LiteData

A light weight wrapper around core data in swift. The goal of this project is to provide different layer of abstraction on top of core data, so that depends on the need we can use a higher level of abstraction for convenient or simply drop down to the next layer to have more interaction and flexibility

Managed Object Layer (TO DO)

Let's be plain. we don't want to deal with MOC interaction, we don't want to call a custom class to perform core data operation. Sometimes we just want deal with the managed objects themselves. This provide the highest abstraction. Thus it lacks of features such as temporary (unsaved) objects and completion block. However, it gives the best simplicity and very useful for batch operations.

Write Operation

• To insert a Book object

Book.add { creatingBook in
  creatingBook.title = "A mid summer night dream"
  creatingBook.author = "Shakespear"
}

• Then edit it

shakespearBook.edit { editingBook in
  editingBook.publisher = "The Great Publisher"  
}

• And if we want to delete it

shakespearBook.remove() 

• Batch operation

LiteData.batchOperation {
  let author = Author.add { creatingAuthor in
    creatingAuthor.name = "Shakespear"
  }

  Book.add { creatingBook in
    creatingBook.title = "A mid summer night dream"
    creatingBook.publisher = "The Great Publisher"
    creatingBook.author = author
  }
}

Read Operation

TODO:

LiteData layer (IN PROGRESS)

This provide the next level of abstraction. We can use this anywhere on main thread for read/write operation without having to worry about the MOC interaction behind the scene. It provides dot notation to chain operations

Write Operation

• To insert a Book object

LiteData.entity(Book.self).add({ creatingBook in
  creatingBook.title = "A mid summer night dream"
  creatingBook.author = "Shakespear"
}).persist()

• Then edit it

LiteData.entity(shakespearBook).edit({ editingBook in
  editingBook.publisher = "The Great Publisher"
}).persist()

• And if we want to delete it

LiteData.entity(shakespearBook).remove().persist {
  // completion closure
}

• If we want to just create the object and not persist it immediately, we can store it in a DataEntity variable

let adventureBook = LiteData.entity(Book.self).add { creatingBook in
  creatingBook.title = "The adventure of Tom Sawyer"
  creatingBook.author = "Mark Twain"
}

// later on call
adventureBook.persist {
  // completion closure
}

Read Opearation

• Get one book

let tomSawyerBook = LiteData.readEntity(Book.self).fetchOne(predicate)

• Get some book

let literatureBooks = LiteData.readEntity(Book.self).fetch(predicate)

• Batching

let adventureBooks = LiteData.readEntity(Book.self).batch(10).fetch(predicate)

• Sorting

let adventureBooks = LiteData.readEntity(Book.self).sort(sortDescriptor).fetch(predicate)

• Let's try something complicated

let readEntity = LiteData.readEntity(Book.self)
readEntity.batch(10)
readEntity.sort(sortDescriptor)

let adventureBooks = readEntity.fetch()

\\ Not too bad? :)

Observing Changes

TODO:

Notes

• All write operation happens asynchronously and not blocking the main thread.
• A DataEntity object is returned at the end of any operation during the chain
• You can call persist with completion closure or simply call persist(). The completion closure is returned on the background thread. You have the option to dispatch_async back to main thread to perform any UI updates.
• These are just specs at the moment. This is a WORK IN PROGRESS and TENTATIVE TO CHANGE depends on the technical feasibility

ManagedObject Context Layer

This provide the most light weight abstraction around core data write operation. It has interface identical to performBlock and performBlockAndWait api on the NSManagedObjectContext. This allow you to managed the threading and MOC hierachy yourself yet ensure the integrity when modifying object across different threads.

Write Operation

• To insert a Book object

let context = LiteData.sharedInstance.writeContext()
context.createEntity(Book.self) { creatingBook in
  creatingEntity.name = "Gulliver's travel"
  creatingEntity.author = "Mark Twain"
}

• If we just want to edit and not persist

context.editEntity(gulliverBook, persisted: false) { editingBook in 
  editingBook.publisher = "Travel Publisher"
}

• And if we want to delete it

context.deleteEntity(gulliverBook)