[svnbook commit] r1678 - trunk/src/zh/book
rocksun
svnbook-dev at red-bean.com
Sat Sep 10 08:46:51 CDT 2005
Author: rocksun
Date: Sat Sep 10 08:46:50 2005
New Revision: 1678
Modified:
trunk/src/zh/book/appc.xml
Log:
* zh/book/appc.xml: Add UTF BOM, finished.
Modified: trunk/src/zh/book/appc.xml
==============================================================================
--- trunk/src/zh/book/appc.xml (original)
+++ trunk/src/zh/book/appc.xml Sat Sep 10 08:46:50 2005
@@ -1,110 +1,65 @@
-<appendix id="svn-ap-c">
-<title>WebDAV and Autoversioning</title>
+<appendix id="svn-ap-c">
+<title>WebDAV和自动版本化</title>
<simplesect>
- <para>WebDAV is an extension to HTTP, and is growing more and more
- popular as a standard for file-sharing. Today's operating
- systems are becoming extremely Web-aware, and many have now
- built-in support for mounting <quote>shares</quote> exported by
- WebDAV servers.</para>
-
- <para>If you use Apache/mod_dav_svn as your Subversion network
- server, then to some extent, you are also running a WebDAV
- server. This appendix gives some background on the nature of
- this protocol, how Subversion uses it, and how well Subversion
- interoperates with other software that is WebDAV-aware.</para>
+ <para>WebDAV是HTTP的一个扩展，作为一个文件共享的标准不断发展。当今的操作系统变得极端的web化，许多内置了对装配WebDAV服务器导出的<quote>共享</quote>的支持。
+ </para>
+
+ <para>如果你使用Apache/mod_dav_svn作为你的Subversion网络服务器，某种程度上，你也是在运行一个WebDAV服务器。这个附录提供了这种协议一些背景知识，Subversion如何使用它，Subversion如何和认识WebDAV的软件交互工作。
+ </para>
</simplesect>
<sect1 id="svn-ap-c-sect-1">
- <title>Basic WebDAV Concepts</title>
+ <title>WebDAV基本概念</title>
- <para>This section provides a very brief, very general overview to
- the ideas behind WebDAV. It should lay the foundation for
- understanding WebDAV compatibility issues between clients and
- servers.</para>
+ <para>这个小节提供了对WebDAV背后思想的一个非常简短和普通的总体看法，为理解WebDAV在客户端和服务器之间的兼容性问题打下基础。
+ </para>
<sect2 id="svn-ap-c-sect-1.1">
- <title>Just Plain WebDAV</title>
+ <title>仅是平常的WebDAV</title>
- <para>RFC 2518 defines a set of concepts and accompanying
- extension methods to HTTP 1.1 that make the web into a more
- universal read/write medium. The basic idea is that a
- WebDAV-compliant web server can act like a generic file server;
- clients can mount WebDAV <quote>shares</quote> that behave
- much like NFS or SMB shares.</para>
+ <para>RFC 2518为HTTP 1.1定义了一组概念和附加扩展方法来把web变成一个更加普遍的读/写媒体，基本思想是一个WebDAV兼容的web服务器可以像普通的文件服务器一样工作；客户端可以装配类似于NFS或SMB的WebDAV<quote>共享</quote>。
+ </para>
- <para>However, it's important to note that RFC 2518 does
- <emphasis>not</emphasis> provide any sort of model for version
- control, despite the <quote>V</quote> in DAV. Basic WebDAV
- clients and servers assume only one version of each file or
- directory exists, and can be repeatedly overwritten.
- <footnote><para>For this reason, some people jokingly refer to
- generic WebDAV clients as <quote>WebDA</quote>
- clients!</para></footnote></para>
+ <para>然而，必须注意到RFC 2518并<emphasis>没有</emphasis>提供任何版本控制模型，尽管DAV中有<quote>V</quote>。基本的DAV客户端和服务器只是假定每个文件或目录只有一个版本存在，可以重复的覆盖。<footnote><para>因为这个原因，一些人开玩笑说WebDAV的客户端是<quote>WebDA</quote>客户端！
+ </para></footnote></para>
- <para>Here are the new concepts and methods introduced in basic
- WebDAV:</para>
+ <para>这是基本的WebDAV引入的新概念和方法：
+ </para>
<variablelist>
<varlistentry>
- <term>New write methods</term>
+ <term>新的写方法</term>
<listitem>
- <para>Beyond the standard HTTP <literal>PUT</literal>
- method (which creates or overwrites a web resource),
- WebDAV defines new <literal>COPY</literal> and
- <literal>MOVE</literal> methods for duplicating or
- rearranging resources.</para>
+ <para>超出了标准HTTP的<literal>PUT</literal>方法（用来创建和覆盖web资源），WebDAV定义了新的<literal>COPY</literal>和<literal>MOVE</literal>方法用来复制或重新组织资源。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Collections</term>
+ <term>集合</term>
<listitem>
- <para>This is simply the WebDAV term for a grouping of
- resources (URIs). In most cases, it is analogous to a
- <quote>directory</quote>. You can tell something is a
- collection if it ends with a trailing <quote>/</quote>.
- Whereas file resources can be written or created with a
- <literal>PUT</literal> method, collection resources are
- created with the new <literal>MKCOL</literal>
- method.</para>
+ <para>这是一个简单的WebDAV术语用来表示一组资源（URI），在大多数情况下，你可以说以<quote>/</quote>结尾的东西是一个集合，文件资源可以使用<literal>PUT</literal>方法写或创建，而集合资源使用<literal>MKCOL</literal>方法创建。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Properties</term>
- <listitem>
- <para>This is the same idea present in
- Subversion—metadata attached to files and
- collections. A client can list or retrieve properties
- attached to a resource with the new
- <literal>PROPFIND</literal> method, and can change them
- with the <literal>PROPPATCH</literal> method. Some
- properties are wholly created and controlled by users
- (e.g. a property called <quote>color</quote>), and
- others are wholly created and controlled by the WebDAV
- server (e.g. a property that contains the last
- modification time of a file). The former kind are
- called <quote>dead</quote> properties, and the latter
- kind are called <quote>live</quote> properties.</para>
+ <term>属性</term>
+ <listitem>
+ <para>这与Subversion中的是同一个思想—附加在文件和集合上的元数据，一个客户端可以使用新方法<literal>PROPFIND</literal>列出或检索附加在一个资源上的属性，也可以使用<literal>PROPPATCH</literal>方法修改这些属性。一些属性是完全由用户控制的（例如，一个<quote>color</quote>属性），还有一些是WebDAV服务器创建和控制的（例如，一个保存文件最后修改时间的属性）。前一种叫做<quote>dead</quote>属性，后一种叫做<quote>live</quote>属性。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Locking</term>
+ <term>锁定</term>
<listitem>
- <para>A WebDAV server may decide to offer a locking
- feature to clients—this part of the specification
- is optional, although most WebDAV servers do offer the
- feature. If present, then clients can use the new
- <literal>LOCK</literal> and <literal>UNLOCK</literal>
- methods to mediate access to a resource. In most cases
- these methods are used to create exclusive write locks
- (as discussed in <xref linkend="svn-ch-2-sect-2.2"/>),
- although shared write locks are also possible.</para>
+ <para>WebDAV服务器可以决定为客户端提供一个锁定特性—这部分的规范是可选的，尽管大多数WebDAV服务器提供了这个特性。如果提供这个特性，客户端可以使用新的<literal>LOCK</literal>和<literal>UNLOCK</literal>方法来调节访问资源的过程，在大多数情况下是使用独占写锁（在<xref linkend="svn-ch-2-sect-2.2"/>讨论的），尽管共享写锁也是可以的。
+ </para>
</listitem>
</varlistentry>
@@ -113,125 +68,61 @@
</sect2>
<sect2 id="svn-ap-c-sect-1.2">
- <title>DeltaV Extensions</title>
+ <title>DeltaV扩展</title>
- <para>Because RFC 2518 left out versioning concepts, another
- capable group was left with the responsibility of writing RFC
- 3253, which adds versioning to WebDAV. WebDAV/DeltaV clients
- and servers are often called just <quote>DeltaV</quote>
- clients and servers, since DeltaV implies the existence of
- basic WebDAV.</para>
-
- <para>DeltaV introduces a whole slew of new acronyms, but don't
- be intimidated. The ideas are fairly straightforward. Here
- are the new concepts and methods introduced in DeltaV:</para>
+ <para>因为RFC 2518漏下了版本概念，另一个小组留下来负责撰写RFC 3253来添加WebDAV的版本化。WebDAV/DeltaV客户端和服务器经常叫做<quote>DeltaV</quote>客户端和服务器，因为DeltaV暗含了基本的WebDAV。
+ </para>
+
+ <para>DeltaV引入了完全的新的首字母缩写，但并不是被逼迫的。想法相当的直接，如下是DeltaV引入的新概念和方法：
+ </para>
<variablelist>
<varlistentry>
- <term>Per-resource versioning</term>
+ <term>每资源的版本化</term>
<listitem>
- <para>Like CVS and other version-control systems, DeltaV
- assumes that each resource has a potentially infinite
- number of states. A client begins by placing a resource
- under version control using the new
- <literal>VERSION-CONTROL</literal> method. This creates
- a new Version Controlled Resource (VCR). Every time you
- change the VCR (via <literal>PUT</literal>,
- <literal>PROPPATCH</literal>, etc.), a new state of the
- resource is created, called a Version Resource (VR).
- VCRs and VRs are still ordinary web resources, defined
- by URLs. Specific VRs can have human-friendly names as
- well.</para>
+ <para>像CVS和其他版本控制系统，DeltaV假定每个资源有一个潜在的无穷的状态，一个客户端可以使用<literal>VERSION-CONTROL</literal>放置一个版本控制之下的资源，这创建了一个新的版本控制资源（VCR），每次你修改VCR（通过<literal>PUT</literal>、<literal>PROPPATCH</literal>等），这个资源的新状态就会创建，叫做一个版本资源（Version Resource，VR）。VCR和VR还是普通的web资源，使用URL定义，特定的VR也会拥有易读的名字。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Server-side working-copy model</term>
+ <term>服务器端的工作拷贝模型</term>
<listitem>
- <para>Some DeltaV servers support the ability to create a
- virtual <quote>workspace</quote> on the server, where
- all of your work is performed. Clients use the
- <literal>MKWORKSPACE</literal> method to create a
- private area, then indicate they want to change specific
- VCRs by <quote>checking them out</quote> into the
- workspace, editing them, and <quote>checking them
- in</quote> again. In HTTP terms, the sequence of
- methods would be <literal>CHECKOUT</literal>,
- <literal>PUT</literal>, <literal>CHECKIN</literal>.
- After each <literal>CHECKIN</literal>, a new VR is
- created, and the edited VCR's contents now <quote>point
- to</quote> the latest VR. Each VCR has also has a
- <quote>history</quote> resource which tracks and orders
- its various VR states.</para>
+ <para>一些DeltaV服务器支持在服务器创建虚拟<quote>工作区</quote>，所有的工作在这里执行。客户端使用<literal>MKWORKSPACE</literal>方法来创建私有区域，然后他们说明修改特定的VCR，<quote>把它们检出到</quote>工作拷贝，编辑，然后再次<quote>检入</quote>。在HTTP术语里，方法的顺序可能是<literal>CHECKOUT</literal>、<literal>PUT</literal>、<literal>CHECKIN</literal>，会创建一个新的VR，每个VCR也有一个<quote>历史</quote>资源用来追踪和排序它的各种VR状态。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Client-side working-copy model</term>
+ <term>客户端工作拷贝模型</term>
<listitem>
- <para>Some DeltaV servers also support the idea that the
- client may have a private working copy full of
- specific VRs. (This is how CVS and Subversion work.)
- When the client wants to commit changes to the server,
- it begins by creating a temporary server transaction
- (called an activity) with the
- <literal>MKACTIVITY</literal> method. The client then
- performs a <literal>CHECKOUT</literal> on each VR it
- wishes to change, which creates a number of temporary
- <quote>working resources</quote> in the activity, that
- can be modified using <literal>PUT</literal> and
- <literal>PROPPATCH</literal> methods. Finally, the
- client performs a <literal>CHECKIN</literal> on each
- working resource, which creates a new VR within each
- VCR, and the entire activity is deleted.</para>
+ <para>一些DeltaV服务器也支持客户端可以有完全特定VR的私有工作拷贝的思想，（这就是CVS和Subversion的工作原理。）当客户端希望提交修改到服务器，它通过使用<literal>MKACTIVITY</literal>方法创建一个临时服务器事务（叫做一个活动）开始。然后客户端在每个希望修改的VR上执行一个<literal>CHECKOUT</literal>操作，这在活动里创建了一些临时<quote>工作资源</quote>，然后可以使用<literal>PUT</literal>和<literal>PROPPATCH</literal>方法修改。最后，客户端对每个工作资源执行一个<literal>CHECKIN</literal>，在每个VCR创建了一个VR，并且整个活动会被删除。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Configurations</term>
+ <term>配置</term>
<listitem>
- <para>DeltaV allows you define flexible collections of
- VCRs called <quote>configurations</quote>, which don't
- necessarily correspond to particular directories. Each VCR's
- contents can be made to point to a specific VR using the
- <literal>UPDATE</literal> method. Once the configuration
- is perfect, the client can create a
- <quote>snapshot</quote> of the whole configuration, called
- a <quote>baseline</quote>. Clients use the
- <literal>CHECKOUT</literal> and <literal>CHECKIN</literal>
- methods to capture specific states of configurations, much
- like they use these methods to create specific VR states
- of VCRs.</para>
+ <para>DeltaV允许你定义叫做<quote>配置</quote>的灵活的VCR集合，不需要对应特定的目录，每个VCR的内容可以使用<literal>UPDATE</literal>方法指向特定的VR。一旦配置是理想的，客户端可以创建一个整个配置的<quote>快照</quote>，叫做<quote>基线</quote>。客户端使用<literal>CHECKOUT</literal>和<literal>CHECKIN</literal>方法捕捉特定的配置状态，很像它们使用这些方法创建VCR的特定VR状态。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Extensibility</term>
+ <term>扩展性</term>
<listitem>
- <para>DeltaV defines a new method,
- <literal>REPORT</literal>, which allows the client and
- server to perform customized data exchanges. The client
- sends a <literal>REPORT</literal> request with a
- properly-labeled XML body full of custom data; assuming
- the server understands the specific report-type, it
- responds with an equally custom XML body. This technique
- is very similar to XML-RPC.</para>
+ <para>DeltaV定义了新方法<literal>REPORT</literal>，允许客户端和服务器执行自定义的数据交换。客户端发送一个带有包含自定义数据的完全标记的XML主体的<literal>REPORT</literal>请求；假定服务器理解特定的报告类型，它使用一个等同的XML主体来响应，这个技术与XML-RPC很类似。
+ </para>
</listitem>
</varlistentry>
<varlistentry>
- <term>Autoversioning</term>
+ <term>自动版本化</term>
<listitem>
- <para>For many, this is the <quote>killer</quote> feature
- of DeltaV. If the DeltaV server supports this feature,
- then basic WebDAV clients (i.e. those unaware of
- versioning) can still write to the server, and the server
- will silently perform versioning anyway. In the simplest
- example, an ignorant <literal>PUT</literal> from a basic
- WebDAV client might be translated by the server as a
- <literal>CHECKOUT</literal>, <literal>PUT</literal>,
- <literal>CHECKIN</literal>.</para>
+ <para>对大多数，这是DeltaV的<quote>杀手</quote>特性，如果DeltaV服务器支持这个特性，然后基本的WebDAV客户端（例如，那些不知道版本化的客户端）仍然可以对服务器写操作，服务器可以悄无声息的执行版本操作。在最简单的例子里，一个从基本的WebDAV客户端发送的无知的<literal>PUT</literal>可能会被服务器转化为<literal>CHECKOUT</literal>、<literal>PUT</literal>、<literal>CHECKIN</literal>。
+ </para>
</listitem>
</varlistentry>
@@ -242,46 +133,26 @@
</sect1>
<sect1 id="svn-ap-c-sect-2">
- <title>Subversion and DeltaV</title>
+ <title>Subversion和DeltaV</title>
- <para>So how <quote>compatible</quote> is Subversion with other
- DeltaV software? In two words: not very. At least not yet, not
- in Subversion 1.0.</para>
+ <para>所以Subversion与其他DeltaV的兼容性如何？两个字：不好，至少在Subversion 1.0还不好。
+ </para>
- <para>While libsvn_ra_dav sends DeltaV requests to the server, the
- Subversion client is <emphasis>not</emphasis> a general-purpose
- DeltaV client. In fact, it expects some custom features from
- the server (especially through custom <literal>REPORT</literal>
- requests). Further, mod_dav_svn is <emphasis>not</emphasis> a
- general-purpose DeltaV server. It only implements a strict
- subset of the DeltaV specification. A more general WebDAV or
- DeltaV client may very well be able to interoperate against it,
- but only if that client operates within the narrow confines of
- those features that the server has implemented. The Subversion
- development team plans to address general WebDAV
- interoperability in a future release of Subversion.</para>
+ <para>当libsvn_ra_dav发送DeltaV到服务器，Subversion客户端<emphasis>不是</emphasis>一个普通目的的DeltaV客户端。实际上，它希望服务器一些自定义的特性（特别是通过自定义的<literal>REPORT</literal>请求）。更进一步，mod_dav_svn<emphasis>不是</emphasis>一个普通目的的DeltaV服务器，它只实现了DeltaV的一个严格子集，一个更加普通的WebDAV或DeltaV客户端可能与之很好的交互工作，但是只有在服务器非常窄的已经实现的特性范围之内。Subversion开发团队计划会设法在以后的版本中完成普通的WebDAV交互性。
+ </para>
<sect2 id="svn-ap-c-sect-2.1">
- <title>Mapping Subversion to DeltaV</title>
+ <title>影射Subversion到DeltaV</title>
- <para>Here is a very <quote>high-level</quote> description of
- how various Subversion client operations use DeltaV. In many
- cases, these explanations are gross oversimplifications. They
- should <emphasis>not</emphasis> be taken as a substitute for
- reading Subversion's source code or talking with its
- developers.</para>
+ <para>这里是多种Subversion客户端如何使用DeltaV操作的一个非常<quote>高级别</quote>描述。在很多种情况下，这些解释过于粗略，这<emphasis>不</emphasis>能作为阅读Subversion源代码和与开发者交谈的替代。
+ </para>
<variablelist>
<varlistentry>
<term>svn checkout/list</term>
<listitem>
- <para>
- Perform a <literal>PROPFIND</literal> of depth 1 on the
- collection to get a list of immediate children. Perform
- a <literal>GET</literal> (and possibly a
- <literal>PROPFIND</literal>) on each child. Recurse
- into collections and repeat.
+ <para>对集合执行一个深度为1的<literal>PROPFIND</literal>来得到直接孩子的列表，对每个孩子执行一个<literal>GET</literal>（也可能是一个<literal>PROPFIND</literal>），递轨道集合并且重复。
</para>
</listitem>
</varlistentry>
@@ -290,12 +161,7 @@
<term>svn commit</term>
<listitem>
<para>
- Create an activity with <literal>MKACTIVITY</literal>,
- and do a <literal>CHECKOUT</literal> of each changed
- item, followed by a <literal>PUT</literal> of new data.
- Finally, a <literal>MERGE</literal> request causes an
- implicit <literal>CHECKIN</literal> of all working
- resources.
+ 使用<literal>MKACTIVITY</literal>创建一个活动，然后对每个修改项目执行一个<literal>CHECKOUT</literal>，紧跟一个对新数据的<literal>PUT</literal>。最终，一个<literal>MERGE</literal>请求导致一个隐含的对所有工作资源的<literal>CHECKIN</literal>。
</para>
</listitem>
</varlistentry>
@@ -304,15 +170,7 @@
<term>svn update/switch/status/merge/diff</term>
<listitem>
<para>
- Send a custom <literal>REPORT</literal> request that
- describes the mixed-revision (and mixed-URL) state of
- the working copy. The server sends a custom response
- that describes which items need updating and includes
- binary deltas of file contents. Parses the response.
- For updates and switches, install the new data in the
- working copy. For diff and merge commands, compare the
- data to the working copy, possibly applying changes as
- local modifications.
+ 发送一个自定义的描述工作拷贝混合修订版本（和混合URL）状态的<literal>REPORT</literal>请求，服务器发送一个描述需要更新的项目和文件内容增量数据的响应。解析响应，对于update和switche，在工作拷贝安装新数据，对于diff和merge，与工作拷贝的数据比较，应用修改作为本地修改。
</para>
</listitem>
</varlistentry>
@@ -322,22 +180,13 @@
</sect2>
<sect2 id="svn-ap-c-sect-2.2">
- <title>Autoversioning Support</title>
+ <title>自动版本化支持</title>
- <para>At the time of writing, the truth is that there are very
- few DeltaV clients in the world; RFC 3253 is still relatively
- new. However users do have access to <quote>generic</quote>
- clients, because almost every modern operating system now has
- an integrated basic WebDAV client. With this in mind,
- Subversion developers realized that if Subversion 1.0 was to
- have <emphasis>any</emphasis> interoperability features,
- support for DeltaV autoversioning would be the best
- approach.</para>
+ <para>在写作的时候，有一个事实就是这个世界只有很少的DeltaV客户端；RFC 3253一直是相对比较新。然而用户有一些<quote>普通的</quote>客户端，因为几乎所有的现代操作系统现在拥有集成的基本WebDAV客户端，因为这一点，Subversion开发者认识到如果Subversion 1.0可以支持DeltaV自动版本化这一交互特性会是最好的方法。
+ </para>
- <para>To activate autoversioning in mod_dav_svn, use the
- <literal>SVNAutoversioning</literal> directive within the
- <filename>httpd.conf</filename> <literal>Location</literal>
- block, like so:</para>
+ <para>为了激活mod_dav_svn的自动版本化，使用<filename>httpd.conf</filename> <literal>Location</literal>区块的<literal>SVNAutoversioning</literal>指示，例如：
+ </para>
<screen>
<Location /repos>
@@ -347,87 +196,37 @@
</Location>
</screen>
- <para>Normally, if a generic WebDAV client attempted a
- <literal>PUT</literal> to a path within your repository
- location, mod_dav_svn would outright reject the request. (It
- normally only allows such operations on <quote>working
- resources</quote> within DeltaV <quote>activities</quote>.)
- With <literal>SVNAutoversioning</literal> turned on, however,
- the server interprets the <literal>PUT</literal> request as an
- internal <literal>MKACTIVITY</literal>,
- <literal>CHECKOUT</literal>, <literal>PUT</literal>, and
- <literal>CHECKIN</literal>. A generic log message is
- auto-generated, and a new filesystem revision is
- created.</para>
-
- <para>Because so many operating systems already have integrated
- WebDAV abilities, the use case for this feature borders on
- fantastical: imagine an office of ordinary users running
- Microsoft Windows or Mac OS. Each computer
- <quote>mounts</quote> the Subversion repository, which appears
- to be an ordinary network share. They use the server as they
- always do: open files from the server, edit them, and
- save them back to the server. But in this fantasy, the server
- is automatically versioning everything. Later on, a sysadmin
- can use a Subversion client to search and retrieve all older
- versions.</para>
-
- <para>Is this fantasy real? Not quite. The main snag is that
- Subversion 1.0 has no support whatsoever for the WebDAV
- <literal>LOCK</literal> or <literal>UNLOCK</literal> methods.
- Most operating system DAV clients attempt to
- <literal>LOCK</literal> a resource opened directly from a
- DAV-mounted network share. For now, users may have to copy a
- file from the DAV share to local disk, edit the file, then
- copy it back again. Not ideal autoversioning, but still
- doable.</para>
+ <para>通常情况下，如果一个原始的WebDAV客户端尝试<literal>PUT</literal>到你的版本库位置的一个路径，mod_dav_svn会直接拒绝这个请求。（通常只允许对于DeltaV<quote>活动</quote>里面的对于<quote>工作资源</quote>的操作。）通过打开<literal>SVNAutoversioning</literal>，无论何时，服务器会把<literal>PUT</literal>请求转化为内部的<literal>MKACTIVITY</literal>、<literal>CHECKOUT</literal>、<literal>PUT</literal>和<literal>CHECKIN</literal>。一个普通的日志信息是自动生成的，并且创建一个新的文件系统修订版本。
+ </para>
+
+ <para>因为有这样多的操作系统已经集成了WebDAV能力，这个特性的用例近似于空想：想象一个普通用户运行Microsoft Windows或Mac OS的办公室，每个电脑<quote>装配</quote>了一个Subversion版本库，作为一个普通的网络共享。他们向普通目录一样操作服务器：从服务器打开文件，修改并且保存回服务器。但在这个幻想中，服务器自动版本化所有的事情，之后，一个系统管理员可以使用Subversion客户端来查找和检索所有旧的版本。
+ </para>
+
+ <para>这个幻想是现实吗？完全不是，主要的障碍是Subversion 1.0不支持WebDAV的<literal>LOCK</literal>方法<literal>UNLOCK</literal>，大多数操作系统的DAV客户端尝试<literal>LOCK</literal>一个直接从DAV装配的网络共享的资源，到目前为止，用户必须要把文件从DAV共享拷贝到本地磁盘，编辑文件，然后再拷贝回去。没有理想的自动版本化，但还是可行的。
+ </para>
</sect2>
<sect2 id="svn-ap-c-sect-2.3">
- <title>The mod_dav_lock Alternative</title>
+ <title>选择mod_dav_lock</title>
- <para>The mod_dav Apache module is a complex beast: it
- understands and parses all of the WebDAV and DeltaV methods,
- yet it depends on a back-end <quote>provider</quote> to
- access the resources themselves.</para>
-
- <para>In its simplest incarnation, a user can use mod_dav_fs as
- a provider for mod_dav. mod_dav_fs uses the ordinary
- filesystem to store files and directories, and only
- understands vanilla WebDAV methods, not DeltaV.</para>
-
- <para>Subversion, on the other hand, uses mod_dav_svn as a
- provider for mod_dav. mod_dav_svn understands all WebDAV
- methods except <literal>LOCK</literal>, and understands a
- sizable subset of DeltaV methods. It accesses data in the
- Subversion repository, rather than in the real filesystem.
- Subversion 1.0 doesn't support locking, because it would
- actually be quite difficult to implement, since Subversion uses
- the copy-modify-merge model.<footnote><para>Subversion may
- someday develop a reserved-checkout locking model that can
- live peaceably with copy-modify-merge, but it probably won't
- happen soon.</para></footnote></para>
-
- <para>In Apache httpd-2.0, mod_dav supports the
- <literal>LOCK</literal> method by tracking locks in a private
- database, assuming that the provider is willing to accept
- them. In Apache httpd-2.1 or later, however, this locking
- support has been broken into an independent module,
- mod_dav_lock. It allows any mod_dav provider to take
- advantage of the lock database, including mod_dav_svn, even
- though mod_dav_svn doesn't actually understand locking.</para>
-
- <para>Confused yet?</para>
-
- <para>In a nutshell, you can use mod_dav_lock in Apache
- httpd-2.1 (or later) to create the
- <emphasis>illusion</emphasis> that mod_dav_svn is honoring
- <literal>LOCK</literal> requests. Make sure mod_dav_lock is
- either compiled into httpd, or being loaded in your
- <filename>httpd.conf</filename>. Then simply add the
- <literal>DAVGenericLockDB</literal> directive to your
- <literal>Location</literal> like so:</para>
+ <para>Apache模块mod_dav是一个复杂的野兽：它理解和解析所有的WebDAV和DeltaV方法，然而它依赖于后端<quote>提供者</quote>来访问资源本身。
+ </para>
+
+ <para>在最简单的化身里，一个用户可以使用mod_dav_fs可以作为mod_dav的提供者，mod_dav_fs使用普通的文件系统来存放文件和目录，只理解平凡的WebDAV方法，不是DeltaV。
+ </para>
+
+ <para>在另一方面，Subversion使用mod_dav_svn作为mod_dav的提供者，mod_dav_svn理解除了<literal>LOCK</literal>以外的所有WebDAV方法，并且理解相当大的DeltaV方法子集，它访问Subversion版本库的数据，而不是真实的文件系统。Subversion 1.0不支持锁定，因为这会非常难于实现，因为Subversion使用拷贝-修改-合并模型。<footnote><para>Subversion可能有一天会开发一个保留检出的锁定模型，可以与拷贝-修改-合并和平相处，但是可能不会立刻发生。
+ </para></footnote></para>
+
+ <para>在Apache httpd-2.0里，mod_dav可以通过追踪私有数据库的锁来支持<literal>LOCK</literal>方法，假定提供者会乐于接受这一点。在Apache httpd-2.1或以后的版本，这个锁定支持会拆到一个独立的模块，mod_dav_lock。它允许任何mod_dav提供者利用锁数据库的好处，包括mod_dav_svn，即使mod_dav_svn实际上不理解锁定。
+ </para>
+
+ <para>感到困惑？</para>
+
+ <para>简言之，你可以使用Apache
+ httpd-2.1（或更晚的）的mod_dav_lock来创建一个错觉，也就是mod_dav_svn负责了<literal>LOCK</literal>操作。确定mod_dav_lock已经编译到httpd或已经在<filename>httpd.conf</filename>中加载，然后只需要在<literal>Location</literal>简单的添加如下的<literal>DAVGenericLockDB</literal>指示：
+ </para>
<screen>
<Location /repos>
@@ -438,92 +237,49 @@
</Location>
</screen>
- <para>This technique is a risky business; in some sense, the
- mod_dav_svn is now lying to the WebDAV client. It claims to
- accept the <literal>LOCK</literal> request, but in reality the
- lock isn't being enforced at all levels. If a second WebDAV
- client attempts to <literal>LOCK</literal> the same resource,
- then mod_dav_lock will notice and correctly deny the request.
- But there's absolutely nothing preventing an ordinary
- Subversion client from changing the file via a normal
- <command>svn commit</command>! If you use this technique,
- you're giving users the opportunity to stomp on each others'
- changes. In particular, a WebDAV client might accidentally
- overwrite a change committed by a regular Subversion client.</para>
-
- <para>On the other hand, if you set up your environment very
- carefully, you may mitigate the risk. For example, if
- <emphasis>all</emphasis> of your users are working though
- basic WebDAV clients (rather than Subversion clients), then
- things should be fine.</para>
+ <para>这个技术是一个有危险的业务；在一些情况，mod_dav_svn现在已经接近WebDAV客户端，它宣称接受<literal>LOCK</literal>请求，但是实际上锁并不是在所有的级别上强制执行。如果第二个WebDAV客户端尝试<literal>LOCK</literal>锁住同样的资源，然后mod_dav_lock会注意到并且正确的拒绝这个请求，但是完全没有办法来防止一个普通的Subversion客户端使用<command>svn commit</command>来修改文件！如果你使用这个技术，你给用户权利来践踏其他人的修改，更具体一点，一个WebDAV客户端会不小心覆盖普通Subversion客户端提交的修改。
+ </para>
+
+ <para>在另一方面，如果你小心设置你的环境变量，你会减轻这个风险，例如，如果<emphasis>所有</emphasis>用户使用WebDAV客户端（而不是Subversion客户端），然后事情变得美好了。
+ </para>
</sect2>
</sect1>
<sect1 id="svn-ap-c-sect-3">
- <title>Autoversioning Interoperability</title>
+ <title>自动版本化交互性</title>
- <para>In this section, we'll describe the most common generic
- WebDAV clients (at the time of writing), and how well they
- operate against a mod_dav_svn server using the
- <literal>SVNAutoversioning</literal> directive. RFC 2518 is a
- bit large, and perhaps a bit too flexible. Every WebDAV
- client behaves slightly differently, and creates slightly
- different problems.</para>
+ <para>在这个小节，我们会描述最普通的原始WebDAV客户端（写作的时刻），和它们是如何与使用<literal>SVNAutoversioning</literal>指示的mod_dav_svn服务器的运作。RFC 2518是一个有点大，并且有一点太灵活。每个WebDAV客户端的行为都有些许区别，并且产生许多不同的小问题。
+ </para>
<!-- list of subsections goes here. -->
<sect2 id="svn-ap-c-sect-3.1">
- <title>Win32 WebFolders</title>
+ <title>Win32网络文件夹</title>
- <para>Windows 98, 2000, and XP have an integrated WebDAV client
- known as <quote>WebFolders</quote>. On Windows 98, the
- feature might need to be explicitly installed; if present, a
- <quote>WebFolders</quote> directory appears directly within My
- Computer. On Windows 2000 and XP, simply open My Network
- Places, and run the Add Network Place icon. When prompted,
- enter the WebDAV URL. The shared folder will appear within My
- Network Places.</para>
+ <para>Windows 98、2000和XP有一个集成的WebDAV客户端叫做<quote>网络文件夹</quote>，在Windows 98，这个特性需要明确安装；如果提供，一个<quote>网络文件夹</quote>就会出现在我的电脑，在Windows 2000和XP，只需要简单得打开我的网络位置，运行添加网络位置图标。当出现提示，输入一个WebDAV的URL，我的网络位置中就会出现一个共享文件夹。
+ </para>
- <para>Most write operations work fine against an autoversioning
- mod_dav_svn server, but there are a few problems:</para>
+ <para>大多数写操作对于自动版本化的mod_dav_svn服务器工作正常，但是有一些问题：
+ </para>
<itemizedlist>
<listitem>
- <para>If a Windows XP computer is a member of an NT Domain,
- then it seems to be unable to connect to the WebDAV share.
- It repeatedly asks for a name and password, even when the
- Apache server isn't issuing an authentication challenge!
- If the machine isn't part of an NT Domain, then the share
- is mounted without a problem.</para>
+ <para>如果一个Windows XP电脑是一个NT域的成员，它看起来不能连接到WebDAV共享，重复提示要输入用户名和密码，即使Apache服务器没有要求进行认证！如果这个机器不是NT域的一部分，这个共享可以成功装载。
+ </para>
- <para>This problem seems to stem from changes in the way
- Windows XP creates WebFolder shortcuts (
- <filename>.lnk</filename> files). It sometimes replaces
- the URL of the WebDAV share with a Windows
- <quote>UNC</quote> (Universal Naming Convention) path
- instead. This causes Explorer to attempt a connection
- using SMB instead of HTTP.</para>
+ <para>这个问题源于Windows XP创建网络文件夹快捷方式（<filename>.lnk</filename>文件）的方法的白边。它有时候会使用<quote>UNC</quote> （Universal Naming Convention） 路径来代替WebDAV共享URL，这导致资源管理器尝试使用SMB而不是HTTP来进行连接。
+ </para>
- <para>A workaround for this problem is to create the
- <filename>.lnk</filename> shortcut on a Windows 2000
- computer and then copy this shortcut to the Windows XP
- computer. It would probably also be possible to
- <quote>fix</quote> the shortcut using a HEX editor, if
- one were to reverse-engineer the <filename>.lnk</filename>
- file format.</para>
+ <para>这个问题的解决方法是在Windows 2000创建<filename>.lnk</filename>快捷方式，然后拷贝到Windows XP电脑，如果有人可以逆转<filename>.lnk</filename>文件的格式，也可以使用十六进制编辑器来<quote>修正</quote>快捷方式。
+ </para>
</listitem>
<listitem>
- <para>A file can't be opened for direct editing from the
- share; it always comes up read-only. The mod_dav_lock
- technique doesn't help, because WebFolders doesn't use the
- <literal>LOCK</literal> method at all. The previously
- mentioned <quote>copy, edit, re-copy</quote> method does
- work, however. The file on the share can be successfully
- overwritten by a locally edited copy.</para>
+ <para>一个文件不可以直接在共享中打开编辑；它可能一直是只读的。mod_dav_lock技术也无能为力，因为网络文件夹根本不使用<literal>LOCK</literal>方法，前面提到的<quote>拷贝、编辑和再拷贝</quote>根本不工作。在共享中的文件可以成功的被本地修改的拷贝覆盖。
+ </para>
</listitem>
</itemizedlist>
@@ -533,36 +289,16 @@
<sect2 id="svn-ap-c-sect-3.2">
<title>Mac OS X</title>
- <para>Apple's OS X operating system has an integrated WebDAV
- client. From the Finder, select the <quote>Connect to
- Server</quote> item from the Go menu. Enter a WebDAV URL,
- and it appears as a disk on the desktop, just like any file
- server.<footnote><para>Unix users can also run <command>mount
- -t webdav URL /mountpoint</command>.</para></footnote></para>
+ <para>Apple的OS X操作系统也集成了WebDAV客户端，从Finder选择Go菜单的<quote>Connect to
+ Server</quote>，输入一个WebDAV的URL，它会作为一个磁盘在桌面出现，就像任何文件服务器。<footnote><para>Unix用户也可以运行<command>mount
+ -t webdav URL /mountpoint</command>。
+ </para></footnote></para>
- <para>Unfortunately, this client refuses to work against an
- autoversioning mod_dav_svn because of its lack of
- <literal>LOCK</literal> support. Mac OS X discovers the
- missing <literal>LOCK</literal> ability during the initial
- HTTP <literal>OPTIONS</literal> feature exchange, and thus
- decides to mount the Subversion repository as a read-only
- share. After that, no write operations are possible at all.
- In order to mount the repository as a read-write share, you
- <emphasis>must</emphasis> use the mod_dav_lock trick discussed
- previously. Once locking seems to work, the share behaves
- very nicely: files can be opened directly in read/write mode,
- although each save operation will cause the client to do a
- <literal>PUT</literal> to a temporary location, a
- <literal>DELETE</literal> of original file, and a
- <literal>MOVE</literal> of the temporary resource to the
- original filename. That's three new Subversion revisions per
- save!</para>
-
- <para>One more word of warning: OS X's WebDAV client can be
- overly sensitive to HTTP redirects. If you're unable to mount
- the repository at all, you may need to enable the
- <literal>BrowserMatch</literal> directive in your
- <filename>httpd.conf</filename>:</para>
+ <para>很不幸，客户端拒绝与一个自动版本化的mod_dav_svn工作，因为它缺乏<literal>LOCK</literal>支持，Mac OS X在初始化HTTP的<literal>OPTIONS</literal>特性交换时会发现缺失了<literal>LOCK</literal>能力，因而决定以只读方式装配Subversion版本库，之后，不可以进行写操作。为了将版本库按照读写方式装配，你<emphasis>必须</emphasis>使用前面讨论的mod_dav_lock技巧。一旦锁定看起来工作了，共享会运作良好：文件可以直接以读/写模式打开，尽管每次存储操作会导致客户端对临时位置执行一个<literal>PUT</literal>，对原文件的<literal>DELETE</literal>操作和把临时资源<literal>MOVE</literal>到原文件。每次存盘会产生三个新的Subversion修订版本！
+ </para>
+
+ <para>还要警告一点：OS X的WebDAV客户端可以对HTTP重定向完全敏感，如果你不能装配版本库，你可以在<filename>httpd.conf</filename>开启<literal>BrowserMatch</literal>指示：
+ </para>
<screen>
BrowserMatch "^WebDAVFS/1.[012]" redirect-carefully
@@ -573,41 +309,28 @@
<sect2 id="svn-ap-c-sect-3.3">
<title>Unix: Nautilus 2</title>
- <para>Nautilus is the official file manager/browser for the
- GNOME desktop. Its main home page is at <systemitem
- class="url">http://www.gnome.org/projects/nautilus/</systemitem>.
- By simply typing a WebDAV URL into the Nautilus window,
- the DAV share appears like a local filesystem.</para>
+ <para>Nautilus是GNOME桌面的官方文件管理器/浏览器，它的主页在<systemitem
+ class="url">http://www.gnome.org/projects/nautilus/</systemitem>，只需要在Nautilus窗口中输入一个WebDAV的URL，DAV共享就会像本地磁盘一样出现。
+ </para>
- <para>In general, Nautilus 2 works reasonably well against an
- autoversioning mod_dav_svn, with the following caveats:</para>
+ <para>通常情况下，Nautilus 2与自动版本化的mod_dav_svn一起工作相当的好，只是有下面一些警告：
+ </para>
<itemizedlist>
<listitem>
- <para>Any files opened directly from the share are treated
- as read-only. Even the mod_dav_lock trick seems to have
- no effect. It seems that Nautilus never issues the
- <literal>LOCK</literal> method at all. The <quote>copy
- locally, edit, copy back</quote> trick does work, however.
- Unfortunately, Nautilus overwrites the old file by issuing
- a <literal>DELETE</literal> first, which creates an extra
- revision.</para>
+ <para>任何在共享里直接打开的文件是只读的，即使mod_dav_lock的技巧也看起来无效。Nautilus看起来从没有关注过<literal>LOCK</literal>方法，<quote>本地拷贝、编辑和拷贝回去</quote>的技巧还可以工作，但是很不幸，Nautilus的覆盖旧文件是通过首先<literal>DELETE</literal>进行的，这创建了一个额外的修订版本。
+ </para>
</listitem>
<listitem>
- <para>When overwriting or creating a file , Nautilus first
- does a <literal>PUT</literal> of an empty file, then
- overwrites it with a second <literal>PUT</literal>. This
- creates two Subversion filesystem revisions, rather than
- one.</para>
+ <para>当覆盖或创建一个文件，Nautilus首先<literal>PUT</literal>一个空文件，然后使用第二个<literal>PUT</literal>覆盖它，这创建了两个Subversion文件系统修订版本，而不是一个。
+ </para>
</listitem>
<listitem>
- <para>When deleting a collection, it issues an HTTP
- <literal>DELETE</literal> on each individual child instead
- of on the collection itself. This creates a whole bunch of
- new revisions.</para>
+ <para>当删除了一个集合，它对每个独立的孩子而不是集合本身发出HTTP的<literal>DELETE</literal>操作，这会创建一系列新的修订版本。
+ </para>
</listitem>
</itemizedlist>
@@ -617,18 +340,12 @@
<sect2 id="svn-ap-c-sect-3.4">
<title>Linux davfs2</title>
- <para>Linux davfs2 is a filesystem module for the Linux kernel,
- whose development is located at <systemitem
- class="url">http://dav.sourceforge.net/</systemitem>. Once
- installed, a WebDAV network share can be mounted with the
- usual Linux <command>mount</command> command.</para>
-
- <para>The word on the street is that this DAV client doesn't
- work at all with mod_dav_svn's autoversioning. Every single
- attempt to write to the server is preceded by a
- <literal>LOCK</literal> request, which mod_dav_svn doesn't
- support. At this time, there is no data indicating whether
- the use of mod_dav_lock resolves this problem.</para>
+ <para>Linux davfs2是一个Linux内核的文件系统模块，它的开发位于<systemitem
+ class="url">http://dav.sourceforge.net/</systemitem>。一旦安装，一个WebDAV网络共享可以使用普通的Linux的<command>mount</command>命令装配。
+ </para>
+
+ <para>一个公开的秘密就是DAV客户端不会与mod_dav_svn的自动版本化完全工作正常，即使一个单独对服务器的写尝试需要<literal>LOCK</literal>请求作为前提，而这是mod_dav_svn不支持的。此时，还没有数据表明是否可以使用mod_dav_lock解决这个问题。
+ </para>
</sect2>
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