realm-js/object_accessor.hpp

197 lines
8.0 KiB
C++

////////////////////////////////////////////////////////////////////////////
//
// Copyright 2015 Realm Inc.
//
// 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 REALM_OBJECT_ACCESSOR_HPP
#define REALM_OBJECT_ACCESSOR_HPP
#include <string>
#include "shared_realm.hpp"
namespace realm {
template<typename ValueType, typename ContextType>
class NativeAccessor {
public:
//
// Value converters - template specializations must be implemented for each platform
//
static ValueType dict_value_for_key(ContextType ctx, ValueType dict, const std::string &prop_name);
static bool to_bool(ContextType ctx, ValueType &val);
static long long to_long(ContextType ctx, ValueType &val);
static float to_float(ContextType ctx, ValueType &val);
static double to_double(ContextType ctx, ValueType &val);
static std::string to_string(ContextType ctx, ValueType &val);
static DateTime to_datetime(ContextType ctx, ValueType &val);
static bool is_null(ContextType ctx, ValueType &val);
// convert value to persisted object
// for existing objects return the existing row index
// for new/updated objects return the row index
static size_t to_object_index(ContextType ctx, SharedRealm &realm, ValueType &val, Property &prop, bool try_update);
// array value acessors
static size_t array_size(ContextType ctx, ValueType &val);
static ValueType array_value_at_index(ContextType ctx, ValueType &val, size_t index);
//
// Deprecated
//
static Mixed to_mixed(ContextType ctx, ValueType &val) { throw std::runtime_error("'Any' type is unsupported"); }
};
class Object {
public:
Object(SharedRealm &r, ObjectSchema &s, Row o) : realm(r), object_schema(s), row(o) {}
// FIXME - all should be const
SharedRealm realm;
ObjectSchema &object_schema;
Row row;
// property setter
template<typename ValueType, typename ContextType>
inline void set_property_value(ContextType ctx, std::string prop_name, ValueType value, bool try_update);
// create an Object from a native representation
template<typename ValueType, typename ContextType>
static inline Object create(ContextType ctx, SharedRealm realm, ObjectSchema &object_schema, ValueType value, bool try_update);
private:
template<typename ValueType, typename ContextType>
inline void set_property_value_impl(ContextType ctx, Property &property, ValueType value, bool try_update);
};
//
// template method implementations
//
template <typename ValueType, typename ContextType>
inline void Object::set_property_value(ContextType ctx, std::string prop_name, ValueType value, bool try_update)
{
Property *prop = object_schema.property_for_name(prop_name);
if (!prop) {
throw std::runtime_error("Setting invalid property '" + prop_name + "' on object '" + object_schema.name + "'.");
}
set_property_value_impl(ctx, *prop, value, try_update);
};
template <typename ValueType, typename ContextType>
inline void Object::set_property_value_impl(ContextType ctx, Property &property, ValueType value, bool try_update)
{
using Accessor = NativeAccessor<ValueType, ContextType>;
size_t column = property.table_column;
switch (property.type) {
case PropertyTypeBool:
row.set_bool(column, Accessor::to_bool(ctx, value));
break;
case PropertyTypeInt:
row.set_int(column, Accessor::to_long(ctx, value));
break;
case PropertyTypeFloat:
row.set_float(column, Accessor::to_float(ctx, value));
break;
case PropertyTypeDouble:
row.set_double(column, Accessor::to_double(ctx, value));
break;
case PropertyTypeString:
row.set_string(column, Accessor::to_string(ctx, value));
break;
case PropertyTypeData:
row.set_binary(column, BinaryData(Accessor::to_string(ctx, value)));
break;
case PropertyTypeAny:
row.set_mixed(column, Accessor::to_mixed(ctx, value));
break;
case PropertyTypeDate:
row.set_datetime(column, Accessor::to_datetime(ctx, value));
break;
case PropertyTypeObject: {
if (Accessor::is_null(ctx, value)) {
row.nullify_link(column);
}
else {
row.set_link(column, Accessor::to_object_index(ctx, realm, value, property, try_update));
}
break;
}
case PropertyTypeArray: {
realm::LinkViewRef link_view = row.get_linklist(column);
link_view->clear();
size_t count = Accessor::array_size(ctx, value);
for (size_t i = 0; i < count; i++) {
ValueType element = Accessor::array_value_at_index(ctx, value, i);
link_view->add(Accessor::to_object_index(ctx, realm, element, property, try_update));
}
break;
}
}
}
template<typename ValueType, typename ContextType>
inline Object Object::create(ContextType ctx, SharedRealm realm, ObjectSchema &object_schema, ValueType value, bool try_update)
{
using Accessor = NativeAccessor<ValueType, ContextType>;
if (!realm->is_in_transaction()) {
throw std::runtime_error("Can only create objects within a transaction.");
}
// get or create our accessor
bool created;
// try to get existing row if updating
size_t row_index = realm::not_found;
realm::TableRef table = ObjectStore::table_for_object_type(realm->read_group(), object_schema.name);
Property *primary_prop = object_schema.primary_key_property();
if (try_update && primary_prop) {
// search for existing object based on primary key type
ValueType primary_value = Accessor::dict_value_for_key(ctx, value, object_schema.primary_key);
if (primary_prop->type == PropertyTypeString) {
row_index = table->find_first_string(primary_prop->table_column, Accessor::to_string(ctx, primary_value));
}
else {
row_index = table->find_first_int(primary_prop->table_column, Accessor::to_long(ctx, primary_value));
}
}
// if no existing, create row
created = false;
if (row_index == realm::not_found) {
row_index = table->add_empty_row();
created = true;
}
// populate
Object object(realm, object_schema, table->get(row_index));
for (Property &prop : object_schema.properties) {
ValueType prop_value = Accessor::dict_value_for_key(ctx, value, prop.name);
if (prop_value) {
if (created || !prop.is_primary) {
object.set_property_value_impl(ctx, prop, prop_value, try_update);
}
}
else if (created) {
throw std::runtime_error("Missing property value for property " + prop.name);
}
}
return object;
}
}
#endif /* defined(REALM_OBJECT_ACCESSOR_HPP) */