Support relocatable rpmbuild by adding data attribute to the toolchain

rpmbuild ships with runtime configuration files (lib/rpm/) that must be
present for it to successfully build RPMs. When running under remote
execution, these files were not being staged because the toolchain had
no way to declare them as dependencies.

Add a `data` attribute to `rpmbuild_toolchain` so that runtime files
can be specified alongside the rpmbuild binary. These files are
propagated through `RpmbuildInfo` and included as inputs to the MakeRpm
action in `pkg_rpm`.

Author: reutermj

pkg/rpm_pfg.bzl

@@ -475,6 +475,7 @@ def _pkg_rpm_impl(ctx):
 
     files = []
     tools = []
+    toolchain_data = []
     debuginfo_type = DEBUGINFO_TYPE_NONE
     name = ctx.attr.package_name if ctx.attr.package_name else ctx.label.name
     rpm_ctx.make_rpm_args.append("--name=" + name)
@@ -500,6 +501,8 @@ def _pkg_rpm_impl(ctx):
             tools.append(executable_files)
             rpm_ctx.make_rpm_args.append("--rpmbuild=%s" % executable_files.executable.path)
 
+        toolchain_data = toolchain.data
+
         if ctx.attr.debuginfo:
             debuginfo_type = toolchain.debuginfo_type
             rpm_ctx.make_rpm_args.append("--debuginfo_type=%s" % debuginfo_type)
@@ -885,7 +888,7 @@ def _pkg_rpm_impl(ctx):
         executable = ctx.executable._make_rpm,
         use_default_shell_env = True,
         arguments = rpm_ctx.make_rpm_args,
-        inputs = files + (ctx.files.data or []),
+        inputs = files + (ctx.files.data or []) + toolchain_data,
         outputs = rpm_ctx.output_rpm_files,
         env = {
             "LANG": "en_US.UTF-8",

tests/rpm/toolchain_tests.bzl

@@ -53,6 +53,11 @@ def _toolchain_contents_test_impl(ctx):
         ctx.attr.expect_path,
         info.path,
     )
+    asserts.equals(
+        env,
+        ctx.attr.expect_data_count,
+        len(info.data),
+    )
     return analysistest.end(env)
 
 toolchain_contents_test = analysistest.make(
@@ -65,6 +70,7 @@ toolchain_contents_test = analysistest.make(
             allow_files = True,
         ),
         "expect_path": attr.string(),
+        "expect_data_count": attr.int(default = 0),
     },
 )
 
@@ -119,6 +125,21 @@ def _create_toolchain_creation_tests():
         expect_path = "/usr/bin/foo",
     )
 
+    rpmbuild_toolchain(
+        name = "tc_with_data",
+        path = "/usr/bin/foo",
+        data = [":toolchain_test.bzl"],
+        tags = ["manual"],
+    )
+    toolchain_contents_test(
+        name = "tc_with_data_test",
+        target_under_test = ":tc_with_data",
+        expect_valid = True,
+        expect_label = None,
+        expect_path = "/usr/bin/foo",
+        expect_data_count = 1,
+    )
+
 # buildifier: disable=unnamed-macro
 def create_toolchain_analysis_tests():
     _create_toolchain_creation_tests()

toolchains/rpm/rpmbuild.bzl

@@ -22,6 +22,7 @@ RpmbuildInfo = provider(
         "path": "The path to a pre-built rpmbuild",
         "version": "The version string of rpmbuild",
         "debuginfo_type": "The variant of the underlying debuginfo config",
+        "data": "Additional files needed at runtime by rpmbuild",
     },
 )
 
@@ -37,6 +38,7 @@ def _rpmbuild_toolchain_impl(ctx):
             path = ctx.attr.path,
             version = ctx.attr.version,
             debuginfo_type = ctx.attr.debuginfo_type,
+            data = ctx.files.data,
         ),
     )
     return [toolchain_info]
@@ -64,6 +66,10 @@ rpmbuild_toolchain = rule(
             """,
             default = "none",
         ),
+        "data": attr.label_list(
+            doc = "Additional files needed at runtime by rpmbuild.",
+            allow_files = True,
+        ),
     },
 )