/* * Copyright (c) Facebook, Inc. and its affiliates. * * 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. */ #pragma once #include <string> #include <vector> #include <folly/Expected.h> #include <folly/Range.h> namespace folly { /* * json_pointer * * As described in RFC 6901 "JSON Pointer". * * Implements parsing. Traversal using the pointer over data structures must be * implemented separately. */ class json_pointer { public: enum class parse_error { invalid_first_character, invalid_escape_sequence, }; class parse_exception : public std::runtime_error { using std::runtime_error::runtime_error; }; json_pointer() = default; ~json_pointer() = default; /* * Parse string into vector of unescaped tokens. * Non-throwing and throwing versions. */ static Expected<json_pointer, parse_error> try_parse(StringPiece const str); static json_pointer parse(StringPiece const str); /* * Return true if this pointer is proper to prefix to another pointer */ bool is_prefix_of(json_pointer const& other) const noexcept; /* * Get access to the parsed tokens for applications that want to traverse * the pointer. */ std::vector<std::string> const& tokens() const; friend bool operator==(json_pointer const& lhs, json_pointer const& rhs) { return lhs.tokens_ == rhs.tokens_; } friend bool operator!=(json_pointer const& lhs, json_pointer const& rhs) { return lhs.tokens_ != rhs.tokens_; } private: explicit json_pointer(std::vector<std::string>) noexcept; /* * Unescape the specified escape sequences, returns false if incorrect */ static bool unescape(std::string&); std::vector<std::string> tokens_; }; } // namespace folly