typeorm
Version:
Data-Mapper ORM for TypeScript and ES2021+. Supports MySQL/MariaDB, PostgreSQL, MS SQL Server, Oracle, SAP HANA, SQLite, MongoDB databases.
113 lines (111 loc) • 4.82 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.PlainObjectToDatabaseEntityTransformer = void 0;
/**
*/
class LoadMapItem {
constructor(plainEntity, metadata, parentLoadMapItem, relation) {
this.plainEntity = plainEntity;
this.metadata = metadata;
this.parentLoadMapItem = parentLoadMapItem;
this.relation = relation;
}
get target() {
return this.metadata.target;
}
get id() {
return this.metadata.getEntityIdMixedMap(this.plainEntity);
}
}
class LoadMap {
constructor() {
this.loadMapItems = [];
}
get mainLoadMapItem() {
return this.loadMapItems.find((item) => !item.relation && !item.parentLoadMapItem);
}
addLoadMap(newLoadMap) {
const item = this.loadMapItems.find((item) => item.target === newLoadMap.target && item.id === newLoadMap.id);
if (!item)
this.loadMapItems.push(newLoadMap);
}
fillEntities(target, entities) {
entities.forEach((entity) => {
const item = this.loadMapItems.find((loadMapItem) => {
return (loadMapItem.target === target &&
loadMapItem.metadata.compareEntities(entity, loadMapItem.plainEntity));
});
if (item)
item.entity = entity;
});
}
groupByTargetIds() {
const groups = [];
this.loadMapItems.forEach((loadMapItem) => {
let group = groups.find((group) => group.target === loadMapItem.target);
if (!group) {
group = { target: loadMapItem.target, ids: [] };
groups.push(group);
}
group.ids.push(loadMapItem.id);
});
return groups;
}
}
/**
* Transforms plain old javascript object
* Entity is constructed based on its entity metadata.
*/
class PlainObjectToDatabaseEntityTransformer {
constructor(manager) {
this.manager = manager;
}
// -------------------------------------------------------------------------
// Public Methods
// -------------------------------------------------------------------------
async transform(plainObject, metadata) {
// if plain object does not have id then nothing to load really
if (!metadata.hasAllPrimaryKeys(plainObject))
return Promise.reject("Given object does not have a primary column, cannot transform it to database entity.");
// create a special load map that will hold all metadata that will be used to operate with entities easily
const loadMap = new LoadMap();
const fillLoadMap = (entity, entityMetadata, parentLoadMapItem, relation) => {
const item = new LoadMapItem(entity, entityMetadata, parentLoadMapItem, relation);
loadMap.addLoadMap(item);
entityMetadata
.extractRelationValuesFromEntity(entity, metadata.relations)
.filter((value) => value !== null && value !== undefined)
.forEach(([relation, value, inverseEntityMetadata]) => fillLoadMap(value, inverseEntityMetadata, item, relation));
};
fillLoadMap(plainObject, metadata);
// load all entities and store them in the load map
await Promise.all(loadMap.groupByTargetIds().map((targetWithIds) => {
// todo: fix type hinting
return this.manager
.findByIds(targetWithIds.target, targetWithIds.ids)
.then((entities) => loadMap.fillEntities(targetWithIds.target, entities));
}));
// go through each item in the load map and set their entity relationship using metadata stored in load map
loadMap.loadMapItems.forEach((loadMapItem) => {
if (!loadMapItem.relation ||
!loadMapItem.entity ||
!loadMapItem.parentLoadMapItem ||
!loadMapItem.parentLoadMapItem.entity)
return;
if (loadMapItem.relation.isManyToMany ||
loadMapItem.relation.isOneToMany) {
if (!loadMapItem.parentLoadMapItem.entity[loadMapItem.relation.propertyName])
loadMapItem.parentLoadMapItem.entity[loadMapItem.relation.propertyName] = [];
loadMapItem.parentLoadMapItem.entity[loadMapItem.relation.propertyName].push(loadMapItem.entity);
}
else {
loadMapItem.parentLoadMapItem.entity[loadMapItem.relation.propertyName] = loadMapItem.entity;
}
});
return loadMap.mainLoadMapItem
? loadMap.mainLoadMapItem.entity
: undefined;
}
}
exports.PlainObjectToDatabaseEntityTransformer = PlainObjectToDatabaseEntityTransformer;
//# sourceMappingURL=PlainObjectToDatabaseEntityTransformer.js.map