links
     301
     302See TracSearch#SearchTracLinks
     303
     304=== ticket: links
     305
     306 ''aliases:'' `bug:`, `issue:`
     307
     308Besides the obvious `ticket:id` form, it is also possible to specify a list of tickets or even a range of tickets instead of the `id`. This generates a link to a custom query view containing this fixed set of tickets.
     309
     310Example:
     311 - `ticket:5000-6000`
     312 - `ticket:1,150`
     313
     314=== timeline: links
     315
     316Links to the timeline can be created by specifying a date in the ISO:8601 format. The date can be optionally followed by a time specification. The time is interpreted as being UTC time, but if you don't want to compute the UTC time, you can specify a local time followed by your timezone offset relative to UTC.
     317
     318Examples:
     319 - `timeline:2008-01-29`
     320 - `timeline:2008-01-29T15:48`
     321 - `timeline:2008-01-29T15:48Z`
     322 - `timeline:2008-01-29T16:48+01`
     323 - `timeline:2008-01-29T16:48+0100`
     324 - `timeline:2008-01-29T16:48+01:00`
     325
     326=== wiki: links
     327
     328See WikiPageNames and [#QuotingspaceinTracLinks quoting space in TracLinks] above. It is possible to create a link to a specific page revision using the syntax WikiStart@1.
     329
     330=== Version Control system links
     331
     332It should be noted that multiple repository support works by creating a kind of virtual namespace for versioned files in which the toplevel folders correspond to the repository names. Therefore, in presence of multiple repositories, a ''/path'' specification in the syntax of links detailed below should start with the name of the repository. If omitted, the default repository is used. In case a toplevel folder of the default repository has the same name as a repository, the link directs to the latter. One can always access such folder by fully qualifying it. The default repository can be an alias of a named repository, or conversely, there may be one or more aliases for the default repository, ask your Trac administrator.
     333
     334For example, `source:/trunk/COPYING` targets the path `/trunk/COPYING` in the default repository, whereas `source:/projectA/trunk/COPYING` targets the path `/trunk/COPYING` in the repository named `projectA`. This can be the same file if `'projectA'` is an alias to the default repository or if `''` (the default repository) is an alias to `'projectA'`.
     335
     336==== source: links
     337
     338 ''aliases:'' `browser:`, `repos:`
     339
     340The default behavior for a `source:/some/path link` is to open the browser in that directory directory if the path points to a directory or to show the latest content of the file.
    82341
    83342It's also possible to link directly to a specific revision of a file like this:
    84343 - `source:/some/file@123` - link to the file's revision 123
    85344 - `source:/some/file@head` - link explicitly to the latest revision of the file
     345 - `source:/some/file@named-branch` - link to latest revision of the specified file in `named-branch` (DVCS such as Git or Mercurial)
    86346
    87347If the revision is specified, one can even link to a specific line number:
    88348 - `source:/some/file@123#L10`
    89349 - `source:/tag/0.10@head#L10`
     350 - `source:/some/file@named-branch#L10`
    90351
    91352Finally, one can also highlight an arbitrary set of lines:
    92  - `source:/some/file@123:10-20,100,103#L99` - highlight lines 10 to 20, and lines 100 and 103.
    93 ''(since 0.11)''
    94 
    95 == export: links ==
     353 - `source:/some/file@123:10-20,100,103#L99` - highlight lines 10 to 20, and lines 100 and 103, and target line 99
     354 - or without version number (the `@` is still needed): `source:/some/file@:10-20,100,103#L99`. Version can be omitted when the path is pointing to a source file that will no longer change (like `source:/tags/...`), otherwise it's better to specify which lines of //which version// of the file you're talking about.
     355
     356Note that in presence of multiple repositories, the name of the repository is simply integrated in the path you specify for `source:` (e.g. `source:reponame/trunk/README`). ''(since 0.12)''
     357
     358==== export: links
    96359
    97360To force the download of a file in the repository, as opposed to displaying it in the browser, use the `export` link.  Several forms are available:
    … …  
    99362 * `export:123:/some/file` - get revision 123 of the specified file
    100363 * `export:/some/file@123` - get revision 123 of the specified file
    101 
    102 This can be very useful for displaying HTML documentation with correct stylesheets and images, in case that has been checked in the repository.
    103 
    104 If the path is to a directory in the repository instead of a specific file, the source browser will be used to display the directory (identical to the result of `source:/some/dir`.
    105 
    106 == search: and query: links ==
    107 
    108 See TracSearch#SearchLinks and TracQuery#UsingTracLinks
    109 
    110 == !SubWiki links ==
    111 To create a SubWiki link to a SubWiki-page just use a '/':
    112 {{{
    113  [wiki:WikiPage/SubWikiPage].
    114 }}}
    115 
    116 == InterWiki links ==
    117 
    118 Other prefixes can be defined freely and made to point to resources in other Web applications. The definition of those prefixes as well as the URLs of the corresponding Web applications is defined in a special Wiki page, the InterMapTxt page. Note that while this could be used to create links to other Trac environments, there's a more specialized way to register other Trac environments which offers greater flexibility.
    119 
    120 == InterTrac links ==
    121 
    122 Any of the above form of Trac links could be written in one Trac environment and actually refer to resources present in another Trac environment, provided the Trac link is prefixed by the name of that other Trac environment followed by a colon. That other Trac environment must be registered. See InterTrac for details.
    123 
    124 
    125 == Server-relative links ==
    126 
    127 It is often useful to be able to link to objects on your server that have no built-in
    128 Trac linking mechanism, such as static resources, a `/register` page, etc. This
    129 can be achieved by simply using either an absolute path from the server root,
    130 or a relative link from the URL of the current page:
    131 
    132 {{{
    133 [../newticket newticket]
    134 [/ home]
    135 }}}
    136 
    137 Display: [../newticket newticket] [/ home]
    138 
    139 == Quoting space in TracLinks ==
    140 
    141 Immediately after a TracLinks prefix, targets containing space characters should
    142 be enclosed in a pair of quotes or double quotes.
    143 Examples:
    144  * !wiki:"The whitespace convention"
    145  * !attachment:'the file.txt' or
    146  * !attachment:"the file.txt"
    147  * !attachment:"ticket:123:the file.txt"
    148 
    149 == Where to use TracLinks ==
    150 You can use TracLinks in:
    151 
    152  * Source code (Subversion) commit messages
    153  * Wiki pages
    154  * Full descriptions for tickets, reports and milestones
    155 
    156 and any other text fields explicitly marked as supporting WikiFormatting.
    157 
    158 == Escaping Links ==
    159 
    160 To prevent parsing of a !TracLink, you can escape it by preceding it with a '!' (exclamation mark).
    161 {{{
    162  !NoLinkHere.
    163  ![42] is not a link either.
    164 }}}
    165 
    166 Display:
    167  !NoLinkHere.
    168  ![42] is not a link either.
     364 * `export:/some/file@named-branch` - get latest revision of the specified file in `named-branch` (DVCS such as Git or Mercurial).
     365
     366This can be very useful for displaying XML or HTML documentation with correct stylesheets and images, in case that has been checked in into the repository. Note that for this use case, you'd have to allow the web browser to render the content by setting [[TracIni#browser-render_unsafe_content-option|"[browser] render_unsafe_content"]] = `enabled`, otherwise Trac will force the files to be downloaded as attachments for security concerns.
     367
     368If the path is to a directory in the repository instead of a specific file, the source browser will be used to display the directory (identical to the result of `source:/some/dir`).
     369
     370==== log: links
     371
     372The `log:` links are used to display revision ranges. In its simplest form, it can link to the latest revisions of the specified path, but it can also support displaying an arbitrary set of revisions.
     373 - `log:/` - the latest revisions starting at the root of the repository
     374 - `log:/trunk/tools` - the latest revisions in `trunk/tools`
     375 - `log:/trunk/tools@10000` - the revisions in `trunk/tools` starting from  revision 10000
     376 - `log:@20788,20791:20795` - list revision 20788 and the revisions from 20791 to 20795
     377 - `log:/trunk/tools@20788,20791:20795` - list revision 20788 and the revisions from 20791 to 20795 which affect the given path
     378 - `log:/tools@named-branch` - the revisions in `tools` starting from the latest revision in `named-branch` (DVCS such as Git or Mercurial)
     379
     380There are short forms for revision ranges as well:
     381 - `[20788,20791:20795]`
     382 - `[20788,20791:20795/trunk/tools]`
     383 - `r20791:20795` (but not `r20788,20791:20795` nor `r20791:20795/trunk`)
     384
     385Finally, note that in all of the above, a revision range can be written either as `x:y` or `x-y`.
     386
     387==== Multi-repository links
     388
     389In the presence of multiple repositories, the name of the repository should be specified as the first part of the path:
     390- `log:repos/branch`
     391- `[20-40/repos]`
     392- `r20/repos`
    169393
    170394----
    171395See also: WikiFormatting, TracWiki, WikiPageNames, InterTrac, InterWiki
    172