typesense/include/synonym_index.h
2022-03-23 18:53:48 +05:30

139 lines
4.4 KiB
C++

#pragma once
#include <set>
#include "sparsepp.h"
#include "json.hpp"
#include "string_utils.h"
#include "option.h"
#include "tokenizer.h"
#include "store.h"
struct synonym_t {
std::string id;
std::vector<std::string> root;
std::vector<std::vector<std::string>> synonyms;
synonym_t() = default;
synonym_t(const std::string& id, const std::vector<std::string>& root,
const std::vector<std::vector<std::string>>& synonyms):
id(id), root(root), synonyms(synonyms) {
}
explicit synonym_t(const nlohmann::json& synonym) {
id = synonym["id"].get<std::string>();
if(synonym.count("root") != 0) {
root = synonym["root"].get<std::vector<std::string>>();
}
synonyms = synonym["synonyms"].get<std::vector<std::vector<std::string>>>();
}
nlohmann::json to_json() const {
nlohmann::json obj;
obj["id"] = id;
obj["root"] = root;
obj["synonyms"] = synonyms;
return obj;
}
nlohmann::json to_view_json() const {
nlohmann::json obj;
obj["id"] = id;
obj["root"] = StringUtils::join(root, " ");
obj["synonyms"] = nlohmann::json::array();
for(const auto& synonym: synonyms) {
obj["synonyms"].push_back(StringUtils::join(synonym, " "));
}
return obj;
}
static Option<bool> parse(const nlohmann::json& synonym_json, synonym_t& syn) {
if(synonym_json.count("id") == 0) {
return Option<bool>(400, "Missing `id` field.");
}
if(synonym_json.count("synonyms") == 0) {
return Option<bool>(400, "Could not find an array of `synonyms`");
}
if(synonym_json.count("root") != 0 && !synonym_json["root"].is_string()) {
return Option<bool>(400, "Key `root` should be a string.");
}
if (!synonym_json["synonyms"].is_array() || synonym_json["synonyms"].empty()) {
return Option<bool>(400, "Could not find an array of `synonyms`");
}
for(const auto& synonym: synonym_json["synonyms"]) {
if(!synonym.is_string() || synonym == "") {
return Option<bool>(400, "Could not find a valid string array of `synonyms`");
}
std::vector<std::string> tokens;
Tokenizer(synonym, true).tokenize(tokens);
syn.synonyms.push_back(tokens);
}
if(synonym_json.count("root") != 0) {
std::vector<std::string> tokens;
Tokenizer(synonym_json["root"], true).tokenize(tokens);
syn.root = tokens;
}
syn.id = synonym_json["id"];
return Option<bool>(true);
}
static uint64_t get_hash(const std::vector<std::string>& tokens) {
uint64_t hash = 1;
for(size_t i=0; i < tokens.size(); i++) {
auto& token = tokens[i];
uint64_t token_hash = StringUtils::hash_wy(token.c_str(), token.size());
if(i == 0) {
hash = token_hash;
} else {
hash = StringUtils::hash_combine(hash, token_hash);
}
}
return hash;
}
};
class SynonymIndex {
private:
mutable std::shared_mutex mutex;
Store* store;
spp::sparse_hash_map<std::string, synonym_t> synonym_definitions;
spp::sparse_hash_map<uint64_t, std::vector<std::string>> synonym_index;
void synonym_reduction_internal(const std::vector<std::string>& tokens,
size_t start_window_size,
size_t start_index_pos,
std::set<uint64_t>& processed_syn_hashes,
std::vector<std::vector<std::string>>& results) const;
public:
static constexpr const char* COLLECTION_SYNONYM_PREFIX = "$CY";
SynonymIndex(Store* store): store(store) { }
static std::string get_synonym_key(const std::string & collection_name, const std::string & synonym_id);
void synonym_reduction(const std::vector<std::string>& tokens,
std::vector<std::vector<std::string>>& results) const;
spp::sparse_hash_map<std::string, synonym_t> get_synonyms();
bool get_synonym(const std::string& id, synonym_t& synonym);
Option<bool> add_synonym(const std::string & collection_name, const synonym_t& synonym);
Option<bool> remove_synonym(const std::string & collection_name, const std::string & id);
};