Merge pull request #23553 from michaelywg/cel_stub_activation

Create stub version of CEL Activation

BUILD

@@ -1860,6 +1860,8 @@ grpc_cc_library(
     ],
     hdrs = [
         "src/core/lib/security/authorization/authorization_engine.h",
+        "src/core/lib/security/authorization/mock_cel/activation.h",
+        "src/core/lib/security/authorization/mock_cel/cel_value.h",
     ],
     language = "c++",
     deps = [

build_autogenerated.yaml

@@ -4777,6 +4777,8 @@ targets:
   language: c++
   headers:
   - src/core/lib/security/authorization/authorization_engine.h
+  - src/core/lib/security/authorization/mock_cel/activation.h
+  - src/core/lib/security/authorization/mock_cel/cel_value.h
   src:
   - src/core/lib/security/authorization/authorization_engine.cc
   - test/core/security/authorization_engine_test.cc

src/core/lib/security/authorization/mock_cel/activation.h

@@ -0,0 +1,61 @@
+// Copyright 2020 gRPC authors.
+//
+// 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
+//
+//     http://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.
+
+#ifndef GRPC_CORE_LIB_SECURITY_AUTHORIZATION_MOCK_CEL_ACTIVATION_H
+#define GRPC_CORE_LIB_SECURITY_AUTHORIZATION_MOCK_CEL_ACTIVATION_H
+
+#include <grpc/support/port_platform.h>
+
+#include "absl/strings/string_view.h"
+
+#include "src/core/lib/security/authorization/mock_cel/cel_value.h"
+
+namespace google {
+namespace api {
+namespace expr {
+namespace runtime {
+
+// Base class for an activation. This is a temporary stub implementation of CEL
+// APIs. Once gRPC imports the CEL library, this class will be removed.
+class BaseActivation {
+ public:
+  BaseActivation() = default;
+
+  // Non-copyable/non-assignable
+  BaseActivation(const BaseActivation&) = delete;
+  BaseActivation& operator=(const BaseActivation&) = delete;
+};
+
+// Instance of Activation class is used by evaluator.
+// It provides binding between references used in expressions
+// and actual values. This is a temporary stub implementation of CEL APIs.
+// Once gRPC imports the CEL library, this class will be removed.
+class Activation : public BaseActivation {
+ public:
+  Activation() = default;
+
+  // Non-copyable/non-assignable
+  Activation(const Activation&) = delete;
+  Activation& operator=(const Activation&) = delete;
+
+  // Insert value into Activation.
+  void InsertValue(absl::string_view name, const CelValue& value) {}
+};
+
+}  // namespace runtime
+}  // namespace expr
+}  // namespace api
+}  // namespace google
+
+#endif  // GRPC_CORE_LIB_SECURITY_AUTHORIZATION_MOCK_CEL_ACTIVATION_H

src/core/lib/security/authorization/mock_cel/cel_value.h

@@ -0,0 +1,83 @@
+// Copyright 2020 gRPC authors.
+//
+// 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
+//
+//     http://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.
+
+#ifndef GRPC_CORE_LIB_SECURITY_AUTHORIZATION_MOCK_CEL_CEL_VALUE_H
+#define GRPC_CORE_LIB_SECURITY_AUTHORIZATION_MOCK_CEL_CEL_VALUE_H
+
+// CelValue is a holder, capable of storing all kinds of data
+// supported by CEL.
+// CelValue defines explicitly typed/named getters/setters.
+// When storing pointers to objects, CelValue does not accept ownership
+// to them and does not control their lifecycle. Instead objects are expected
+// to be either external to expression evaluation, and controlled beyond the
+// scope or to be allocated and associated with some allocation/ownership
+// controller (Arena).
+// Usage examples:
+// (a) For primitive types:
+//    CelValue value = CelValue::CreateInt64(1);
+// (b) For string:
+//    std::string* msg("test");
+//    CelValue value = CelValue::CreateString(msg);
+
+#include <grpc/support/port_platform.h>
+
+#include "absl/strings/string_view.h"
+
+namespace google {
+namespace api {
+namespace expr {
+namespace runtime {
+
+// Break cyclic depdendencies for container types.
+class CelMap;
+
+// This is a temporary stub implementation of CEL APIs.
+// Once gRPC imports the CEL library, this class will be removed.
+class CelValue {
+ public:
+  // Default constructor.
+  // Creates CelValue with null data type.
+  CelValue() : CelValue(nullptr) {}
+
+  // We will use factory methods instead of public constructors
+  // The reason for this is the high risk of implicit type conversions
+  // between bool/int/pointer types.
+  // We rely on copy elision to avoid extra copying.
+  static CelValue CreateNull() { return CelValue(nullptr); }
+
+  static CelValue CreateInt64(int64_t value) { return CreateNull(); }
+
+  static CelValue CreateUint64(uint64_t value) { return CreateNull(); }
+
+  static CelValue CreateStringView(absl::string_view value) {
+    return CreateNull();
+  }
+
+  static CelValue CreateString(const std::string* str) { return CreateNull(); }
+
+  static CelValue CreateMap(const CelMap* value) { return CreateNull(); }
+
+ private:
+  // Constructs CelValue wrapping value supplied as argument.
+  // Value type T should be supported by specification of ValueHolder.
+  template <class T>
+  explicit CelValue(T value) {}
+};
+
+}  // namespace runtime
+}  // namespace expr
+}  // namespace api
+}  // namespace google
+
+#endif  // GRPC_CORE_LIB_SECURITY_AUTHORIZATION_MOCK_CEL_CEL_VALUE_H