Sometimes it is useful to construct a working copy that is made out of a number of different checkouts. For example, you may want different files or subdirectories to come from different locations in a repository, or perhaps from different repositories altogether. If you want every user to have the same layout, you can define the svn:externals properties to pull in the specified resource at the locations where they are needed.
Let's say you check out a working copy of /project1 to D:\dev\project1. Select the folder D:\dev\project1, right click and choose → from the context menu. The Properties Dialog comes up. Then go to the Subversion tab. There, you can set properties. Click . In the properties dialog, either double click on the svn:externals if it already exists, or click on the button and select externals from the menu. To add a new external, click the and then fill in the required information in the shown dialog.
URLs must be properly escaped or they will not work, e.g. you must replace each space with %20.
If you want the local path to include spaces or other special characters, you can enclose it in double quotes, or you can use the \ (backslash) character as a Unix shell style escape character preceding any special character. Of course this also means that you must use / (forward slash) as a path delimiter. Note that this behaviour is new in Subversion 1.6 and will not work with older clients.
You should strongly consider using explicit revision numbers in all of your externals definitions, as described above. Doing so means that you get to decide when to pull down a different snapshot of external information, and exactly which snapshot to pull. Besides the common sense aspect of not being surprised by changes to third-party repositories that you might not have any control over, using explicit revision numbers also means that as you backdate your working copy to a previous revision, your externals definitions will also revert to the way they looked in that previous revision, which in turn means that the external working copies will be updated to match the way they looked back when your repository was at that previous revision. For software projects, this could be the difference between a successful and a failed build of an older snapshot of your complex code base.
The edit dialog for svn:externals properties allows you to select the externals and automatically set them explicitly to the HEAD revision.
If the external project is in the same repository, any changes you make there will be included in the commit list when you commit your main project.
If the external project is in a different repository, any changes you make to the external project will be shown or indicated when you commit the main project, but you have to commit those external changes separately.
Če uporabljate absolutne naslove URL v definicijah svn:externals in morate delovno kopijo premestiti (n. pr. če se spremeni naslov skladišča), se zunanji ne bodo spremenili in morda ne bodo več delovali.
V izogib tem težavam odjemalci Subversion verzije 1.5 ali novejše podpirajo relativne zunanje naslove URL. Na voljo so štirje načini podajanja relativnega naslova URL. V naslednjih primerih predpostavljamo, da imamo dve skladišči: enega na naslovu http://primer.com/svn/sklad-1 in drugega na naslovu http://primer.com/svn/sklad-2. Prevzem naslova http://primer.com/svn/sklad-1/projekt/trunk naredimo v mapo C:\Delo, lastnost svn:externals pa je nastavljena na glavno vejo (trunk).
These URLs always begin with the string ../ for example:
../../widgets/foo common/foo-widget
This will extract http://example.com/svn/repos-1/widgets/foo into C:\Working\common\foo-widget.
Upoštevajte, da je naslov URL relativen na naslov URL mape, ki ima nastavljeno lastnost svn:externals in ne na mapo, kjer se zunanji elementi nahajajo.
These URLs always begin with the string ^/ for example:
^/widgets/foo common/foo-widget
This will extract http://example.com/svn/repos-1/widgets/foo into C:\Working\common\foo-widget.
You can easily refer to other repositories with the same SVNParentPath (a common directory holding several repositories). For example:
^/../repos-2/hammers/claw common/claw-hammer
This will extract http://example.com/svn/repos-2/hammers/claw into C:\Working\common\claw-hammer.
URLs beginning with the string // copy only the scheme part of the URL. This is useful when the same hostname must the accessed with different schemes depending upon network location; e.g. clients in the intranet use http:// while external clients use svn+ssh://. For example:
//example.com/svn/repos-1/widgets/foo common/foo-widget
This will extract http://example.com/svn/repos-1/widgets/foo or svn+ssh://example.com/svn/repos-1/widgets/foo depending on which method was used to checkout C:\Working.
URLs beginning with the string / copy the scheme and the hostname part of the URL, for example:
/svn/repos-1/widgets/foo common/foo-widget
This will extract http://example.com/svn/repos-1/widgets/foo into C:\Working\common\foo-widget. But if you checkout your working copy from another server at svn+ssh://another.mirror.net/svn/repos-1/project1/trunk then the external reference will extract svn+ssh://another.mirror.net/svn/repos-1/widgets/foo.
You can also specify a peg and operative revision for the URL if required. To learn more about peg and operative revisions, please read the corresponding chapter in the Subversion book.
If you specify the target folder for the external as a subfolder like in the examples above, make sure that all folders in between are versioned as well. So for the examples above, the folder common should be versioned!
While the external will work in most situations properly if folders in between are not versioned, there are some operations that won't work as you expect. And the status overlay icons in explorer will also not show the correct status.
Če želite izvedeti več o tem, kako Subversion obravnava lastnosti, preberite “Nastavitve projekta”.
Za pregled različnih načinov dostopa do skupnih projektov si preberite “Kako vključim skupni podprojekt”.
As of Subversion 1.6 you can add single file externals to your working copy using the same syntax as for folders. However, there are some restrictions.
The path to the file external must be a direct child of the folder where you set the svn:externals property.
The URL for a file external must be in the same repository as the URL that the file external will be inserted into; inter-repository file externals are not supported.
A file external behaves just like any other versioned file in many respects, but they cannot be moved or deleted using the normal commands; the svn:externals property must be modified instead.
If you already have a working copy of the files or folders you want to include as externals in another working copy, you can simply add those via drag and drop from the windows explorer.
Simply right drag the file or folder from one working copy to where you want those to be included as externals. A context menu appears when you release the mouse button: if you click on that context menu entry, the svn:externals property is automatically added. All you have to do after that is commit the property changes and update to get those externals properly included in your working copy.