typeorm
Version:
Data-Mapper ORM for TypeScript, ES7, ES6, ES5. Supports MySQL, PostgreSQL, MariaDB, SQLite, MS SQL Server, Oracle, MongoDB databases.
149 lines (147 loc) • 9.56 kB
JavaScript
import { Subject } from "../Subject";
import { OrmUtils } from "../../util/OrmUtils";
/**
* Builds operations needs to be executed for one-to-one non-owner relations of the given subjects.
*
* by example: post contains one-to-one non-owner relation with category in the property called "category", e.g.
* @OneToOne(type => Category, category => category.post) category: Category
* If user sets a category into the post and saves post we need to bind them.
* This operation requires updation of category table since its owner of the relation and contains a join column.
*
* note: this class shares lot of things with OneToManyUpdateBuilder, so when you change this class
* make sure to reflect changes there as well.
*/
var OneToOneInverseSideSubjectBuilder = /** @class */ (function () {
// ---------------------------------------------------------------------
// Constructor
// ---------------------------------------------------------------------
function OneToOneInverseSideSubjectBuilder(subjects) {
this.subjects = subjects;
}
// ---------------------------------------------------------------------
// Public Methods
// ---------------------------------------------------------------------
/**
* Builds all required operations.
*/
OneToOneInverseSideSubjectBuilder.prototype.build = function () {
var _this = this;
this.subjects.forEach(function (subject) {
subject.metadata.oneToOneRelations.forEach(function (relation) {
// we don't need owning relations, this operation is only for inverse side of one-to-one relations
// skip relations for which persistence is disabled
if (relation.isOwning || relation.persistenceEnabled === false)
return;
_this.buildForSubjectRelation(subject, relation);
});
});
};
// ---------------------------------------------------------------------
// Protected Methods
// ---------------------------------------------------------------------
/**
* Builds operations for a given subject and relation.
*
* by example: subject is "post" entity we are saving here and relation is "category" inside it here.
*/
OneToOneInverseSideSubjectBuilder.prototype.buildForSubjectRelation = function (subject, relation) {
// prepare objects (relation id map) for the database entity
// note: subject.databaseEntity contains relation with loaded relation id only (id map)
// by example: since subject is a post, we are expecting to get post's category saved in the database here,
// particularly its relation id, e.g. category id stored in the database
var relatedEntityDatabaseRelationId = undefined;
if (subject.databaseEntity) // related entity in the database can exist only if this entity (post) is saved
relatedEntityDatabaseRelationId = relation.getEntityValue(subject.databaseEntity);
// get related entities of persisted entity
// by example: get category from the passed to persist post entity
var relatedEntity = relation.getEntityValue(subject.entity); // by example: relatedEntity is a category here
if (relatedEntity === undefined) // if relation is undefined then nothing to update
return;
// if related entity is null then we need to check if there a bind in the database and unset it
// if there is no bind in the entity then we don't need to do anything
// by example: if post.category = null and category has this post in the database then we unset it
if (relatedEntity === null) {
// it makes sense to update database only there is a previously set value in the database
if (relatedEntityDatabaseRelationId) {
// todo: probably we can improve this in the future by finding entity with column those values,
// todo: maybe it was already in persistence process. This is possible due to unique requirements of join columns
// we create a new subject which operations will be executed in subject operation executor
var removedRelatedEntitySubject = new Subject({
metadata: relation.inverseEntityMetadata,
parentSubject: subject,
canBeUpdated: true,
identifier: relatedEntityDatabaseRelationId,
changeMaps: [{
relation: relation.inverseRelation,
value: null
}]
});
this.subjects.push(removedRelatedEntitySubject);
}
return;
} // else means entity is bind in the database
// extract only relation id from the related entities, since we only need it for comparision
// by example: extract from category only relation id (category id, or let's say category title, depend on join column options)
var relationIdMap = relation.inverseEntityMetadata.getEntityIdMap(relatedEntity); // by example: relationIdMap is category.id map here, e.g. { id: ... }
// try to find a subject of this related entity, maybe it was loaded or was marked for persistence
var relatedEntitySubject = this.subjects.find(function (operateSubject) {
return !!operateSubject.entity && operateSubject.entity === relatedEntity;
});
// if subject with entity was found take subject identifier as relation id map since it may contain extra properties resolved
if (relatedEntitySubject)
relationIdMap = relatedEntitySubject.identifier;
// if relationIdMap is undefined then it means user binds object which is not saved in the database yet
// by example: if post contains category which does not have id(s) yet (because its a new category)
// it means its always newly inserted and relation update operation always must be created for it
// it does not make sense to perform difference operation for it for both add and remove actions
if (!relationIdMap) {
// we decided to remove this error because it brings complications when saving object with non-saved entities
// if related entity does not have a subject then it means user tries to bind entity which wasn't saved
// in this persistence because he didn't pass this entity for save or he did not set cascades
// but without entity being inserted we cannot bind it in the relation operation, so we throw an exception here
// if (!relatedEntitySubject)
// throw new Error(`One-to-one inverse relation "${relation.entityMetadata.name}.${relation.propertyPath}" contains ` +
// `entity which does not exist in the database yet, thus cannot be bind in the database. ` +
// `Please setup cascade insertion or save entity before binding it.`);
if (!relatedEntitySubject)
return;
// okay, so related subject exist and its marked for insertion, then add a new change map
// by example: this will tell category to insert into its post relation our post we are working with
// relatedEntitySubject is newly inserted CategorySubject
// relation.inverseRelation is OneToOne owner relation inside Category
// subject is Post needs to be inserted into Category
relatedEntitySubject.changeMaps.push({
relation: relation.inverseRelation,
value: subject
});
}
// check if this binding really exist in the database
// by example: find our post if its already bind to category in the database and its not equal to what user tries to set
var areRelatedIdEqualWithDatabase = relatedEntityDatabaseRelationId && OrmUtils.compareIds(relationIdMap, relatedEntityDatabaseRelationId);
// if they aren't equal it means its a new relation and we need to "bind" them
// by example: this will tell category to insert into its post relation our post we are working with
// relatedEntitySubject is newly inserted CategorySubject
// relation.inverseRelation is ManyToOne relation inside Category
// subject is Post needs to be inserted into Category
if (!areRelatedIdEqualWithDatabase) {
// if there is no relatedEntitySubject then it means "category" wasn't persisted,
// but since we are going to update "category" table (since its an owning side of relation with join column)
// we create a new subject here:
if (!relatedEntitySubject) {
relatedEntitySubject = new Subject({
metadata: relation.inverseEntityMetadata,
canBeUpdated: true,
identifier: relationIdMap
});
this.subjects.push(relatedEntitySubject);
}
relatedEntitySubject.changeMaps.push({
relation: relation.inverseRelation,
value: subject
});
}
};
return OneToOneInverseSideSubjectBuilder;
}());
export { OneToOneInverseSideSubjectBuilder };
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