Add YAML validation for configuration files.

For validation, the "on" key in existing YAML files is changed to a literal
string. In the YAML spec, on is a keyword which encodes a boolean value, so
without relying on a specific implementation the YAML files are technically
not encoding an object that complies with the specification.

PiperOrigin-RevId: 350172147

1 files changed, 41 insertions, 0 deletions

diff --git a/tools/yamltest/defs.bzl b/tools/yamltest/defs.bzl
new file mode 100644
index 000000000..fd04f947d
--- /dev/null
+++ b/tools/yamltest/defs.bzl
@@ -0,0 +1,41 @@
+"""Tools for testing yaml files against schemas."""
+
+def _yaml_test_impl(ctx):
+    """Implementation for yaml_test."""
+    runner = ctx.actions.declare_file(ctx.label.name)
+    ctx.actions.write(runner, "\n".join([
+        "#!/bin/bash",
+        "set -euo pipefail",
+        "%s -schema=%s -- %s" % (
+            ctx.files._tool[0].short_path,
+            ctx.files.schema[0].short_path,
+            " ".join([f.short_path for f in ctx.files.srcs]),
+        ),
+    ]), is_executable = True)
+    return [DefaultInfo(
+        runfiles = ctx.runfiles(files = ctx.files._tool + ctx.files.schema + ctx.files.srcs),
+        executable = runner,
+    )]
+
+yaml_test = rule(
+    implementation = _yaml_test_impl,
+    doc = "Tests a yaml file against a schema.",
+    attrs = {
+        "srcs": attr.label_list(
+            doc = "The input yaml files.",
+            mandatory = True,
+            allow_files = True,
+        ),
+        "schema": attr.label(
+            doc = "The schema file in JSON schema format.",
+            allow_single_file = True,
+            mandatory = True,
+        ),
+        "_tool": attr.label(
+            executable = True,
+            cfg = "host",
+            default = Label("//tools/yamltest:yamltest"),
+        ),
+    },
+    test = True,
+)