Add a new compiler tool which can be used to compile CEL expressions and policies using serialized environment

common/env/env.go

@@ -836,7 +836,7 @@ func (td *TypeDesc) AsCELType(tp types.Provider) (*types.Type, error) {
 	}
 }
 
-// SerializeTypeDesc converts *types.Type to a serialized format TypeDesc
+// SerializeTypeDesc converts a CEL native *types.Type to a serializable TypeDesc.
 func SerializeTypeDesc(t *types.Type) *TypeDesc {
 	typeName := t.TypeName()
 	if t.Kind() == types.TypeParamKind {

ext/extension_option_factory_test.go

@@ -61,6 +61,9 @@ func TestExtensionOptionFactoryValidBindingsExtension(t *testing.T) {
 		t.Fatalf("ExtensionOptionFactory(%s) returned invalid extension", e.Name)
 	}
 	cfg, err := en.ToConfig("test config")
+	if err != nil {
+		t.Fatalf("ToConfig(%s) returned error: %v", e.Name, err)
+	}
 	if len(cfg.Extensions) != 1 || cfg.Extensions[0].Name != "cel.lib.ext.cel.bindings" || cfg.Extensions[0].Version != "latest" {
 		t.Fatalf("ExtensionOptionFactory(%s) returned invalid extension", e.Name)
 	}

policy/testdata/k8s/config.yaml

@@ -14,6 +14,10 @@
 
 name: k8s
 extensions:
+  - name: "optional"
+    version: "latest"
+  - name: "bindings"
+    version: "latest"
   - name: "strings"
     version: 2
 variables:

tools/compiler/BUILD.bazel

@@ -0,0 +1,67 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+package(
+    default_visibility = ["//visibility:public"],
+    licenses = ["notice"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "compiler.go",
+    ],
+    importpath = "github.com/google/cel-go/tools/compiler",
+    deps = [
+        "//cel:go_default_library",
+        "//common:go_default_library",
+        "//common/env:go_default_library",
+        "//common/types:go_default_library",
+        "//ext:go_default_library",
+        "//policy:go_default_library",
+        "@dev_cel_expr//:expr",
+        "@dev_cel_expr//conformance:go_default_library",
+        "@in_gopkg_yaml_v3//:go_default_library",
+        "@io_bazel_rules_go//go/runfiles",
+        "@org_golang_google_genproto_googleapis_api//expr/v1alpha1:go_default_library",
+        "@org_golang_google_protobuf//encoding/prototext:go_default_library",
+        "@org_golang_google_protobuf//proto:go_default_library",
+        "@org_golang_google_protobuf//reflect/protoreflect:go_default_library",
+        "@org_golang_google_protobuf//types/descriptorpb:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    size = "small",
+    srcs = [
+        "compiler_test.go",
+    ],
+    data = glob(["testdata/**"]),
+    embed = [":go_default_library"],
+    deps = [
+        "//cel:go_default_library",
+        "//common/decls:go_default_library",
+        "//common/env:go_default_library",
+        "//common/types:go_default_library",
+        "//ext:go_default_library",
+        "//policy:go_default_library",
+        "@dev_cel_expr//:expr",
+        "@dev_cel_expr//conformance:go_default_library",
+        "@in_gopkg_yaml_v3//:go_default_library",
+        "@org_golang_google_protobuf//types/known/structpb:go_default_library",
+    ],
+)