query/include/matador/object/schema.hpp

371 lines
15 KiB
C++

#ifndef SCHEMA_HPP
#define SCHEMA_HPP
#include "matador/logger/log_manager.hpp"
#include "matador/object/many_to_many_relation.hpp"
#include "matador/object/primary_key_resolver.hpp"
#include "matador/object/error_code.hpp"
#include "matador/object/schema_node.hpp"
#include "matador/object/schema_node_iterator.hpp"
#include "matador/utils/result.hpp"
#include "matador/utils/error.hpp"
#include "matador/logger/logger.hpp"
#include <memory>
#include <stack>
#include <string>
#include <unordered_set>
namespace matador::object {
utils::error make_error(error_code ec, const std::string& msg);
class schema;
/*
* 1. has_many (MM)
* no belongs to
* relation table is needed
* - element type is a foreign table (FT),
* then relation table must look like follows:
* relation_table<MM, FT>
* where MM and FT must be defined as belongs to
* - element type if a builtin type BT (i.e. string, int, etc.),
* then the relation table must look like follows:
* relation_table<MM, BT>
* where MM as belongs to and BT as given type
*
* 2. has_many_to_many (MM1, MM2)
* relation_table is needed
* relation_table<MM1, MM2>
* where MM1 and MM2 must be defined as belongs to
*
* 3. hans_many (MM) <-> belongs_to (BT)
* belongs_to has foreign key to the has_many side
* no relation table needed
*
* 4. has_one to belongs_to
* no relation table is needed
*
* 5. has_many (MM) <-> has_one (HO)
* invalid relation -> error
*
* 6. has_one
* no has_many or belongs_to
* invalid relation -> error
*/
template<typename Type>
class relation_completer final {
public:
using value_type = Type;
static void complete(const std::shared_ptr<schema_node> &node) {
relation_completer completer(node);
Type obj;
access::process(completer, obj);
}
template < class PrimaryKeyType >
static void on_primary_key(const char * /*id*/, PrimaryKeyType &/*pk*/, std::enable_if_t<std::is_integral_v<PrimaryKeyType> && !std::is_same_v<bool, PrimaryKeyType>>* = nullptr) {}
static void on_primary_key(const char * /*id*/, std::string &/*pk*/, size_t /*size*/) {}
static void on_revision(const char * /*id*/, uint64_t &/*rev*/) {}
template<typename AttributeType>
static void on_attribute(const char * /*id*/, AttributeType &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
template<typename AttributeType>
static void on_attribute(const char * /*id*/, std::optional<AttributeType> &/*val*/, const utils::field_attributes &/*attr*/ = utils::null_attributes) {}
template<class ForeignPointerType>
void on_belongs_to(const char *id, ForeignPointerType &obj, const utils::foreign_attributes &attr);
template<class ForeignPointerType>
void on_has_one(const char * /*id*/, ForeignPointerType &/*obj*/, const utils::foreign_attributes &/*attr*/);
template<class CollectionType>
void on_has_many(const char *id, CollectionType &, const char *join_column, const utils::foreign_attributes &attr, std::enable_if_t<is_object_ptr<typename CollectionType::value_type>::value>* = nullptr );
template<class CollectionType>
void on_has_many(const char *id, CollectionType &, const char *join_column, const utils::foreign_attributes &attr, std::enable_if_t<!is_object_ptr<typename CollectionType::value_type>::value>* = nullptr );
template<class CollectionType>
void on_has_many_to_many(const char *id, CollectionType &collection, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes &attr);
template<class ContainerType>
void on_has_many_to_many(const char *id, ContainerType &collection, const utils::foreign_attributes &attr);
private:
explicit relation_completer(const std::shared_ptr<schema_node>& node)
: node_(node)
, schema_(node->schema_)
, log_(logger::create_logger("relation_completer")) {}
private:
std::shared_ptr<schema_node> node_;
schema& schema_;
logger::logger log_;
};
class schema {
public:
typedef const_schema_node_iterator const_iterator; /**< Shortcut for the list const iterator. */
/**
* Creates an empty schema
*/
explicit schema( std::string name = "");
template <typename Type>
[[nodiscard]] utils::result<void, utils::error> attach(const std::string& name, const std::string &parent = "") {
// if (has_node(name)) {
// return utils::failure(make_error(error_code::NodeAlreadyExists, "Node '" + name + "' already exists"));
// }
auto node = acquire_node<Type>(name);
log_.info("attach node %s", name.c_str());
relation_completer<Type>::complete(node);
if (auto result = attach_node(node, parent); !result) {
return utils::failure(result.err());
}
return utils::ok<void>();
}
template <typename Type, typename SuperType>
[[nodiscard]] utils::result<void, utils::error> attach(const std::string name) {
const auto ti = std::type_index(typeid(SuperType));
auto result = find_node(ti);
if (!result) {
return utils::failure(make_error(error_code::NodeNotFound, "Parent node '" + std::string(ti.name()) + "' not found"));
}
return attach<Type>(name, (*result)->name());
}
/**
* Return the first schema node.
*
* @return The first schema node iterator.
*/
[[nodiscard]] const_iterator begin() const;
/**
* Return the last schema node.
*
* @return The last schema node iterator.
*/
[[nodiscard]] const_iterator end() const;
/**
* Returns true if the schema contains
* no schema nodes.
*
* @return True if the schema is empty
*/
[[nodiscard]] bool empty() const;
/**
* Returns the current number of the schema node.
*
* @return Number of schema nodes
*/
[[nodiscard]] size_t size() const;
/**
* Returns the name of the schema.
*
* @return The name of the schema
*/
[[nodiscard]] std::string name() const;
template <typename Type>
[[nodiscard]] utils::result<object_info_ref<Type>, utils::error> info() const {
auto result = find_node(std::type_index(typeid(Type)));
if (!result) {
return utils::failure(result.err());
}
return utils::ok(result.value()->info<Type>());
}
template <typename Type>
[[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info() const {
auto result = find_node(std::type_index(typeid(Type)));
if (!result) {
return utils::failure(result.err());
}
return utils::ok(basic_object_info_ref{result.value()->info()});
}
[[nodiscard]] utils::result<std::shared_ptr<attribute_definition>, utils::error> reference(const std::type_index &type_index) const;
private:
using node_ptr = std::shared_ptr<schema_node>;
using t_node_map = std::unordered_map<std::string, node_ptr>;
using t_type_index_node_map = std::unordered_map<std::type_index, node_ptr>;
[[nodiscard]] utils::result<std::shared_ptr<schema_node>, utils::error> attach_node(const std::shared_ptr<schema_node> &node,
const std::string &parent);
[[nodiscard]] utils::result<std::shared_ptr<schema_node>, utils::error> attach_node(const std::shared_ptr<schema_node> &node,
const std::type_index &type_index);
[[nodiscard]] utils::result<std::shared_ptr<schema_node>, utils::error> find_node(const std::string &name) const;
[[nodiscard]] utils::result<std::shared_ptr<schema_node>, utils::error> find_node(const std::type_index &type_index) const;
template <typename Type>
std::shared_ptr<schema_node> acquire_node(const std::string& name) {
if (const auto it = expected_node_map_.find(typeid(Type)); it != expected_node_map_.end()) {
const auto node = it->second;
expected_node_map_.erase(it);
node->update_name(name);
return node;
}
return schema_node::make_node<Type>(*this, name);
}
[[nodiscard]] bool has_node(const std::string &name) const;
[[nodiscard]] bool has_node(const std::type_index& index) const;
[[nodiscard]] bool has_node(const std::type_index& index, const std::string &name) const;
static void push_back_child(const node_ptr &parent, const node_ptr &child);
private:
template <typename Type>
friend class relation_completer;
std::string name_;
std::shared_ptr<schema_node> root_;
t_node_map nodes_by_name_;
t_type_index_node_map nodes_by_type_;
t_type_index_node_map expected_node_map_;
logger::logger log_;
};
template<typename Type>
template<class CollectionType>
void relation_completer<Type>::on_has_many( const char *id, CollectionType&,
const char *join_column,
const utils::foreign_attributes&,
std::enable_if_t<is_object_ptr<typename CollectionType::value_type>::value>* /*unused*/ ) {
using value_type = typename CollectionType::value_type::value_type;
// Check if the object_ptr type is already inserted in the schema (by id)
if (auto result = schema_.find_node(id); !result) {
const std::type_index ti = typeid(many_to_many_relation<value_type, Type>);
const auto endpoint = node_->info().find_relation_endpoint(ti);
if (endpoint == node_->info().endpoint_end()) {
log_.debug("node '%s' has has many foreign keys '%s' mapped by '%s'", node_->name().c_str(), id, join_column);
const auto node = schema_node::make_relation_node<many_to_many_relation<value_type, Type>>(schema_, id, [join_column] {
return std::make_unique<many_to_many_relation<value_type, Type>>(join_column, "id");
});
log_.debug("node '%s' many to many type: %s", node_->name().c_str(), typeid(many_to_many_relation<value_type, Type>).name());
result = schema_.attach_node(node, "");
if (!result) {
// Todo: throw internal error
return;
}
node_->info_->register_relation_endpoint(node->type_index(), relation_endpoint(id, relation_type::BELONGS_TO, node));
node->info_->register_relation_endpoint(node_->type_index(), relation_endpoint(id, relation_type::HAS_MANY, node_));
}
} else {
}
}
template<typename Type>
template<class CollectionType>
void relation_completer<Type>::on_has_many( const char *id, CollectionType&, const char *join_column, const utils::foreign_attributes&, std::enable_if_t<!is_object_ptr<typename CollectionType::value_type>::value>* /*unused*/ ) {
using value_type = typename CollectionType::value_type;
const auto node = schema_node::make_relation_node<many_to_many_relation<value_type, Type>>(schema_, id, [join_column] {
return new many_to_many_relation<value_type, Type>(join_column, "value");
});
const auto result = schema_.attach<many_to_relation<Type, value_type>>(id);
if (!result) {
// Todo: throw internal exception
}
}
template<typename Type>
template<class CollectionType>
void relation_completer<Type>::on_has_many_to_many( const char *id, CollectionType &/*collection*/, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes &attr) {
auto result = schema_.find_node(id);
if (result) {
} else {
//
using relation_type = many_to_many_relation<typename CollectionType::value_type, Type>;
auto creator = [join_column, inverse_join_column] {
return new many_to_many_relation<typename CollectionType::value_type, Type>(join_column, inverse_join_column);
};
// auto node = schema_node::make_relation_node<relation_type>(schema_, id);
// schema_.attach_node(node, typeid(relation_type));
}
}
template<typename Type>
template<class ContainerType>
void relation_completer<Type>::on_has_many_to_many( const char *id, ContainerType &collection, const utils::foreign_attributes &attr ) {
auto result = schema_.find_node(id);
if (!result) {
using relation_type = many_to_many_relation<typename ContainerType::value_type, Type>;
// auto creator = [attr] {
// return new relation_type(attr.join_column, attr.inverse_join_column);
// };
}
}
template<typename Type>
template<class ForeignPointerType>
void relation_completer<Type>::on_has_one(const char * id, ForeignPointerType &/*obj*/, const utils::foreign_attributes &/*attr*/) {
auto endpoint = std::make_shared<relation_endpoint>(std::string(id), relation_type::HAS_ONE, std::shared_ptr<schema_node>());
auto ti = std::type_index(typeid(typename ForeignPointerType::value_type));
if (const auto result = schema_.find_node(ti); !result.is_ok() && schema_.expected_node_map_.count(ti) == 0) {
schema_.expected_node_map_.insert({ti, schema_node::make_node<typename ForeignPointerType::value_type>(schema_, ti.name())});
} else {
const auto& foreign_node = result.value();
if (const auto rit = foreign_node->info().find_relation_endpoint(ti); rit != foreign_node->info().endpoint_end()) {
if (rit->second.is_has_many()) {
} else if (rit->second.is_has_one()) {
} else {
}
}
}
}
template<typename Type>
template<class ForeignPointerType>
void relation_completer<Type>::on_belongs_to(const char* id, ForeignPointerType& /*obj*/, const utils::foreign_attributes& /*attr*/) {
auto ti = std::type_index(typeid(typename ForeignPointerType::value_type));
if (auto result = schema_.find_node(ti); !result) {
log_.debug("node '%s' has foreign key '%s' belongs to '%s'", node_->name().c_str(), id, typeid(typename ForeignPointerType::value_type).name());
} else {
const auto foreign_node = result.value();
auto it = foreign_node->info().find_relation_endpoint(node_->type_index());
if (it != foreign_node->info().endpoint_end()) {
auto endpoint = it->second;
}
using TP = many_to_many_relation<typename ForeignPointerType::value_type, Type>;
log_.debug("node '%s', many to many type: %s", node_->name().c_str(), typeid(TP).name());
log_.debug("foreign node '%s', many to many type: %s", foreign_node->name().c_str(), ti.name());
if (foreign_node->type_index() == ti) {
log_.debug("node '%s' has foreign key '%s' belongs to '%s': already inserted", node_->name().c_str(), id, result.value()->name().c_str());
} else {
}
}
}
}
#endif //SCHEMA_HPP