cel-cpp/checker/type_checker_builder.h at 8d527656cef2908a96d4feeafa7a3730d8531655 · cel-expr/cel-cpp · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
// Copyright 2024 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.

#ifndef THIRD_PARTY_CEL_CPP_CHECKER_TYPE_CHECKER_BUILDER_H_
#define THIRD_PARTY_CEL_CPP_CHECKER_TYPE_CHECKER_BUILDER_H_

#include <memory>
#include <string>
#include <utility>
#include <vector>

#include "absl/base/nullability.h"
#include "absl/container/flat_hash_set.h"
#include "absl/functional/any_invocable.h"
#include "absl/status/status.h"
#include "absl/status/statusor.h"
#include "absl/strings/string_view.h"
#include "checker/checker_options.h"
#include "checker/internal/type_check_env.h"
#include "checker/type_checker.h"
#include "common/decl.h"
#include "common/type.h"
#include "common/type_introspector.h"
#include "google/protobuf/descriptor.h"

namespace cel {

class TypeCheckerBuilder;

// Functional implementation to apply the library features to a
// TypeCheckerBuilder.
using TypeCheckerBuilderConfigurer =
    absl::AnyInvocable<absl::Status(TypeCheckerBuilder&) const>;

struct CheckerLibrary {
  // Optional identifier to avoid collisions re-adding the same declarations.
  // If id is empty, it is not considered.
  std::string id;
  TypeCheckerBuilderConfigurer configure;
};

// Builder for TypeChecker instances.
class TypeCheckerBuilder {
 public:
  TypeCheckerBuilder(const TypeCheckerBuilder&) = delete;
  TypeCheckerBuilder(TypeCheckerBuilder&&) = default;
  TypeCheckerBuilder& operator=(const TypeCheckerBuilder&) = delete;
  TypeCheckerBuilder& operator=(TypeCheckerBuilder&&) = default;

  absl::StatusOr<std::unique_ptr<TypeChecker>> Build() &&;

  absl::Status AddLibrary(CheckerLibrary library);

  absl::Status AddVariable(const VariableDecl& decl);
  absl::Status AddFunction(const FunctionDecl& decl);

  void SetExpectedType(const Type& type);

  // Adds function declaration overloads to the TypeChecker being built.
  //
  // Attempts to merge with any existing overloads for a function decl with the
  // same name. If the overloads are not compatible, an error is returned and
  // no change is made.
  absl::Status MergeFunction(const FunctionDecl& decl);

  void AddTypeProvider(std::unique_ptr<TypeIntrospector> provider);

  void set_container(absl::string_view container);

  const CheckerOptions& options() const { return options_; }

 private:
  friend absl::StatusOr<std::unique_ptr<TypeCheckerBuilder>>
  CreateTypeCheckerBuilder(
      absl::Nonnull<std::shared_ptr<const google::protobuf::DescriptorPool>>
          descriptor_pool,
      const CheckerOptions& options);

  TypeCheckerBuilder(
      absl::Nonnull<std::shared_ptr<const google::protobuf::DescriptorPool>>
          descriptor_pool,
      const CheckerOptions& options)
      : options_(options), env_(std::move(descriptor_pool)) {}

  CheckerOptions options_;
  std::vector<CheckerLibrary> libraries_;
  absl::flat_hash_set<std::string> library_ids_;

  checker_internal::TypeCheckEnv env_;
};

}  // namespace cel

#endif  // THIRD_PARTY_CEL_CPP_CHECKER_TYPE_CHECKER_BUILDER_H_