Trac Links

Table of Contents

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.

TracLinks 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.

You can use TracLinks in:

  • Source code (Subversion) commit messages
  • Wiki pages
  • Full descriptions for tickets, reports and milestones

and any other text fields explicitly marked as supporting WikiFormatting.

Some examples:

  • Tickets: #1 or ticket:1
  • Ticket comments: comment:ticket:1:2
  • Reports: {1} or report:1
  • Changesets: !r1, ![1], changeset:1 or (restricted) ![1/trunk], changeset:1/trunk, [2:5/trunk]
  • Revision log: r1:3, [1:3] or log:@1:3, log:trunk@1:3
  • Diffs (requires 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
  • Wiki pages: CamelCase or wiki:CamelCase
  • Parent page: [..]
  • Milestones: milestone:1.0
  • Attachment: attachment:ticket:944:attachment.1073.diff
  • Files: source:trunk/COPYING
  • A specific file revision: source:/trunk/COPYING@200
  • A particular line of a specific file revision: source:/trunk/COPYING@200#L25

Display:

  • Tickets: #1 or ticket:1
  • Ticket comments: comment:ticket:1:2
  • Reports: {1} or report:1
  • Changesets: r1, [1], changeset:1, or (restricted) [1/trunk], changeset:1/trunk, [2:5/trunk]
  • Revision log: r1:3, [1:3] or log:@1:3, log:trunk@1:3
  • Diffs (requires 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
  • Wiki pages: CamelCase or wiki:CamelCase
  • Parent page: ..
  • Milestones: milestone:1.0
  • Attachment: attachment:ticket:944:attachment.1073.diff
  • Files: source:trunk/COPYING
  • A specific file revision: source:/trunk/COPYING@200
  • A particular line of a specific file revision: source:/trunk/COPYING@200#L25

Note: The wiki:CamelCase form is rarely used, but it can be convenient to refer to pages whose names do not follow WikiPageNames rules, i.e., single words, non-alphabetic characters, etc. See WikiPageNames for more about features specific to links to Wiki page names.

Trac links using the full (non-shorthand) notation can also be given a custom link title like this: 

[ticket:1 This is a link to ticket number one].

Display: This is a link to ticket number one.

If the title is omitted, only the id (the part after the colon) is displayed: 

[ticket:1]

Display: 1

wiki is the default if the namespace part of a full link is omitted (since version 0.10): 

[SandBox the sandbox]

Display: the sandbox

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.

To create a link to a specific anchor in a page, use '#': 

 [#Relativelinks relative links]

Displays:

relative links

Hint: when you move 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.

To create a link to a SubWiki?-page just use a '/': 

 WikiPage/SubWikiPage or ./SubWikiPage

To link from a SubWiki? page to a parent, simply use a '..': 

  [..]

To link from a SubWiki? page to a sibling page, use a '../': 

  [../Sibling see next sibling]

(Changed in 0.11) Note that in Trac 0.10, using e.g. [../newticket] may have worked for linking to the /newticket top-level URL, but now in 0.11 it will stay in the wiki namespace and link to a sibling page. See #Server-relativelinks for the new syntax.

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.

This can be seen as a kind of InterWiki link specialized for targeting other Trac projects.

Any type 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, under its name or an alias. See InterTrac for details.

A distinctive advantage of InterTrac links over InterWiki links is that the shorthand form of Trac links usually have a way to understand the InterTrac prefixes. For example, links to Trac tickets can be written #T234 (if T was set as an alias for Trac), links to Trac changesets can be written [trac 1508].

It 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.

To 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): 

[/newticket Create a new ticket]
[/ home]

Display: newticket? home

To link to another location on the server (outside the project), use the '//location' link syntax (Changed in 0.11): 

[//register Register Here]

Display: Register Here

Immediately after a TracLinks prefix, targets containing space characters should be enclosed in a pair of quotes or double quotes. Examples:

  • wiki:"The whitespace convention"
  • attachment:'the file.txt' or
  • attachment:"the file.txt"
  • attachment:"ticket:123:the file.txt"

To prevent parsing of a TracLink, you can escape it by preceding it with a '!' (exclamation mark). 

 !NoLinkHere.
 ![42] is not a link either.

Display:

NoLinkHere. ![42] is not a link either.

The Trac links target Trac resources which have generally more than one way to be rendered, according to 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.

Any Trac links can support an arbitrary set of parameters, written in the same way as they would be for the corresponding URL. Some examples:

  • wiki:WikiStart?format=txt
  • ticket:1?version=1
  • [/newticket?component=module1 create a ticket for module1]

TracLinks Reference

The following sections describe the individual link types in detail, as well as several notes advanced usage of links.

The link syntax for attachments is as follows:

  • attachment:the_file.txt creates a link to the attachment the_file.txt of the current object
  • attachment:wiki:MyPage:the_file.txt creates a link to the attachment the_file.txt of the MyPage wiki page
  • attachment:ticket:753:the_file.txt creates a link to the attachment the_file.txt of the ticket 753

See TracQuery#UsingTracLinks and #ticket:links.

See TracSearch#SearchLinks

Besides 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.

Example:

  • ticket:5000-6000
  • ticket:1,150

(since Trac 0.11)

Links 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 alternatively you can specify your local time, followed by your timezone if you don't want to compute the UTC time.

Examples:

  • timeline:2008-01-29
  • timeline:2008-01-29T15:48
  • timeline:2008-01-29T16:48Z+01

(since Trac 0.11)

See WikiPageNames and quoting space in TracLinks above.

The default behavior for a source:/some/path link is to open the directory browser if the path points to a directory and otherwise open the log view.

It's also possible to link directly to a specific revision of a file like this:

  • source:/some/file@123 - link to the file's revision 123
  • source:/some/file@head - link explicitly to the latest revision of the file

If the revision is specified, one can even link to a specific line number:

  • source:/some/file@123#L10
  • source:/tag/0.10@head#L10

Finally, one can also highlight an arbitrary set of lines:

  • source:/some/file@123:10-20,100,103#L99 - highlight lines 10 to 20, and lines 100 and 103.

(since 0.11)

To 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:

  • export:/some/file - get the HEAD revision of the specified file
  • export:123:/some/file - get revision 123 of the specified file
  • export:/some/file@123 - get revision 123 of the specified file

This can be very useful for displaying HTML documentation with correct stylesheets and images, in case that has been checked in the repository.

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.

The log: links are used to display revision ranges. In its simplest form, it can link to the latest revisions from the specified path, but it can also support displaying an arbitrary set of revisions.

  • log:/ - the latest revisions starting at the root of the repository
  • log:/trunk/tools - the latest revisions in trunk/tools
  • log:/trunk/tools@10000 - the revisions in trunk/tools starting from revision 10000
  • log:@20788,20791:20795 - list revision 20788 and the 20791 to 20795 revision range
  • log:/trunk/tools@20788,20791:20795 - list revision 20788 and the revisions from the 20791 to 20795 range which affect the given path

There are short forms for revision ranges as well:

  • [20788,20791:20795]
  • [20788,20791:20795/trunk/tools]
  • r20791:20795 (but not r20788,20791:20795 nor r20791:20795/trunk)

Finally, note that in all of the above, a revision range can be written indifferently x:y or x-y.

See also: WikiFormatting, TracWiki, WikiPageNames, InterTrac, InterWiki