Управление версиями в Subversion Для Subversion 3 (в редакции 2345) Бен Коллинз-Сассман
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- Бұл бет үшін навигация:
- Basic Apache Configuration
- Basic HTTP Authentication
- SSL Certificate Management
- Per-Directory Access Control
- Disabling Path-based Checks
httpd, the Apache HTTP serverThe Apache HTTP Server is a «heavy duty» network server that Subversion can leverage. Via a custom module, httpd makes Subversion repositories available to clients via the WebDAV/DeltaV protocol, which is an extension to HTTP 1.1 (see http://www.webdav.org/ for more information). This protocol takes the ubiquitous HTTP protocol that is the core of the World Wide Web, and adds writing—specifically, versioned writing—capabilities. The result is a standardized, robust system that is conveniently packaged as part of the Apache 2.0 software, is supported by numerous operating systems and third-party products, and doesn't require network administrators to open up yet another custom port. [30] While an Apache-Subversion server has more features than svnserve, it's also a bit more difficult to set up. With flexibility often comes more complexity. Much of the following discussion includes references to Apache configuration directives. While some examples are given of the use of these directives, describing them in full is outside the scope of this chapter. The Apache team maintains excellent documentation, publicly available on their website at http://httpd.apache.org. For example, a general reference for the configuration directives is located at http://httpd.apache.org/docs-2.0/mod/directives.html. Also, as you make changes to your Apache setup, it is likely that somewhere along the way a mistake will be made. If you are not already familiar with Apache's logging subsystem, you should become aware of it. In your httpd.conf file are directives that specify the on-disk locations of the access and error logs generated by Apache (the CustomLog and ErrorLog directives, respectively). Subversion's mod_dav_svn uses Apache's error logging interface as well. You can always browse the contents of those files for information that might reveal the source of a problem that is not clearly noticeable otherwise.
If you're a system administrator, it's very likely that you're already running the Apache web server and have some prior experience with it. At the time of writing, Apache 1.3 is by far the most popular version of Apache. The world has been somewhat slow to upgrade to the Apache 2.X series for various reasons: some people fear change, especially changing something as critical as a web server. Other people depend on plug-in modules that only work against the Apache 1.3 API, and are waiting for a 2.X port. Whatever the reason, many people begin to worry when they first discover that Subversion's Apache module is written specifically for the Apache 2 API. The proper response to this problem is: don't worry about it. It's easy to run Apache 1.3 and Apache 2 side-by-side; simply install them to separate places, and use Apache 2 as a dedicated Subversion server that runs on a port other than 80. Clients can access the repository by placing the port number into the URL: $ svn checkout http://host.example.com:7382/repos/project …
PrerequisitesTo network your repository over HTTP, you basically need four components, available in two packages. You'll need Apache httpd 2.0, the mod_dav DAV module that comes with it, Subversion, and the mod_dav_svn filesystem provider module distributed with Subversion. Once you have all of those components, the process of networking your repository is as simple as:
You can accomplish the first two items either by compiling httpd and Subversion from source code, or by installing pre-built binary packages of them on your system. For the most up-to-date information on how to compile Subversion for use with the Apache HTTP Server, as well as how to compile and configure Apache itself for this purpose, see the INSTALL file in the top level of the Subversion source code tree. Basic Apache ConfigurationOnce you have all the necessary components installed on your system, all that remains is the configuration of Apache via its httpd.conf file. Instruct Apache to load the mod_dav_svn module using the LoadModule directive. This directive must precede any other Subversion-related configuration items. If your Apache was installed using the default layout, your mod_dav_svn module should have been installed in the modules subdirectory of the Apache install location (often /usr/local/apache2). The LoadModule directive has a simple syntax, mapping a named module to the location of a shared library on disk: LoadModule dav_svn_module modules/mod_dav_svn.so Note that if mod_dav was compiled as a shared object (instead of statically linked directly to the httpd binary), you'll need a similar LoadModule statement for it, too. Be sure that it comes before the mod_dav_svn line: LoadModule dav_module modules/mod_dav.so LoadModule dav_svn_module modules/mod_dav_svn.so At a later location in your configuration file, you now need to tell Apache where you keep your Subversion repository (or repositories). The Location directive has an XML-like notation, starting with an opening tag, and ending with a closing tag, with various other configuration directives in the middle. The purpose of the Location directive is to instruct Apache to do something special when handling requests that are directed at a given URL or one of its children. In the case of Subversion, you want Apache to simply hand off support for URLs that point at versioned resources to the DAV layer. You can instruct Apache to delegate the handling of all URLs whose path portions (the part of the URL that follows the server's name and the optional port number) begin with /repos/ to a DAV provider whose repository is located at /absolute/path/to/repository using the following httpd.conf syntax: DAV svn
SVNPath /absolute/path/to/repository If you plan to support multiple Subversion repositories that will reside in the same parent directory on your local disk, you can use an alternative directive, the SVNParentPath directive, to indicate that common parent directory. For example, if you know you will be creating multiple Subversion repositories in a directory /usr/local/svn that would be accessed via URLs like http://my.server.com/svn/repos1, http://my.server.com/svn/repos2, and so on, you could use the httpd.conf configuration syntax in the following example: DAV svn
SVNParentPath /usr/local/svn
Using the previous syntax, Apache will delegate the handling of all URLs whose path portions begin with /svn/ to the Subversion DAV provider, which will then assume that any items in the directory specified by the SVNParentPath directive are actually Subversion repositories. This is a particularly convenient syntax in that, unlike the use of the SVNPath directive, you don't have to restart Apache in order to create and network new repositories. Be sure that when you define your new Location, it doesn't overlap with other exported Locations. For example, if your main DocumentRoot is /www, do not export a Subversion repository in Subversion makes use of the COPY request type to perform server-side copies of files and directories. As part of the sanity checking done by the Apache modules, the source of the copy is expected to be located on the same machine as the destination of the copy. To satisfy this requirement, you might need to tell mod_dav the name you use as the hostname of your server. Generally, you can use the ServerName directive in httpd.conf to accomplish this. ServerName svn.example.com If you are using Apache's virtual hosting support via the NameVirtualHost directive, you may need to use the ServerAlias directive to specify additional names that your server is known by. Again, refer to the Apache documentation for full details. At this stage, you should strongly consider the question of permissions. If you've been running Apache for some time now as your regular web server, you probably already have a collection of content—web pages, scripts and such. These items have already been configured with a set of permissions that allows them to work with Apache, or more appropriately, that allows Apache to work with those files. Apache, when used as a Subversion server, will also need the correct permissions to read and write to your Subversion repository. (See Servers and Permissions: A Word of Warning.) You will need to determine a permission system setup that satisfies Subversion's requirements without messing up any previously existing web page or script installations. This might mean changing the permissions on your Subversion repository to match those in use by other things that Apache serves for you, or it could mean using the User and Group directives in httpd.conf to specify that Apache should run as the user and group that owns your Subversion repository. There is no single correct way to set up your permissions, and each administrator will have different reasons for doing things a certain way. Just be aware that permission-related problems are perhaps the most common oversight when configuring a Subversion repository for use with Apache. Authentication OptionsAt this point, if you configured httpd.conf to contain something like DAV svn
SVNParentPath /usr/local/svn ...then your repository is «anonymously» accessible to the world. Until you configure some authentication and authorization policies, the Subversion repositories you make available via the Location directive will be generally accessible to everyone. In other words,
Basic HTTP AuthenticationThe easiest way to authenticate a client is via the HTTP Basic authentication mechanism, which simply uses a username and password to verify that a user is who she says she is. Apache provides an htpasswd utility for managing the list of acceptable usernames and passwords, those to whom you wish to grant special access to your Subversion repository. Let's grant commit access to Sally and Harry. First, we need to add them to the password file. $ ### First time: use -c to create the file $ ### Use -m to use MD5 encryption of the password, which is more secure $ htpasswd -cm /etc/svn-auth-file harry New password: ***** Re-type new password: ***** Adding password for user harry $ htpasswd -m /etc/svn-auth-file sally New password: ******* Re-type new password: ******* Adding password for user sally $ Next, you need to add some more httpd.conf directives inside your Location block to tell Apache what to do with your new password file. The AuthType directive specifies the type of authentication system to use. In this case, we want to specify the Basic authentication system. AuthName is an arbitrary name that you give for the authentication domain. Most browsers will display this name in the pop-up dialog box when the browser is querying the user for his name and password. Finally, use the AuthUserFile directive to specify the location of the password file you created using htpasswd. After adding these three directives, your DAV svn
SVNParentPath /usr/local/svn AuthType Basic AuthName "Subversion repository" AuthUserFile /etc/svn-auth-file This DAV svn
SVNParentPath /usr/local/svn AuthType Basic AuthName "Subversion repository" AuthUserFile /etc/svn-auth-file Require valid-user
Be sure to read the next section («Authorization Options») for more detail on the Require directive and other ways to set authorization policies. One word of warning: HTTP Basic Auth passwords pass in very nearly plain-text over the network, and thus are extremely insecure. If you're worried about password snooping, it may be best to use some sort of SSL encryption, so that clients authenticate via https:// instead of http://; at a bare minimum, you can configure Apache to use a self-signed server certificate. [31] Consult Apache's documentation (and OpenSSL documentation) about how to do that.
If a Subversion client is compiled to use OpenSSL, then it gains the ability to speak to an Apache server via https:// URLs. The Neon library used by the Subversion client is not only able to verify server certificates, but can also supply client certificates when challenged. When the client and server have exchanged SSL certificates and successfully authenticated one another, all further communication is encrypted via a session key. It's beyond the scope of this book to describe how to generate client and server certificates, and how to configure Apache to use them. Many other books, including Apache's own documentation, describe this task. But what can be covered here is how to manage server and client certificates from an ordinary Subversion client. When speaking to Apache via https://, a Subversion client can receive two different types of information:
If the client receives a server certificate, it needs to verify that it trusts the certificate: is the server really who it claims to be? The OpenSSL library does this by examining the signer of the server certificate, or certifying authority (CA). If OpenSSL is unable to automatically trust the CA, or if some other problem occurs (such as an expired certificate or hostname mismatch), the Subversion command-line client will ask you whether you want to trust the server certificate anyway: $ svn list https://host.example.com/repos/project Error validating server certificate for 'https://host.example.com:443': - The certificate is not issued by a trusted authority. Use the fingerprint to validate the certificate manually! Certificate information: - Hostname: host.example.com - Valid: from Jan 30 19:23:56 2004 GMT until Jan 30 19:23:56 2006 GMT - Issuer: CA, example.com, Sometown, California, US - Fingerprint: 7d:e1:a9:34:33:39:ba:6a:e9:a5:c4:22:98:7b:76:5c:92:a0:9c:7b (R)eject, accept (t)emporarily or accept (p)ermanently? This dialogue should look familiar; it's essentially the same question you've probably seen coming from your web browser (which is just another HTTP client like Subversion!). If you choose the (p)ermanent option, the server certificate will be cached in your private run-time auth/ area in just the same way your username and password are cached (see «Кеширование клиентской идентификационной информации»). If cached, Subversion will automatically remember to trust this certificate in future negotiations. Your run-time servers file also gives you the ability to make your Subversion client automatically trust specific CAs, either globally or on a per-host basis. Simply set the ssl-authority-files variable to a semicolon-separated list of PEM-encoded CA certificates: [global]
ssl-authority-files = /path/to/CAcert1.pem;/path/to/CAcert2.pem Many OpenSSL installations also have a pre-defined set of «default» CAs that are nearly universally trusted. To make the Subversion client automatically trust these standard authorities, set the ssl-trust-default-ca variable to true. When talking to Apache, a Subversion client might also receive a challenge for a client certificate. Apache is asking the client to identify itself: is the client really who it says it is? If all goes correctly, the Subversion client sends back a private certificate signed by a CA that Apache trusts. A client certificate is usually stored on disk in encrypted format, protected by a local password. When Subversion receives this challenge, it will ask you for both a path to the certificate and the password which protects it: $ svn list https://host.example.com/repos/project Authentication realm: https://host.example.com:443 Client certificate filename: /path/to/my/cert.p12 Passphrase for '/path/to/my/cert.p12': ******** … Notice that the client certificate is a «p12» file. To use a client certificate with Subversion, it must be in PKCS#12 format, which is a portable standard. Most web browsers are already able to import and export certificates in that format. Another option is to use the OpenSSL command-line tools to convert existing certificates into PKCS#12. Again, the runtime servers file allows you to automate this challenge on a per-host basis. Either or both pieces of information can be described in runtime variables: [groups]
examplehost = host.example.com [examplehost] ssl-client-cert-file = /path/to/my/cert.p12 ssl-client-cert-password = somepassword Once you've set the ssl-client-cert-file and ssl-client-cert-password variables, the Subversion client can automatically respond to a client certificate challenge without prompting you. [32] Authorization OptionsAt this point, you've configured authentication, but not authorization. Apache is able to challenge clients and confirm identities, but it has not been told how to allow or restrict access to the clients bearing those identities. This section describes two strategies for controlling access to your repositories. Blanket Access ControlThe simplest form of access control is to authorize certain users for either read-only access to a repository, or read/write access to a repository. You can restrict access on all repository operations by adding the Require valid-user directive to your DAV svn
SVNParentPath /usr/local/svn # how to authenticate a user AuthType Basic AuthName "Subversion repository" AuthUserFile /path/to/users/file # only authenticated users may access the repository Require valid-user Sometimes you don't need to run such a tight ship. For example, Subversion's own source code repository at http://svn.collab.net/repos/svn allows anyone in the world to perform read-only repository tasks (like checking out working copies and browsing the repository with a web browser), but restricts all write operations to authenticated users. To do this type of selective restriction, you can use the Limit and LimitExcept configuration directives. Like the Location directive, these blocks have starting and ending tags, and you would nest them inside your The parameters present on the Limit and LimitExcept directives are HTTP request types that are affected by that block. For example, if you wanted to disallow all access to your repository except the currently supported read-only operations, you would use the LimitExcept directive, passing the GET, PROPFIND, OPTIONS, and REPORT request type parameters. Then the previously mentioned Require valid-user directive would be placed inside the DAV svn
SVNParentPath /usr/local/svn # how to authenticate a user AuthType Basic AuthName "Subversion repository" AuthUserFile /path/to/users/file # For any operations other than these, require an authenticated user. Require valid-user These are only a few simple examples. For more in-depth information about Apache access control and the Require directive, take a look at the Security section of the Apache documentation's tutorials collection at http://httpd.apache.org/docs-2.0/misc/tutorials.html. Per-Directory Access ControlIt's possible to set up finer-grained permissions using a second Apache httpd module, mod_authz_svn. This module grabs the various opaque URLs passing from client to server, asks mod_dav_svn to decode them, and then possibly vetoes requests based on access policies defined in a configuration file. If you've built Subversion from source code, mod_authz_svn is automatically built and installed alongside mod_dav_svn. Many binary distributions install it automatically as well. To verify that it's installed correctly, make sure it comes right after mod_dav_svn's LoadModule directive in httpd.conf: LoadModule dav_module modules/mod_dav.so LoadModule dav_svn_module modules/mod_dav_svn.so LoadModule authz_svn_module modules/mod_authz_svn.so To activate this module, you need to configure your Location block to use the AuthzSVNAccessFile directive, which specifies a file containing the permissions policy for paths within your repositories. (In a moment, we'll discuss the format of that file.) Apache is flexible, so you have the option to configure your block in one of three general patterns. To begin, choose one of these basic configuration patterns. (The examples below are very simple; look at Apache's own documentation for much more detail on Apache authentication and authorization options.) The simplest block is to allow open access to everyone. In this scenario, Apache never sends authentication challenges, so all users are treated as «anonymous». Пример 6.1. A sample configuration for anonymous access. DAV svn
SVNParentPath /usr/local/svn # our access control policy AuthzSVNAccessFile /path/to/access/file On the opposite end of the paranoia scale, you can configure your block to demand authentication from everyone. All clients must supply credentials to identify themselves. Your block unconditionally requires authentication via the Require valid-user directive, and defines a means to authenticate. Пример 6.2. A sample configuration for authenticated access. DAV svn
SVNParentPath /usr/local/svn # our access control policy AuthzSVNAccessFile /path/to/access/file # only authenticated users may access the repository Require valid-user # how to authenticate a user AuthType Basic AuthName "Subversion repository" AuthUserFile /path/to/users/file A third very popular pattern is to allow a combination of authenticated and anonymous access. For example, many administrators want to allow anonymous users to read certain repository directories, but want only authenticated users to read (or write) more sensitive areas. In this setup, all users start out accessing the repository anonymously. If your access control policy demands a real username at any point, Apache will demand authentication from the client. To do this, you use both the Satisfy Any and Require valid-user directives together. Пример 6.3. A sample configuration for mixed authenticated/anonymous access. DAV svn
SVNParentPath /usr/local/svn # our access control policy AuthzSVNAccessFile /path/to/access/file # try anonymous access first, resort to real # authentication if necessary. Satisfy Any Require valid-user # how to authenticate a user AuthType Basic AuthName "Subversion repository" AuthUserFile /path/to/users/file Once your basic Location block is configured, you can create an access file and define some authorization rules in it. The syntax of the access file is the same familiar one used by svnserve.conf and the runtime configuration files. Lines that start with a hash (#) are ignored. In its simplest form, each section names a repository and path within it, and the authenticated usernames are the option names within each section. The value of each option describes the user's level of access to the repository path: either r (read-only) or rw (read-write). If the user is not mentioned at all, no access is allowed. To be more specific: the value of the section-names are either of the form [repos-name:path] or the form [path]. If you're using the SVNParentPath directive, then it's important to specify the repository names in your sections. If you omit them, then a section like [/some/dir] will match the path /some/dir in every repository. If you're using the SVNPath directive, however, then it's fine to only define paths in your sections—after all, there's only one repository. [calc:/branches/calc/bug-142] harry = rw sally = r In this first example, the user harry has full read and write access on the /branches/calc/bug-142 directory in the calc repository, but the user sally has read-only access. Any other users are blocked from accessing this directory. Of course, permissions are inherited from parent to child directory. That means that we can specify a subdirectory with a different access policy for Sally: [calc:/branches/calc/bug-142] harry = rw sally = r # give sally write access only to the 'testing' subdir [calc:/branches/calc/bug-142/testing] sally = rw Now Sally can write to the testing subdirectory of the branch, but can still only read other parts. Harry, meanwhile, continues to have complete read-write access to the whole branch. It's also possible to explicitly deny permission to someone via inheritance rules, by setting the username variable to nothing: [calc:/branches/calc/bug-142] harry = rw sally = r [calc:/branches/calc/bug-142/secret] harry =
In this example, Harry has read-write access to the entire bug-142 tree, but has absolutely no access at all to the secret subdirectory within it. The thing to remember is that the most specific path always matches first. The mod_authz_svn module tries to match the path itself, and then the parent of the path, then the parent of that, and so on. The net effect is that mentioning a specific path in the accessfile will always override any permissions inherited from parent directories. By default, nobody has any access to the repository at all. That means that if you're starting with an empty file, you'll probably want to give at least read permission to all users at the root of the repository. You can do this by using the asterisk variable (*), which means «all users»: [/]
* = r This is a common setup; notice that there's no repository name mentioned in the section name. This makes all repositories world readable to all users, whether you're using SVNPath or SVNParentPath. Once all users have read-access to the repositories, you can give explicit rw permission to certain users on specific subdirectories within specific repositories. The asterisk variable (*) is also worth special mention here: it's the only pattern which matches an anonymous user. If you've configured your Location block to allow a mixture of anonymous and authenticated access, all users start out accessing Apache anonymously. mod_authz_svn looks for a * value defined for the path being accessed; if it can't find one, then Apache demands real authentication from the client. The access file also allows you to define whole groups of users, much like the Unix /etc/group file: [groups] calc-developers = harry, sally, joe paint-developers = frank, sally, jane everyone = harry, sally, joe, frank, sally, jane Groups can be granted access control just like users. Distinguish them with an «at» (@) prefix: [calc:/projects/calc] @calc-developers = rw
@paint-developers = rw jane = r Groups can also be defined to contain other groups: [groups] calc-developers = harry, sally, joe paint-developers = frank, sally, jane everyone = @calc-developers, @paint-developers ...and that's pretty much all there is to it.
All of this path-checking can sometimes be quite expensive, especially in the case of svn log. When retrieving a list revisions, the server looks at every changed path in each revision and checks it for readability. If an unreadable path is discovered, then it's omitted from the list of the revision's changed paths (normally seen with the --verbose option), and the whole log message is suppressed. Needless to say, this can be time-consuming on revisions that affect a large number of files. This is the cost of security: even if you haven't configured a module like mod_authz_svn at all, the mod_dav_svn module is still asking Apache httpd to run authorization checks on every path. The mod_dav_svn module has no idea what authorization modules have been installed, so all it can do is ask Apache to invoke whatever might be present. On the other hand, there's also an escape-hatch of sorts, one which allows you to trade security features for speed. If you're not enforcing any sort of per-directory authorization (i.e. not using mod_authz_svn or similar module), then you can disable all of this path-checking. In your httpd.conf file, use the SVNPathAuthz directive:
DAV svn
SVNParentPath /usr/local/svn SVNPathAuthz off The SVNPathAuthz directive is «on» by default. When set «off», all path-based authorization checking is disabled; mod_dav_svn stops invoking authorization checks on every path it discovers. Extra GoodiesWe've covered most of the authentication and authorization options for Apache and mod_dav_svn. But there are a few other nice features that Apache provides. Repository BrowsingOne of the most useful benefits of an Apache/WebDAV configuration for your Subversion repository is that the youngest revisions of your versioned files and directories are immediately available for viewing via a regular web browser. Since Subversion uses URLs to identify versioned resources, those URLs used for HTTP-based repository access can be typed directly into a Web browser. Your browser will issue a GET request for that URL, and based on whether that URL represents a versioned directory or file, mod_dav_svn will respond with a directory listing or with file contents. Since the URLs do not contain any information about which version of the resource you wish to see, mod_dav_svn will always answer with the youngest version. This functionality has the wonderful side-effect that you can pass around Subversion URLs to your peers as references to documents, and those URLs will always point at the latest manifestation of that document. Of course, you can even use the URLs as hyperlinks from other web sites, too. You generally will get more use out of URLs to versioned files—after all, that's where the interesting content tends to lie. But you might have occasion to browse a Subversion directory listing, where you'll quickly note that the generated HTML used to display that listing is very basic, and certainly not intended to be aesthetically pleasing (or even interesting). To enable customization of these directory displays, Subversion provides an XML index feature. A single SVNIndexXSLT directive in your repository's Location block of httpd.conf will instruct mod_dav_svn to generate XML output when displaying a directory listing, and to reference the XSLT stylesheet of your choice:
DAV svn
SVNParentPath /usr/local/svn SVNIndexXSLT "/svnindex.xsl" …
Using the SVNIndexXSLT directive and a creative XSLT stylesheet, you can make your directory listings match the color schemes and imagery used in other parts of your website. Or, if you'd prefer, you can use the sample stylesheets provided in the Subversion source distribution's tools/xslt/ directory. Keep in mind that the path provided to the SVNIndexXSLT directory is actually a URL path—browsers need to be able to read your stylesheets in order to make use of them! Can I view older revisions? With an ordinary web browser? In one word: nope. At least, not with mod_dav_svn as your only tool. Your web browser only speaks ordinary HTTP. That means it only knows how to GET public URLs, which represent the latest versions of files and directories. According to the WebDAV/DeltaV spec, each server defines a private URL syntax for older versions of resources, and that syntax is opaque to clients. To find an older version of a file, a client must follow a specific procedure to «discover» the proper URL; the procedure involves issuing a series of WebDAV PROPFIND requests and understanding DeltaV concepts. This is something your web browser simply can't do. So to answer the question, one obvious way to see older revisions of files and directories is by passing the --revision argument to the svn list and svn cat commands. To browse old revisions with your web browser, however, you can use third-party software. A good example of this is ViewVC (http://viewvc.tigris.org/). ViewVC was originally written to display CVS repositories through the web, [33] and the latest bleeding-edge versions (at the time of writing) are able to understand Subversion repositories as well. Other FeaturesSeveral of the features already provided by Apache in its role as a robust Web server can be leveraged for increased functionality or security in Subversion as well. Subversion communicates with Apache using Neon, which is a generic HTTP/WebDAV library with support for such mechanisms as SSL (the Secure Socket Layer, discussed earlier) and Deflate compression (the same algorithm used by the gzip and PKZIP programs to «shrink» files into smaller chunks of data). You need only to compile support for the features you desire into Subversion and Apache, and properly configure the programs to use those features. Deflate compression places a small burden on the client and server to compress and decompress network transmissions as a way to minimize the size of the actual transmission. In cases where network bandwidth is in short supply, this kind of compression can greatly increase the speed at which communications between server and client can be sent. In extreme cases, this minimized network transmission could be the difference between an operation timing out or completing successfully. Less interesting, but equally useful, are other features of the Apache and Subversion relationship, such as the ability to specify a custom port (instead of the default HTTP port 80) or a virtual domain name by which the Subversion repository should be accessed, or the ability to access the repository through a proxy. These things are all supported by Neon, so Subversion gets that support for free. Finally, because mod_dav_svn is speaking a semi-complete dialect of WebDAV/DeltaV, it's possible to access the repository via third-party DAV clients. Most modern operating systems (Win32, OS X, and Linux) have the built-in ability to mount a DAV server as a standard network «share». This is a complicated topic; for details, read Приложение B, WebDAV и автоматическое управление версиями. жүктеу/скачать 2.13 Mb. Достарыңызбен бөлісу:
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