Support loading http credentials from netrc (#2623)

Bazel's `http_archive` and `http_file` use `~/.netrc` file to load HTTP
credentials.

Now rules_rust use the same approach if no other authorization
parameters are provided.

NOTE: `http_archive` supports passing a custom `netrc` and
`auth_patterns`. But this parameters are not added to the rust rules at
the moment.

---------

Co-authored-by: Daniel Wagner-Hall <[email protected]>

docs/flatten.md

@@ -1293,10 +1293,10 @@ Generates a toolchain-bearing repository that declares the toolchains from some
 ## rust_toolchain_tools_repository
 
 <pre>
-rust_toolchain_tools_repository(<a href="#rust_toolchain_tools_repository-name">name</a>, <a href="#rust_toolchain_tools_repository-allocator_library">allocator_library</a>, <a href="#rust_toolchain_tools_repository-auth">auth</a>, <a href="#rust_toolchain_tools_repository-dev_components">dev_components</a>, <a href="#rust_toolchain_tools_repository-edition">edition</a>, <a href="#rust_toolchain_tools_repository-exec_triple">exec_triple</a>,
-                                <a href="#rust_toolchain_tools_repository-extra_exec_rustc_flags">extra_exec_rustc_flags</a>, <a href="#rust_toolchain_tools_repository-extra_rustc_flags">extra_rustc_flags</a>, <a href="#rust_toolchain_tools_repository-global_allocator_library">global_allocator_library</a>,
-                                <a href="#rust_toolchain_tools_repository-iso_date">iso_date</a>, <a href="#rust_toolchain_tools_repository-opt_level">opt_level</a>, <a href="#rust_toolchain_tools_repository-repo_mapping">repo_mapping</a>, <a href="#rust_toolchain_tools_repository-rustfmt_version">rustfmt_version</a>, <a href="#rust_toolchain_tools_repository-sha256s">sha256s</a>,
-                                <a href="#rust_toolchain_tools_repository-target_triple">target_triple</a>, <a href="#rust_toolchain_tools_repository-urls">urls</a>, <a href="#rust_toolchain_tools_repository-version">version</a>)
+rust_toolchain_tools_repository(<a href="#rust_toolchain_tools_repository-name">name</a>, <a href="#rust_toolchain_tools_repository-allocator_library">allocator_library</a>, <a href="#rust_toolchain_tools_repository-auth">auth</a>, <a href="#rust_toolchain_tools_repository-auth_patterns">auth_patterns</a>, <a href="#rust_toolchain_tools_repository-dev_components">dev_components</a>,
+                                <a href="#rust_toolchain_tools_repository-edition">edition</a>, <a href="#rust_toolchain_tools_repository-exec_triple">exec_triple</a>, <a href="#rust_toolchain_tools_repository-extra_exec_rustc_flags">extra_exec_rustc_flags</a>, <a href="#rust_toolchain_tools_repository-extra_rustc_flags">extra_rustc_flags</a>,
+                                <a href="#rust_toolchain_tools_repository-global_allocator_library">global_allocator_library</a>, <a href="#rust_toolchain_tools_repository-iso_date">iso_date</a>, <a href="#rust_toolchain_tools_repository-netrc">netrc</a>, <a href="#rust_toolchain_tools_repository-opt_level">opt_level</a>, <a href="#rust_toolchain_tools_repository-repo_mapping">repo_mapping</a>,
+                                <a href="#rust_toolchain_tools_repository-rustfmt_version">rustfmt_version</a>, <a href="#rust_toolchain_tools_repository-sha256s">sha256s</a>, <a href="#rust_toolchain_tools_repository-target_triple">target_triple</a>, <a href="#rust_toolchain_tools_repository-urls">urls</a>, <a href="#rust_toolchain_tools_repository-version">version</a>)
 </pre>
 
 Composes a single workspace containing the toolchain components for compiling on a given platform to a series of target platforms.
@@ -1311,13 +1311,15 @@ A given instance of this rule should be accompanied by a toolchain_repository_pr
 | <a id="rust_toolchain_tools_repository-name"></a>name |  A unique name for this repository.   | <a href="https://bazel.build/concepts/labels#target-names">Name</a> | required |  |
 | <a id="rust_toolchain_tools_repository-allocator_library"></a>allocator_library |  Target that provides allocator functions when rust_library targets are embedded in a cc_binary.   | String | optional | <code>"@rules_rust//ffi/cc/allocator_library"</code> |
 | <a id="rust_toolchain_tools_repository-auth"></a>auth |  Auth object compatible with repository_ctx.download to use when downloading files. See [repository_ctx.download](https://docs.bazel.build/versions/main/skylark/lib/repository_ctx.html#download) for more details.   | <a href="https://bazel.build/rules/lib/dict">Dictionary: String -> String</a> | optional | <code>{}</code> |
+| <a id="rust_toolchain_tools_repository-auth_patterns"></a>auth_patterns |  A list of patterns to match against urls for which the auth object should be used.   | List of strings | optional | <code>[]</code> |
 | <a id="rust_toolchain_tools_repository-dev_components"></a>dev_components |  Whether to download the rustc-dev components (defaults to False). Requires version to be "nightly".   | Boolean | optional | <code>False</code> |
 | <a id="rust_toolchain_tools_repository-edition"></a>edition |  The rust edition to be used by default (2015, 2018, or 2021). If absent, every rule is required to specify its <code>edition</code> attribute.   | String | optional | <code>""</code> |
 | <a id="rust_toolchain_tools_repository-exec_triple"></a>exec_triple |  The Rust-style target that this compiler runs on   | String | required |  |
 | <a id="rust_toolchain_tools_repository-extra_exec_rustc_flags"></a>extra_exec_rustc_flags |  Extra flags to pass to rustc in exec configuration   | List of strings | optional | <code>[]</code> |
 | <a id="rust_toolchain_tools_repository-extra_rustc_flags"></a>extra_rustc_flags |  Extra flags to pass to rustc in non-exec configuration   | List of strings | optional | <code>[]</code> |
 | <a id="rust_toolchain_tools_repository-global_allocator_library"></a>global_allocator_library |  Target that provides allocator functions when a global allocator is used with cc_common.link.   | String | optional | <code>"@rules_rust//ffi/cc/global_allocator_library"</code> |
 | <a id="rust_toolchain_tools_repository-iso_date"></a>iso_date |  The date of the tool (or None, if the version is a specific version).   | String | optional | <code>""</code> |
+| <a id="rust_toolchain_tools_repository-netrc"></a>netrc |  .netrc file to use for authentication; mirrors the eponymous attribute from http_archive   | String | optional | <code>""</code> |
 | <a id="rust_toolchain_tools_repository-opt_level"></a>opt_level |  Rustc optimization levels. For more details see the documentation for <code>rust_toolchain.opt_level</code>.   | <a href="https://bazel.build/rules/lib/dict">Dictionary: String -> String</a> | optional | <code>{}</code> |
 | <a id="rust_toolchain_tools_repository-repo_mapping"></a>repo_mapping |  A dictionary from local repository name to global repository name. This allows controls over workspace dependency resolution for dependencies of this repository.&lt;p&gt;For example, an entry <code>"@foo": "@bar"</code> declares that, for any time this repository depends on <code>@foo</code> (such as a dependency on <code>@foo//some:target</code>, it should actually resolve that dependency within globally-declared <code>@bar</code> (<code>@bar//some:target</code>).   | <a href="https://bazel.build/rules/lib/dict">Dictionary: String -> String</a> | required |  |
 | <a id="rust_toolchain_tools_repository-rustfmt_version"></a>rustfmt_version |  The version of the tool among "nightly", "beta", or an exact version.   | String | optional | <code>""</code> |
@@ -1725,7 +1727,7 @@ Dependencies used in the implementation of `rules_rust`.
 
 <pre>
 rust_analyzer_toolchain_repository(<a href="#rust_analyzer_toolchain_repository-name">name</a>, <a href="#rust_analyzer_toolchain_repository-version">version</a>, <a href="#rust_analyzer_toolchain_repository-exec_compatible_with">exec_compatible_with</a>, <a href="#rust_analyzer_toolchain_repository-target_compatible_with">target_compatible_with</a>,
-                                   <a href="#rust_analyzer_toolchain_repository-iso_date">iso_date</a>, <a href="#rust_analyzer_toolchain_repository-sha256s">sha256s</a>, <a href="#rust_analyzer_toolchain_repository-urls">urls</a>, <a href="#rust_analyzer_toolchain_repository-auth">auth</a>)
+                                   <a href="#rust_analyzer_toolchain_repository-iso_date">iso_date</a>, <a href="#rust_analyzer_toolchain_repository-sha256s">sha256s</a>, <a href="#rust_analyzer_toolchain_repository-urls">urls</a>, <a href="#rust_analyzer_toolchain_repository-auth">auth</a>, <a href="#rust_analyzer_toolchain_repository-netrc">netrc</a>, <a href="#rust_analyzer_toolchain_repository-auth_patterns">auth_patterns</a>)
 </pre>
 
 Assemble a remote rust_analyzer_toolchain target based on the given params.
@@ -1743,6 +1745,8 @@ Assemble a remote rust_analyzer_toolchain target based on the given params.
 | <a id="rust_analyzer_toolchain_repository-sha256s"></a>sha256s |  A dict associating tool subdirectories to sha256 hashes. See [rust_register_toolchains](#rust_register_toolchains) for more details.   |  `None` |
 | <a id="rust_analyzer_toolchain_repository-urls"></a>urls |  A list of mirror urls containing the tools from the Rust-lang static file server. These must contain the '{}' used to substitute the tool being fetched (using .format). Defaults to ['https://static.rust-lang.org/dist/{}.tar.xz']   |  `None` |
 | <a id="rust_analyzer_toolchain_repository-auth"></a>auth |  Auth object compatible with repository_ctx.download to use when downloading files. See [repository_ctx.download](https://docs.bazel.build/versions/main/skylark/lib/repository_ctx.html#download) for more details.   |  `None` |
+| <a id="rust_analyzer_toolchain_repository-netrc"></a>netrc |  .netrc file to use for authentication; mirrors the eponymous attribute from http_archive   |  `None` |
+| <a id="rust_analyzer_toolchain_repository-auth_patterns"></a>auth_patterns |  Override mapping of hostnames to authorization patterns; mirrors the eponymous attribute from http_archive   |  `None` |
 
 **RETURNS**
 
@@ -1996,8 +2000,8 @@ rust_repositories(<a href="#rust_repositories-kwargs">kwargs</a>)
 rust_repository_set(<a href="#rust_repository_set-name">name</a>, <a href="#rust_repository_set-exec_triple">exec_triple</a>, <a href="#rust_repository_set-target_settings">target_settings</a>, <a href="#rust_repository_set-version">version</a>, <a href="#rust_repository_set-versions">versions</a>, <a href="#rust_repository_set-allocator_library">allocator_library</a>,
                     <a href="#rust_repository_set-global_allocator_library">global_allocator_library</a>, <a href="#rust_repository_set-extra_target_triples">extra_target_triples</a>, <a href="#rust_repository_set-iso_date">iso_date</a>, <a href="#rust_repository_set-rustfmt_version">rustfmt_version</a>,
                     <a href="#rust_repository_set-edition">edition</a>, <a href="#rust_repository_set-dev_components">dev_components</a>, <a href="#rust_repository_set-extra_rustc_flags">extra_rustc_flags</a>, <a href="#rust_repository_set-extra_exec_rustc_flags">extra_exec_rustc_flags</a>, <a href="#rust_repository_set-opt_level">opt_level</a>,
-                    <a href="#rust_repository_set-sha256s">sha256s</a>, <a href="#rust_repository_set-urls">urls</a>, <a href="#rust_repository_set-auth">auth</a>, <a href="#rust_repository_set-register_toolchain">register_toolchain</a>, <a href="#rust_repository_set-exec_compatible_with">exec_compatible_with</a>,
-                    <a href="#rust_repository_set-default_target_compatible_with">default_target_compatible_with</a>)
+                    <a href="#rust_repository_set-sha256s">sha256s</a>, <a href="#rust_repository_set-urls">urls</a>, <a href="#rust_repository_set-auth">auth</a>, <a href="#rust_repository_set-netrc">netrc</a>, <a href="#rust_repository_set-auth_patterns">auth_patterns</a>, <a href="#rust_repository_set-register_toolchain">register_toolchain</a>,
+                    <a href="#rust_repository_set-exec_compatible_with">exec_compatible_with</a>, <a href="#rust_repository_set-default_target_compatible_with">default_target_compatible_with</a>)
 </pre>
 
 Assembles a remote repository for the given toolchain params, produces a proxy repository     to contain the toolchain declaration, and registers the toolchains.
@@ -2025,6 +2029,8 @@ Assembles a remote repository for the given toolchain params, produces a proxy r
 | <a id="rust_repository_set-sha256s"></a>sha256s |  A dict associating tool subdirectories to sha256 hashes. See [rust_register_toolchains](#rust_register_toolchains) for more details.   |  `None` |
 | <a id="rust_repository_set-urls"></a>urls |  A list of mirror urls containing the tools from the Rust-lang static file server. These must contain the '{}' used to substitute the tool being fetched (using .format).   |  `["https://static.rust-lang.org/dist/{}.tar.xz"]` |
 | <a id="rust_repository_set-auth"></a>auth |  Auth object compatible with repository_ctx.download to use when downloading files. See [repository_ctx.download](https://docs.bazel.build/versions/main/skylark/lib/repository_ctx.html#download) for more details.   |  `None` |
+| <a id="rust_repository_set-netrc"></a>netrc |  .netrc file to use for authentication; mirrors the eponymous attribute from http_archive   |  `None` |
+| <a id="rust_repository_set-auth_patterns"></a>auth_patterns |  Override mapping of hostnames to authorization patterns; mirrors the eponymous attribute from http_archive   |  `None` |
 | <a id="rust_repository_set-register_toolchain"></a>register_toolchain |  If True, the generated <code>rust_toolchain</code> target will become a registered toolchain.   |  `True` |
 | <a id="rust_repository_set-exec_compatible_with"></a>exec_compatible_with |  A list of constraints for the execution platform for this toolchain.   |  `None` |
 | <a id="rust_repository_set-default_target_compatible_with"></a>default_target_compatible_with |  A list of constraints for the target platform for this toolchain when the exec platform is the same as the target platform.   |  `None` |
@@ -2103,7 +2109,7 @@ rust_toolchain_repository(<a href="#rust_toolchain_repository-name">name</a>, <a
                           <a href="#rust_toolchain_repository-target_compatible_with">target_compatible_with</a>, <a href="#rust_toolchain_repository-target_settings">target_settings</a>, <a href="#rust_toolchain_repository-channel">channel</a>, <a href="#rust_toolchain_repository-allocator_library">allocator_library</a>,
                           <a href="#rust_toolchain_repository-global_allocator_library">global_allocator_library</a>, <a href="#rust_toolchain_repository-iso_date">iso_date</a>, <a href="#rust_toolchain_repository-rustfmt_version">rustfmt_version</a>, <a href="#rust_toolchain_repository-edition">edition</a>,
                           <a href="#rust_toolchain_repository-dev_components">dev_components</a>, <a href="#rust_toolchain_repository-extra_rustc_flags">extra_rustc_flags</a>, <a href="#rust_toolchain_repository-extra_exec_rustc_flags">extra_exec_rustc_flags</a>, <a href="#rust_toolchain_repository-opt_level">opt_level</a>,
-                          <a href="#rust_toolchain_repository-sha256s">sha256s</a>, <a href="#rust_toolchain_repository-urls">urls</a>, <a href="#rust_toolchain_repository-auth">auth</a>)
+                          <a href="#rust_toolchain_repository-sha256s">sha256s</a>, <a href="#rust_toolchain_repository-urls">urls</a>, <a href="#rust_toolchain_repository-auth">auth</a>, <a href="#rust_toolchain_repository-netrc">netrc</a>, <a href="#rust_toolchain_repository-auth_patterns">auth_patterns</a>)
 </pre>
 
 Assembles a remote repository for the given toolchain params, produces a proxy repository     to contain the toolchain declaration, and registers the toolchains.
@@ -2133,6 +2139,8 @@ Assembles a remote repository for the given toolchain params, produces a proxy r
 | <a id="rust_toolchain_repository-sha256s"></a>sha256s |  A dict associating tool subdirectories to sha256 hashes. See [rust_register_toolchains](#rust_register_toolchains) for more details.   |  `None` |
 | <a id="rust_toolchain_repository-urls"></a>urls |  A list of mirror urls containing the tools from the Rust-lang static file server. These must contain the '{}' used to substitute the tool being fetched (using .format). Defaults to ['https://static.rust-lang.org/dist/{}.tar.xz']   |  `["https://static.rust-lang.org/dist/{}.tar.xz"]` |
 | <a id="rust_toolchain_repository-auth"></a>auth |  Auth object compatible with repository_ctx.download to use when downloading files. See [repository_ctx.download](https://docs.bazel.build/versions/main/skylark/lib/repository_ctx.html#download) for more details.   |  `None` |
+| <a id="rust_toolchain_repository-netrc"></a>netrc |  .netrc file to use for authentication; mirrors the eponymous attribute from http_archive   |  `None` |
+| <a id="rust_toolchain_repository-auth_patterns"></a>auth_patterns |  A list of patterns to match against urls for which the auth object should be used.   |  `None` |
 
 **RETURNS**