docs/versions/7.1.0/reference/be/protocol-buffer.mdx - bazel - Git at Google

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 <h1 class="page-title">Protocol Buffer Rules</h1>

 {% dynamic setvar source_file "src/main/java/com/google/devtools/build/docgen/templates/be/rules.vm" %}
 {% dynamic setvar version "7.1.0" %}
 {% dynamic setvar original_path "/reference/be/protocol-buffer" %}
 {% include "_buttons.html" %}


 <h2>Rules</h2>
 <ul>
   <li>
     <a href="#proto_lang_toolchain">
       proto_lang_toolchain    </a>
   </li>
   <li>
     <a href="#proto_library">
       proto_library    </a>
   </li>
 </ul>

   <h2 id="proto_lang_toolchain">
     proto_lang_toolchain
   </h2>

   <a class="button button-with-icon" href="https://github.com/bazelbuild/bazel/blob/master/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoLangToolchainRule.java" target="_blank">
   View rule source<span class="material-icons icon-after" aria-hidden="true">open_in_new</span>
   </a>

   <pre class="rule-signature">proto_lang_toolchain(<a href="#proto_lang_toolchain.name">name</a>, <a href="#proto_lang_toolchain.blacklisted_protos">blacklisted_protos</a>, <a href="#proto_lang_toolchain.command_line">command_line</a>, <a href="common-definitions.html#common.compatible_with">compatible_with</a>, <a href="common-definitions.html#common.deprecation">deprecation</a>, <a href="common-definitions.html#common.distribs">distribs</a>, <a href="common-definitions.html#common.exec_compatible_with">exec_compatible_with</a>, <a href="common-definitions.html#common.exec_properties">exec_properties</a>, <a href="common-definitions.html#common.features">features</a>, <a href="common-definitions.html#typical.licenses">licenses</a>, <a href="#proto_lang_toolchain.mnemonic">mnemonic</a>, <a href="#proto_lang_toolchain.output_files">output_files</a>, <a href="#proto_lang_toolchain.plugin">plugin</a>, <a href="#proto_lang_toolchain.plugin_format_flag">plugin_format_flag</a>, <a href="#proto_lang_toolchain.progress_message">progress_message</a>, <a href="#proto_lang_toolchain.proto_compiler">proto_compiler</a>, <a href="common-definitions.html#common.restricted_to">restricted_to</a>, <a href="#proto_lang_toolchain.runtime">runtime</a>, <a href="common-definitions.html#common.tags">tags</a>, <a href="common-definitions.html#common.target_compatible_with">target_compatible_with</a>, <a href="common-definitions.html#common.testonly">testonly</a>, <a href="common-definitions.html#common.visibility">visibility</a>)</pre>


 <p>If using Bazel, please load the rule from <a href="https://github.com/bazelbuild/rules_proto">
    https://github.com/bazelbuild/rules_proto</a>.
 </p>

 <p>
 Specifies how a LANG_proto_library rule (e.g., <code>java_proto_library</code>) should invoke the
 proto-compiler.
 Some LANG_proto_library rules allow specifying which toolchain to use using command-line flags;
 consult their documentation.
 </p>

 <p>Normally you should not write those kind of rules unless you want to
 tune your Java compiler.</p>

 <p>
 There's no compiler. The proto-compiler is taken from the proto_library rule we attach to. It is
 passed as a command-line flag to Blaze.
 Several features require a proto-compiler to be invoked on the proto_library rule itself.
 It's beneficial to enforce the compiler that LANG_proto_library uses is the same as the one
 <code>proto_library</code> does.
 </p>

 <h4>Examples</h4>

 <p>A simple example would be:
 </p>

 <pre class="code">
 proto_lang_toolchain(
     name = "javalite_toolchain",
     command_line = "--javalite_out=shared,immutable:$(OUT)",
     plugin = ":javalite_plugin",
     runtime = ":protobuf_lite",
 )
 </pre>


   <h3 id="proto_lang_toolchain_args">Arguments</h3>
   <table class="table table-condensed table-bordered table-params">
     <colgroup>
       <col class="col-param" />
       <col class="param-description" />
     </colgroup>
     <thead>
       <tr>
         <th colspan="2">Attributes</th>
       </tr>
     </thead>
     <tbody>
       <tr>
         <td id="proto_lang_toolchain.name"><code>name</code></td>
         <td>
           <p><a href="/versions/7.1.0/concepts/labels#target-names">Name</a>; required</p>
           <p>A unique name for this target.</p>

         </td>
       </tr>
                 <tr>
         <td id="proto_lang_toolchain.blacklisted_protos">
           <code>blacklisted_protos</code>
         </td>
         <td>
                     <p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
                             No code will be generated for files in the <code>srcs</code> attribute of
         <code>blacklisted_protos</code>.
         This is used for .proto files that are already linked into proto runtimes, such as
         <code>any.proto</code>.

         </td>
       </tr>
                       <tr>
         <td id="proto_lang_toolchain.command_line">
           <code>command_line</code>
         </td>
         <td>
                     <p>String; required</p>
                             This value will be passed to proto-compiler to generate the code. Only include the parts
         specific to this code-generator/plugin (e.g., do not include -I parameters)
         <ul>
           <li><code>$(OUT)</code> is LANG_proto_library-specific. The rules are expected to define
               how they interpret this variable. For Java, for example, $(OUT) will be replaced with
               the src-jar filename to create.</li>
         </ul>

         </td>
       </tr>
                                                                                             <tr>
         <td id="proto_lang_toolchain.mnemonic">
           <code>mnemonic</code>
         </td>
         <td>
                     <p>String; default is <code>"GenProto"</code></p>
                             This value will be set as the mnemonic on protoc action.

         </td>
       </tr>
                       <tr>
         <td id="proto_lang_toolchain.output_files">
           <code>output_files</code>
         </td>
         <td>
                     <p>String; default is <code>"legacy"</code></p>
                             Controls how <code>$(OUT)</code> in <code>command_line</code> is formatted, either by
         a path to a single file or output directory in case of multiple files.
         Possible values are: "single", "multiple".

         </td>
       </tr>
                       <tr>
         <td id="proto_lang_toolchain.plugin">
           <code>plugin</code>
         </td>
         <td>
                     <p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
                             If provided, will be made available to the action that calls the proto-compiler, and will be
         passed to the proto-compiler:
         <code>--plugin=protoc-gen-PLUGIN=&lt;executable&gt;.</code>

         </td>
       </tr>
                       <tr>
         <td id="proto_lang_toolchain.plugin_format_flag">
           <code>plugin_format_flag</code>
         </td>
         <td>
                     <p>String; default is <code>""</code></p>
                             If provided, this value will be passed to proto-compiler to use the plugin. The value must
         contain a single %s which is replaced with plugin executable.
         <code>--plugin=protoc-gen-PLUGIN=&lt;executable&gt;.</code>

         </td>
       </tr>
                       <tr>
         <td id="proto_lang_toolchain.progress_message">
           <code>progress_message</code>
         </td>
         <td>
                     <p>String; default is <code>"Generating proto_library %{label}"</code></p>
                             This value will be set as the progress message on protoc action.

         </td>
       </tr>
                       <tr>
         <td id="proto_lang_toolchain.proto_compiler">
           <code>proto_compiler</code>
         </td>
         <td>
                     <p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
                             The proto compiler executable.
         If provided, this target will be used as a proto-compiler to generate the code.

         </td>
       </tr>
                                 <tr>
         <td id="proto_lang_toolchain.runtime">
           <code>runtime</code>
         </td>
         <td>
                     <p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
                             A language-specific library that the generated code is compiled against.
         The exact behavior is LANG_proto_library-specific.
         Java, for example, should compile against the runtime.

         </td>
       </tr>
                                                       </tbody>
   </table>
   <h2 id="proto_library">
     proto_library
   </h2>

   <a class="button button-with-icon" href="https://github.com/bazelbuild/bazel/blob/master/src/main/java/com/google/devtools/build/lib/rules/proto/BazelProtoLibraryRule.java" target="_blank">
   View rule source<span class="material-icons icon-after" aria-hidden="true">open_in_new</span>
   </a>

   <pre class="rule-signature">proto_library(<a href="#proto_library.name">name</a>, <a href="#proto_library.deps">deps</a>, <a href="#proto_library.srcs">srcs</a>, <a href="common-definitions.html#typical.data">data</a>, <a href="#proto_library.allow_exports">allow_exports</a>, <a href="common-definitions.html#common.compatible_with">compatible_with</a>, <a href="common-definitions.html#common.deprecation">deprecation</a>, <a href="common-definitions.html#common.distribs">distribs</a>, <a href="common-definitions.html#common.exec_compatible_with">exec_compatible_with</a>, <a href="common-definitions.html#common.exec_properties">exec_properties</a>, <a href="#proto_library.exports">exports</a>, <a href="common-definitions.html#common.features">features</a>, <a href="#proto_library.import_prefix">import_prefix</a>, <a href="common-definitions.html#typical.licenses">licenses</a>, <a href="common-definitions.html#common.restricted_to">restricted_to</a>, <a href="#proto_library.strip_import_prefix">strip_import_prefix</a>, <a href="common-definitions.html#common.tags">tags</a>, <a href="common-definitions.html#common.target_compatible_with">target_compatible_with</a>, <a href="common-definitions.html#common.testonly">testonly</a>, <a href="common-definitions.html#common.visibility">visibility</a>)</pre>


 <p>Deprecated. Please use <a href="https://github.com/bazelbuild/rules_proto">
    https://github.com/bazelbuild/rules_proto</a> instead.
 </p>

 <p>Use <code>proto_library</code> to define libraries of protocol buffers
    which may be used from multiple languages. A <code>proto_library</code> may be listed
    in the <code>deps</code> clause of supported rules, such as <code>java_proto_library</code>.
 </p>

 <p>When compiled on the command-line, a <code>proto_library</code> creates a file named
    <code>foo-descriptor-set.proto.bin</code>, which is the descriptor set for the
    messages the rule srcs. The file is a serialized <code>FileDescriptorSet</code>, which is
    described in
    <a href="https://developers.google.com/protocol-buffers/docs/techniques#self-description">
    https://developers.google.com/protocol-buffers/docs/techniques#self-description</a>.
 </p>

 <p>It only contains information about the <code>.proto</code> files directly mentioned by a
 <code>proto_library</code> rule; the collection of transitive descriptor sets is available through
 the <code>[ProtoInfo].transitive_descriptor_sets</code> Starlark provider.
 See documentation in <code>ProtoInfo.java</code>.</p>

 <p>Recommended code organization:</p>

 <ul>
 <li> One <code>proto_library</code> rule per <code>.proto</code> file.
 <li> A file named <code>foo.proto</code> will be in a rule named <code>foo_proto</code>, which
    is located in the same package.
 <li> A <code>[language]_proto_library</code> that wraps a <code>proto_library</code> named
   <code>foo_proto</code> should be called
    <code>foo_[language]_proto</code>, and be located in the same package.
 </ul>


   <h3 id="proto_library_args">Arguments</h3>
   <table class="table table-condensed table-bordered table-params">
     <colgroup>
       <col class="col-param" />
       <col class="param-description" />
     </colgroup>
     <thead>
       <tr>
         <th colspan="2">Attributes</th>
       </tr>
     </thead>
     <tbody>
       <tr>
         <td id="proto_library.name"><code>name</code></td>
         <td>
           <p><a href="/versions/7.1.0/concepts/labels#target-names">Name</a>; required</p>
           <p>A unique name for this target.</p>

         </td>
       </tr>
                 <tr>
         <td id="proto_library.deps">
           <code>deps</code>
         </td>
         <td>
                     <p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
                             The list of other <code>proto_library</code> rules that the target depends upon.
         A <code>proto_library</code> may only depend on other
         <code>proto_library</code> targets.
         It may not depend on language-specific libraries.

         </td>
       </tr>
                       <tr>
         <td id="proto_library.srcs">
           <code>srcs</code>
         </td>
         <td>
                     <p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
                             The list of <code>.proto</code> and <code>.protodevel</code> files that are
         processed to create the target. This is usually a non empty list. One usecase
         where <code>srcs</code> can be empty is an <i>alias-library</i>. This is a
         proto_library rule having one or more other proto_library in <code>deps</code>.
         This pattern can be used to e.g. export a public api under a persistent name.

         </td>
       </tr>
                                 <tr>
         <td id="proto_library.allow_exports">
           <code>allow_exports</code>
         </td>
         <td>
                     <p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
                             An optional allowlist that prevents proto library to be reexported or used in
         lang_proto_library that is not in one of the listed packages.

         </td>
       </tr>
                                                                         <tr>
         <td id="proto_library.exports">
           <code>exports</code>
         </td>
         <td>
                     <p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
                             List of proto_library targets that can be referenced via "import public" in the proto
         source.

         </td>
       </tr>
                                 <tr>
         <td id="proto_library.import_prefix">
           <code>import_prefix</code>
         </td>
         <td>
                     <p>String; default is <code>""</code></p>
                             The prefix to add to the paths of the .proto files in this rule.

         <p>When set, the .proto source files in the <code>srcs</code> attribute of this rule are
         accessible at is the value of this attribute prepended to their repository-relative path.

         <p>The prefix in the <code>strip_import_prefix</code> attribute is removed before this
         prefix is added.

         </td>
       </tr>
                                           <tr>
         <td id="proto_library.strip_import_prefix">
           <code>strip_import_prefix</code>
         </td>
         <td>
                     <p>String; default is <code>""</code></p>
                             The prefix to strip from the paths of the .proto files in this rule.

         <p>When set, .proto source files in the <code>srcs</code> attribute of this rule are
         accessible at their path with this prefix cut off.

         <p>If it's a relative path (not starting with a slash), it's taken as a package-relative
         one. If it's an absolute one, it's understood as a repository-relative path.

         <p>The prefix in the <code>import_prefix</code> attribute is added after this prefix is
         stripped.

         </td>
       </tr>
                                                       </tbody>
   </table>

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	<h1 class="page-title">Protocol Buffer Rules</h1>

	{% dynamic setvar source_file "src/main/java/com/google/devtools/build/docgen/templates/be/rules.vm" %}
	{% dynamic setvar version "7.1.0" %}
	{% dynamic setvar original_path "/reference/be/protocol-buffer" %}
	{% include "_buttons.html" %}



	<h2>Rules</h2>
	<ul>
	<li>
	<a href="#proto_lang_toolchain">
	proto_lang_toolchain </a>
	</li>
	<li>
	<a href="#proto_library">
	proto_library </a>
	</li>
	</ul>

	<h2 id="proto_lang_toolchain">
	proto_lang_toolchain
	</h2>

	<a class="button button-with-icon" href="https://github.com/bazelbuild/bazel/blob/master/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoLangToolchainRule.java" target="_blank">
	View rule source<span class="material-icons icon-after" aria-hidden="true">open_in_new</span>
	</a>

	<pre class="rule-signature">proto_lang_toolchain(<a href="#proto_lang_toolchain.name">name</a>, <a href="#proto_lang_toolchain.blacklisted_protos">blacklisted_protos</a>, <a href="#proto_lang_toolchain.command_line">command_line</a>, <a href="common-definitions.html#common.compatible_with">compatible_with</a>, <a href="common-definitions.html#common.deprecation">deprecation</a>, <a href="common-definitions.html#common.distribs">distribs</a>, <a href="common-definitions.html#common.exec_compatible_with">exec_compatible_with</a>, <a href="common-definitions.html#common.exec_properties">exec_properties</a>, <a href="common-definitions.html#common.features">features</a>, <a href="common-definitions.html#typical.licenses">licenses</a>, <a href="#proto_lang_toolchain.mnemonic">mnemonic</a>, <a href="#proto_lang_toolchain.output_files">output_files</a>, <a href="#proto_lang_toolchain.plugin">plugin</a>, <a href="#proto_lang_toolchain.plugin_format_flag">plugin_format_flag</a>, <a href="#proto_lang_toolchain.progress_message">progress_message</a>, <a href="#proto_lang_toolchain.proto_compiler">proto_compiler</a>, <a href="common-definitions.html#common.restricted_to">restricted_to</a>, <a href="#proto_lang_toolchain.runtime">runtime</a>, <a href="common-definitions.html#common.tags">tags</a>, <a href="common-definitions.html#common.target_compatible_with">target_compatible_with</a>, <a href="common-definitions.html#common.testonly">testonly</a>, <a href="common-definitions.html#common.visibility">visibility</a>)</pre>


	<p>If using Bazel, please load the rule from <a href="https://github.com/bazelbuild/rules_proto">
	https://github.com/bazelbuild/rules_proto</a>.
	</p>

	<p>
	Specifies how a LANG_proto_library rule (e.g., <code>java_proto_library</code>) should invoke the
	proto-compiler.
	Some LANG_proto_library rules allow specifying which toolchain to use using command-line flags;
	consult their documentation.
	</p>

	<p>Normally you should not write those kind of rules unless you want to
	tune your Java compiler.</p>

	<p>
	There's no compiler. The proto-compiler is taken from the proto_library rule we attach to. It is
	passed as a command-line flag to Blaze.
	Several features require a proto-compiler to be invoked on the proto_library rule itself.
	It's beneficial to enforce the compiler that LANG_proto_library uses is the same as the one
	<code>proto_library</code> does.
	</p>

	<h4>Examples</h4>

	<p>A simple example would be:
	</p>

	<pre class="code">
	proto_lang_toolchain(
	name = "javalite_toolchain",
	command_line = "--javalite_out=shared,immutable:$(OUT)",
	plugin = ":javalite_plugin",
	runtime = ":protobuf_lite",
	)
	</pre>



	<h3 id="proto_lang_toolchain_args">Arguments</h3>
	<table class="table table-condensed table-bordered table-params">
	<colgroup>
	<col class="col-param" />
	<col class="param-description" />
	</colgroup>
	<thead>
	<tr>
	<th colspan="2">Attributes</th>
	</tr>
	</thead>
	<tbody>
	<tr>
	<td id="proto_lang_toolchain.name"><code>name</code></td>
	<td>
	<p><a href="/versions/7.1.0/concepts/labels#target-names">Name</a>; required</p>
	<p>A unique name for this target.</p>

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.blacklisted_protos">
	<code>blacklisted_protos</code>
	</td>
	<td>
	<p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
	No code will be generated for files in the <code>srcs</code> attribute of
	<code>blacklisted_protos</code>.
	This is used for .proto files that are already linked into proto runtimes, such as
	<code>any.proto</code>.

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.command_line">
	<code>command_line</code>
	</td>
	<td>
	<p>String; required</p>
	This value will be passed to proto-compiler to generate the code. Only include the parts
	specific to this code-generator/plugin (e.g., do not include -I parameters)
	<ul>
	<li><code>$(OUT)</code> is LANG_proto_library-specific. The rules are expected to define
	how they interpret this variable. For Java, for example, $(OUT) will be replaced with
	the src-jar filename to create.</li>
	</ul>

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.mnemonic">
	<code>mnemonic</code>
	</td>
	<td>
	<p>String; default is <code>"GenProto"</code></p>
	This value will be set as the mnemonic on protoc action.

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.output_files">
	<code>output_files</code>
	</td>
	<td>
	<p>String; default is <code>"legacy"</code></p>
	Controls how <code>$(OUT)</code> in <code>command_line</code> is formatted, either by
	a path to a single file or output directory in case of multiple files.
	Possible values are: "single", "multiple".

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.plugin">
	<code>plugin</code>
	</td>
	<td>
	<p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
	If provided, will be made available to the action that calls the proto-compiler, and will be
	passed to the proto-compiler:
	<code>--plugin=protoc-gen-PLUGIN=<executable>.</code>

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.plugin_format_flag">
	<code>plugin_format_flag</code>
	</td>
	<td>
	<p>String; default is <code>""</code></p>
	If provided, this value will be passed to proto-compiler to use the plugin. The value must
	contain a single %s which is replaced with plugin executable.
	<code>--plugin=protoc-gen-PLUGIN=<executable>.</code>

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.progress_message">
	<code>progress_message</code>
	</td>
	<td>
	<p>String; default is <code>"Generating proto_library %{label}"</code></p>
	This value will be set as the progress message on protoc action.

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.proto_compiler">
	<code>proto_compiler</code>
	</td>
	<td>
	<p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
	The proto compiler executable.
	If provided, this target will be used as a proto-compiler to generate the code.

	</td>
	</tr>
	<tr>
	<td id="proto_lang_toolchain.runtime">
	<code>runtime</code>
	</td>
	<td>
	<p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
	A language-specific library that the generated code is compiled against.
	The exact behavior is LANG_proto_library-specific.
	Java, for example, should compile against the runtime.

	</td>
	</tr>
	</tbody>
	</table>
	<h2 id="proto_library">
	proto_library
	</h2>

	<a class="button button-with-icon" href="https://github.com/bazelbuild/bazel/blob/master/src/main/java/com/google/devtools/build/lib/rules/proto/BazelProtoLibraryRule.java" target="_blank">
	View rule source<span class="material-icons icon-after" aria-hidden="true">open_in_new</span>
	</a>

	<pre class="rule-signature">proto_library(<a href="#proto_library.name">name</a>, <a href="#proto_library.deps">deps</a>, <a href="#proto_library.srcs">srcs</a>, <a href="common-definitions.html#typical.data">data</a>, <a href="#proto_library.allow_exports">allow_exports</a>, <a href="common-definitions.html#common.compatible_with">compatible_with</a>, <a href="common-definitions.html#common.deprecation">deprecation</a>, <a href="common-definitions.html#common.distribs">distribs</a>, <a href="common-definitions.html#common.exec_compatible_with">exec_compatible_with</a>, <a href="common-definitions.html#common.exec_properties">exec_properties</a>, <a href="#proto_library.exports">exports</a>, <a href="common-definitions.html#common.features">features</a>, <a href="#proto_library.import_prefix">import_prefix</a>, <a href="common-definitions.html#typical.licenses">licenses</a>, <a href="common-definitions.html#common.restricted_to">restricted_to</a>, <a href="#proto_library.strip_import_prefix">strip_import_prefix</a>, <a href="common-definitions.html#common.tags">tags</a>, <a href="common-definitions.html#common.target_compatible_with">target_compatible_with</a>, <a href="common-definitions.html#common.testonly">testonly</a>, <a href="common-definitions.html#common.visibility">visibility</a>)</pre>


	<p>Deprecated. Please use <a href="https://github.com/bazelbuild/rules_proto">
	https://github.com/bazelbuild/rules_proto</a> instead.
	</p>

	<p>Use <code>proto_library</code> to define libraries of protocol buffers
	which may be used from multiple languages. A <code>proto_library</code> may be listed
	in the <code>deps</code> clause of supported rules, such as <code>java_proto_library</code>.
	</p>

	<p>When compiled on the command-line, a <code>proto_library</code> creates a file named
	<code>foo-descriptor-set.proto.bin</code>, which is the descriptor set for the
	messages the rule srcs. The file is a serialized <code>FileDescriptorSet</code>, which is
	described in
	<a href="https://developers.google.com/protocol-buffers/docs/techniques#self-description">
	https://developers.google.com/protocol-buffers/docs/techniques#self-description</a>.
	</p>

	<p>It only contains information about the <code>.proto</code> files directly mentioned by a
	<code>proto_library</code> rule; the collection of transitive descriptor sets is available through
	the <code>[ProtoInfo].transitive_descriptor_sets</code> Starlark provider.
	See documentation in <code>ProtoInfo.java</code>.</p>

	<p>Recommended code organization:</p>

	<ul>
	<li> One <code>proto_library</code> rule per <code>.proto</code> file.
	<li> A file named <code>foo.proto</code> will be in a rule named <code>foo_proto</code>, which
	is located in the same package.
	<li> A <code>[language]_proto_library</code> that wraps a <code>proto_library</code> named
	<code>foo_proto</code> should be called
	<code>foo_[language]_proto</code>, and be located in the same package.
	</ul>



	<h3 id="proto_library_args">Arguments</h3>
	<table class="table table-condensed table-bordered table-params">
	<colgroup>
	<col class="col-param" />
	<col class="param-description" />
	</colgroup>
	<thead>
	<tr>
	<th colspan="2">Attributes</th>
	</tr>
	</thead>
	<tbody>
	<tr>
	<td id="proto_library.name"><code>name</code></td>
	<td>
	<p><a href="/versions/7.1.0/concepts/labels#target-names">Name</a>; required</p>
	<p>A unique name for this target.</p>

	</td>
	</tr>
	<tr>
	<td id="proto_library.deps">
	<code>deps</code>
	</td>
	<td>
	<p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
	The list of other <code>proto_library</code> rules that the target depends upon.
	A <code>proto_library</code> may only depend on other
	<code>proto_library</code> targets.
	It may not depend on language-specific libraries.

	</td>
	</tr>
	<tr>
	<td id="proto_library.srcs">
	<code>srcs</code>
	</td>
	<td>
	<p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
	The list of <code>.proto</code> and <code>.protodevel</code> files that are
	processed to create the target. This is usually a non empty list. One usecase
	where <code>srcs</code> can be empty is an <i>alias-library</i>. This is a
	proto_library rule having one or more other proto_library in <code>deps</code>.
	This pattern can be used to e.g. export a public api under a persistent name.

	</td>
	</tr>
	<tr>
	<td id="proto_library.allow_exports">
	<code>allow_exports</code>
	</td>
	<td>
	<p><a href="/versions/7.1.0/concepts/labels">Label</a>; default is <code>None</code></p>
	An optional allowlist that prevents proto library to be reexported or used in
	lang_proto_library that is not in one of the listed packages.

	</td>
	</tr>
	<tr>
	<td id="proto_library.exports">
	<code>exports</code>
	</td>
	<td>
	<p>List of <a href="/versions/7.1.0/concepts/labels">labels</a>; default is <code>[]</code></p>
	List of proto_library targets that can be referenced via "import public" in the proto
	source.

	</td>
	</tr>
	<tr>
	<td id="proto_library.import_prefix">
	<code>import_prefix</code>
	</td>
	<td>
	<p>String; default is <code>""</code></p>
	The prefix to add to the paths of the .proto files in this rule.

	<p>When set, the .proto source files in the <code>srcs</code> attribute of this rule are
	accessible at is the value of this attribute prepended to their repository-relative path.

	<p>The prefix in the <code>strip_import_prefix</code> attribute is removed before this
	prefix is added.

	</td>
	</tr>
	<tr>
	<td id="proto_library.strip_import_prefix">
	<code>strip_import_prefix</code>
	</td>
	<td>
	<p>String; default is <code>""</code></p>
	The prefix to strip from the paths of the .proto files in this rule.

	<p>When set, .proto source files in the <code>srcs</code> attribute of this rule are
	accessible at their path with this prefix cut off.

	<p>If it's a relative path (not starting with a slash), it's taken as a package-relative
	one. If it's an absolute one, it's understood as a repository-relative path.

	<p>The prefix in the <code>import_prefix</code> attribute is added after this prefix is
	stripped.

	</td>
	</tr>
	</tbody>
	</table>

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