Class Metadata

The Metadata instance tracks the state of an object and checks if the object state was changed since last load/update. The metadata keeps therefore the state of:

in which state the object currently is
which db managed the instance
the metadata of the object (id, version, bucket)
which is the owning object (root object) of an embedded object

Metadata#get(object) can be used on any managed object to retrieve the metadata of the root object

Hierarchy

Lockable
- Metadata

Implements

ManagedState

Index

Constructors

constructor

new Metadata(type: EntityType<any>): Metadata
Parameters
- type: EntityType<any>
Returns Metadata
Overrides Lockable.constructor
- Defined in lib/intersection/Metadata.ts:188

Properties

acl

acl: Acl

decodedKey

decodedKey: null | string = null

enabled

enabled: boolean

entityManager

entityManager: null | EntityManager = null

id

id: null | string = null

state

state: MetadataState

type

type: EntityType<any>

version

version: null | number

Accessors

bucket

get bucket(): string
Returns string
- Defined in lib/intersection/Metadata.ts:118

db

get db(): EntityManager
Returns EntityManager
Implementation of ManagedState.db
- Defined in lib/intersection/Metadata.ts:93
set db(db: EntityManager): void
Parameters
- db: EntityManager
Returns void
Implementation of ManagedState.db
- Defined in lib/intersection/Metadata.ts:106

isAttached

get isAttached(): boolean
Indicates if this object already belongs to an db true if this object belongs already to an db otherwise false

Returns boolean
- Defined in lib/intersection/Metadata.ts:154

isAvailable

get isAvailable(): boolean
Indicates if this object is represents a db object, but was not loaded up to now

Returns boolean
- Defined in lib/intersection/Metadata.ts:163

isDirty

get isDirty(): boolean
Indicates that this object was modified and the object was not written back to the db

Returns boolean
- Defined in lib/intersection/Metadata.ts:181

isPersistent

get isPersistent(): boolean
Indicates if this object represents the state of the db and was not modified in any manner

Returns boolean
- Defined in lib/intersection/Metadata.ts:172

isReady

get isReady(): boolean
Indicates if there is currently no exclusive operation executed true If no exclusive lock is hold

Returns boolean
Inherited from Lockable.isReady
- Defined in lib/util/Lockable.ts:29

key

get key(): null | string
Returns null | string
- Defined in lib/intersection/Metadata.ts:126

Methods

enable

enable(newStateTrackingState: boolean): void
Enable/Disable state change tracking of this object

Returns
Parameters
- newStateTrackingState: boolean
  
  The new change tracking state
Returns void
- Defined in lib/intersection/Metadata.ts:204

ready

ready(doneCallback?: ((this: Metadata) => any), failCallback?: ((error: Error) => any)): Promise<Metadata>
Waits on the previously requested operation and calls the doneCallback if the operation is fulfilled

Returns
A promise which completes successfully, when the previously requested operation completes
Parameters
- Optional doneCallback: ((this: Metadata) => any)
  
  The callback which will be invoked when the previously operations on this object is completed.
  - - (this: Metadata): any
    - Parameters
      
      this: Metadata
      
      Returns any
- Optional failCallback: ((error: Error) => any)
  
  When the lock can't be released caused by a none recoverable error
  - - (error: Error): any
    - Parameters
      
      error: Error
      
      Returns any
Returns Promise<Metadata>
Inherited from Lockable.ready
- Defined in lib/util/Lockable.ts:42

setDirty

setDirty(): void
Indicates the the object is modified by the user

Returns

Returns void
Implementation of ManagedState.setDirty
- Defined in lib/intersection/Metadata.ts:241

setPersistent

setPersistent(): void
Indicates that the associated object is not stale

An object is stale if it correlates the database state and is not modified by the user.

Returns

Returns void
- Defined in lib/intersection/Metadata.ts:233

setRemoved

setRemoved(): void
Indicates the the object is removed

Returns

Returns void
- Defined in lib/intersection/Metadata.ts:249

setUnavailable

setUnavailable(): void
Indicates that the associated object isn't available

Returns

Returns void
- Defined in lib/intersection/Metadata.ts:222

throwUnloadedPropertyAccess

throwUnloadedPropertyAccess(property: string): void
Throws the corresponding error if a property is accessed before the owning object is loaded

Throws
an exception if the object properties aren't available and the object is enabled
Parameters
- property: string
Returns void
- Defined in lib/intersection/Metadata.ts:212

`Protected` withLock

withLock<T>(callback: (() => Promise<T>), critical??: boolean): Promise<T>
Protected
Try to aquire an exclusive lock and executes the given callback.

Returns
A promise

Throws
If the lock can't be aquired
Type Parameters
- T
Parameters
- callback: (() => Promise<T>)
  
  The exclusive operation to execute
  - - (): Promise<T>
    - Returns Promise<T>
- Optional critical: boolean = false
  
  Indicates if the operation is critical. If the operation is critical and the operation fails, then the lock will not be released
Returns Promise<T>
Inherited from Lockable.withLock
- Defined in lib/util/Lockable.ts:55

`Static` create

create<T>(type: ManagedType<T>, db?: EntityManager): ManagedState
Creates temporary metadata instance for the given embeddable type

Returns
The created metadata for the object
Type Parameters
- T extends Managed<T>
Parameters
- type: ManagedType<T>
  
  The type of the object
- Optional db: EntityManager
  
  a EntityManager which will be attached to the state
Returns ManagedState
- Defined in lib/intersection/Metadata.ts:59
create<T>(type: EntityType<T>, db?: EntityManager): Metadata | ManagedState
Creates a metadata instance for the given entity type

Returns
The created metadata for the object
Type Parameters
- T extends Entity<T>
Parameters
- type: EntityType<T>
  
  The type of the object
- Optional db: EntityManager
  
  a optional EntityManager which will be attached to the state
Returns Metadata | ManagedState
- Defined in lib/intersection/Metadata.ts:68

`Static` get

get(managed: Entity): Metadata
Returns the metadata of the managed object

Returns
Parameters
- managed: Entity
Returns Metadata
- Defined in lib/intersection/Metadata.ts:85

Class Metadata

Hierarchy

Implements

Index

Constructors

Properties

Accessors

Methods

Constructors

constructor

Parameters

type: EntityType<any>

Returns Metadata

Properties

acl

decodedKey

enabled

entityManager

id

state

type

version

Accessors

bucket

Returns string

db

Returns EntityManager

Parameters

db: EntityManager

Returns void

isAttached

Returns boolean

isAvailable

Returns boolean

isDirty

Returns boolean

isPersistent

Returns boolean

isReady

Returns boolean

key

Returns null | string

Methods

enable

Returns

Parameters

newStateTrackingState: boolean

Returns void

ready

Returns

Parameters

Optional doneCallback: ((this: Metadata) => any)

Parameters

this: Metadata

Returns any

Optional failCallback: ((error: Error) => any)

Parameters

error: Error

Returns any

Returns Promise<Metadata>

setDirty

Returns

Returns void

setPersistent

Returns

Returns void

setRemoved

Returns

Returns void

setUnavailable

Returns

Returns void

throwUnloadedPropertyAccess

Throws

Parameters

property: string

Returns void

Protected withLock

Returns

Throws

`Optional` doneCallback: ((this: Metadata) => any)

`Optional` failCallback: ((error: Error) => any)

`Protected` withLock

`Optional` critical: boolean = false

`Static` create

`Optional` db: EntityManager

`Optional` db: EntityManager

`Static` get