From b21f2e30815a66d96c711f4739b18e7a56e522db Mon Sep 17 00:00:00 2001
From: Charlie Marsh <charliemarsh@openai.com>
Date: Wed, 2 Sep 2026 01:42:03 +0000
Subject: [PATCH] Add a cacheable Bazel app-server schema bundle (#42174)

## What changed

- Add a `schema_bundle` rule that generates stable and experimental app-server
  schema directories as declared Bazel actions.
- Include the pinned `zstd` executable in the bundle so consumers can normalize
  generated JSON without a separate `bazel run` invocation.
- Expose the app-server protocol test binary as the schema generator and add the
  manual `//bazel/schema:public-schema-bundle` target.

GitOrigin-RevId: 0a7ce47258d297dbf20db78626f2843145ee1b49
---
 bazel/rules/BUILD.bazel                  |  1 +
 bazel/rules/schema_bundle.bzl            | 39 ++++++++++++++++++++++++
 bazel/schema/BUILD.bazel                 |  8 +++++
 codex-rs/app-server-protocol/BUILD.bazel |  8 +++++
 4 files changed, 56 insertions(+)
 create mode 100644 bazel/rules/schema_bundle.bzl
 create mode 100644 bazel/schema/BUILD.bazel

diff --git a/bazel/rules/BUILD.bazel b/bazel/rules/BUILD.bazel
index 218872c73c..ab6d1f9763 100644
--- a/bazel/rules/BUILD.bazel
+++ b/bazel/rules/BUILD.bazel
@@ -2,4 +2,5 @@ package(default_visibility = ["//visibility:public"])
 
 exports_files([
     "e2e_benchmark.bzl",
+    "schema_bundle.bzl",
 ])
diff --git a/bazel/rules/schema_bundle.bzl b/bazel/rules/schema_bundle.bzl
new file mode 100644
index 0000000000..5f8e2eae01
--- /dev/null
+++ b/bazel/rules/schema_bundle.bzl
@@ -0,0 +1,39 @@
+"""Cache schema generation from the filtered public Rust test executable."""
+
+def _schema_bundle_impl(ctx):
+    outputs = []
+    for mode in ["stable", "experimental"]:
+        schema = ctx.actions.declare_directory(ctx.label.name + "." + mode)
+        ctx.actions.run(
+            executable = ctx.executable.generator,
+            tools = [ctx.attr.generator[DefaultInfo].files_to_run],
+            arguments = [
+                "--exact",
+                "--ignored",
+                "schema_fixtures_tests::write_schema_fixtures_from_env",
+            ],
+            env = {
+                "CODEX_APP_SERVER_SCHEMA_ROOT": schema.path,
+                "CODEX_APP_SERVER_SCHEMA_EXPERIMENTAL": "1" if mode == "experimental" else "0",
+                "RUST_MIN_STACK": "8388608",
+            },
+            outputs = [schema],
+            mnemonic = "PublicSchema",
+            progress_message = "Generating %s public app-server schemas" % mode,
+        )
+        outputs.append(schema)
+
+    # Expose the pinned compressor alongside the cached directories so callers
+    # can normalize the JSON without a separate `bazel run` invocation.
+    zstd = ctx.actions.declare_file(ctx.label.name + ".zstd")
+    ctx.actions.symlink(output = zstd, target_file = ctx.executable.zstd, is_executable = True)
+    return [DefaultInfo(files = depset(outputs + [zstd]))]
+
+schema_bundle = rule(
+    implementation = _schema_bundle_impl,
+    attrs = {
+        "generator": attr.label(mandatory = True, executable = True, cfg = "exec"),
+        "zstd": attr.label(default = "@zstd//:zstd_cli", executable = True, cfg = "exec"),
+    },
+    doc = "Generates both schema modes as cacheable actions with explicit tool dependencies.",
+)
diff --git a/bazel/schema/BUILD.bazel b/bazel/schema/BUILD.bazel
new file mode 100644
index 0000000000..401d30b00f
--- /dev/null
+++ b/bazel/schema/BUILD.bazel
@@ -0,0 +1,8 @@
+load("//bazel/rules:schema_bundle.bzl", "schema_bundle")
+
+schema_bundle(
+    name = "public-schema-bundle",
+    testonly = True,
+    generator = "//codex-rs/app-server-protocol:schema-generator",
+    tags = ["manual"],
+)
diff --git a/codex-rs/app-server-protocol/BUILD.bazel b/codex-rs/app-server-protocol/BUILD.bazel
index eb6e1d280a..4ecf754479 100644
--- a/codex-rs/app-server-protocol/BUILD.bazel
+++ b/codex-rs/app-server-protocol/BUILD.bazel
@@ -9,3 +9,11 @@ codex_rust_crate(
         allow_empty = True,
     ),
 )
+
+alias(
+    name = "schema-generator",
+    testonly = True,
+    actual = ":app-server-protocol-unit-tests-bin",
+    tags = ["manual"],
+    visibility = ["//bazel/schema:__pkg__"],
+)