Inherits from NSObject
Conforms to RKObjectMappingDefinition
Declared in RKObjectMapping.h
RKObjectMapping.m

Overview

An object mapping defines the rules for transforming a key-value coding compliant object into another representation. The mapping is defined in terms of a source object class and a collection of rules defining how keyPaths should be transformed into target attributes and relationships.

There are two types of transformations possible:

  1. keyPath to attribute. Defines that the value found at the keyPath should be transformed and assigned to the property specified by the attribute. The transformation to be performed is determined by inspecting the type of the target property at runtime.
  2. keyPath to relationship. Defines that the value found at the keyPath should be transformed into another object instance and assigned to the property specified by the relationship. Relationships are processed using an object mapping as well.

Through the use of relationship mappings, an arbitrarily complex object graph can be mapped for you.

Instances of RKObjectMapping are used to configure RKObjectMappingOperation instances, which actually perform the mapping work. Both object loading and serialization are defined in terms of object mappings.

Tasks

Other Methods

  •   objectClass

    The target class this object mapping is defining rules for

         property
  •   mappings

    The aggregate collection of attribute and relationship mappings within this object mapping

         property
  •   attributeMappings

    The collection of attribute mappings within this object mapping

         property
  •   relationshipMappings

    The collection of relationship mappings within this object mapping

         property
  •   mappedKeyPaths

    The collection of mappable keyPaths that are defined within this object mapping. These keyPaths refer to keys within the source object being mapped (i.e. the parsed JSON payload).

         property
  •   rootKeyPath

    The root keyPath for this object. When the object mapping is being used for serialization and a root keyPath has been defined, the serialized object will be nested under this root keyPath before being encoded for transmission to a remote system.

         property
  •   setDefaultValueForMissingAttributes

    When YES, any attributes that have mappings defined but are not present within the source object will be set to nil, clearing any existing value.

         property
  •   setNilForMissingRelationships

    When YES, any relationships that have mappings defined but are not present within the source object will be set to nil, clearing any existing value.

         property
  •   performKeyValueValidation

    When YES, RestKit will invoke key-value validation at object mapping time.

         property
  •   forceCollectionMapping

    Forces the mapper to treat the mapped keyPath as a collection even if it does not return an array or a set of objects. This permits mapping where a dictionary identifies a collection of objects.

         property
  •   dateFormatters

    An array of NSDateFormatter objects to use when mapping string values into NSDate attributes on the target objectClass. Each date formatter will be invoked with the string value being mapped until one of the date formatters does not return nil.

         property
  •   preferredDateFormatter

    The NSDateFormatter instance for your application’s preferred date and time configuration. This date formatter will be used when generating string representations of NSDate attributes (i.e. during serialization to URL form encoded or JSON format).

         property
  • + mappingForClass:

    Returns an object mapping for the specified class that is ready for configuration
  • + serializationMapping

    Returns an object mapping useful for configuring a serialization mapping. The object class is configured as NSMutableDictionary
  • + mappingForClass:block:

    Returns an object mapping targeting the specified class. The RKObjectMapping instance will be yieled to the block so that you can perform on the fly configuration without having to obtain a reference variable for the mapping.
  • + serializationMappingWithBlock:

    Returns serialization mapping for encoding a local object to a dictionary for transport. The RKObjectMapping instance will be yieled to the block so that you can perform on the fly configuration without having to obtain a reference variable for the mapping.
  • – addAttributeMapping:

    Add a configured attribute mapping to this object mapping
  • – addRelationshipMapping:

    Add a configured attribute mapping to this object mapping
  • – mappingForKeyPath:

    Returns the attribute or relationship mapping for the given source keyPath.
  • – mappingForAttribute:

    Returns the attribute mapping targeting the specified attribute on the destination object
  • – mappingForRelationship:

    Returns the relationship mapping targeting the specified relationship on the destination object
  • – mapAttributes:

    Define an attribute mapping for one or more keyPaths where the source keyPath and destination attribute property have the same name.
  • – mapAttributesFromSet:

    Defines an attribute mapping for each string attribute in the collection where the source keyPath and the destination attribute property have the same name.
  • – mapAttributesFromArray:

    Defines an attribute mapping for each string attribute in the collection where the source keyPath and the destination attribute property have the same name.
  • – mapRelationship:withMapping:

    Defines a relationship mapping for a key where the source keyPath and the destination relationship property have the same name.
  • – hasMany:withMapping:

    Syntactic sugar to improve readability when defining a relationship mapping. Implies that the mapping targets a one-to-many relationship nested within the source data.
  • – hasOne:withMapping:

    Syntactic sugar to improve readability when defining a relationship mapping. Implies that the mapping targets a one-to-one relationship nested within the source data.
  • – mapKeyPath:toAttribute:

    Instantiate and add an RKObjectAttributeMapping instance targeting a keyPath within the mappable source data to an attribute on the target object.
  • – mapKeyPath:toRelationship:withMapping:

    Instantiate and add an RKObjectRelationshipMapping instance targeting a keyPath within the mappable source data to a relationship property on the target object.
  • – mapKeyPath:toRelationship:withMapping:serialize:

    Instantiate and add an RKObjectRelationshipMapping instance targeting a keyPath within the mappable source data to a relationship property on the target object.
  • – mapKeyPathsToAttributes:

    Quickly define a group of attribute mappings using alternating keyPath and attribute names. You must provide an equal number of keyPath and attribute pairs or an exception will be generated.
  • – mapKeyOfNestedDictionaryToAttribute:

    Configures a sub-key mapping for cases where JSON has been nested underneath a key named after an attribute.
  • – attributeMappingForKeyOfNestedDictionary

    Returns the attribute mapping targeting the key of a nested dictionary in the source JSON. This attribute mapping corresponds to the attributeName configured via mapKeyOfNestedDictionaryToAttribute:
  • – removeAllMappings

    Removes all currently configured attribute and relationship mappings from the object mapping
  • – removeMapping:

    Removes an instance of an attribute or relationship mapping from the object mapping
  • – removeMappingForKeyPath:

    Remove the attribute or relationship mapping for the specified source keyPath
  • – inverseMapping

    Generates an inverse mapping for the rules specified within this object mapping. This can be used to quickly generate a corresponding serialization mapping from a configured object mapping. The inverse mapping will have the source and destination keyPaths swapped for all attribute and relationship mappings.
  • – defaultValueForMissingAttribute:

    Returns the default value to be assigned to the specified attribute when it is missing from a mappable payload.
  • – mappableObjectForData:

    Returns an auto-released object that can be used to apply this object mapping given a set of mappable data. For transient objects, this generally returns an instance of the objectClass. For Core Data backed persistent objects, mappableData will be inspected to search for primary key data to lookup existing object instances.
  • – classForProperty:

    Returns the class of the attribute or relationship property of the target objectClass

DateAndTimeFormatting Methods

  • + defaultDateFormatters

    Returns the collection of default date formatters that will be used for all object mappings that have not been configured specifically.
  • + setDefaultDateFormatters:

    Sets the collection of default date formatters to the specified array. The array should contain configured instances of NSDateFormatter in the order in which you want them applied during object mapping operations.
  • + addDefaultDateFormatter:

    Adds a date formatter instance to the default collection
  • + addDefaultDateFormatterForString:inTimeZone:

    Convenience method for quickly constructing a date formatter and adding it to the collection of default date formatters. The locale is auto-configured to en_US_POSIX
  • + preferredDateFormatter

    Returns the preferred date formatter to use when generating NSString representations from NSDate attributes. This type of transformation occurs when RestKit is mapping local objects into JSON or form encoded serializations that do not have a native time construct.
  • + setPreferredDateFormatter:

    Sets the preferred date formatter to use when generating NSString representations from NSDate attributes. This type of transformation occurs when RestKit is mapping local objects into JSON or form encoded serializations that do not have a native time construct.

Properties

attributeMappings

The collection of attribute mappings within this object mapping

@property (nonatomic, readonly) NSArray *attributeMappings

Declared In

RKObjectMapping.h

dateFormatters

An array of NSDateFormatter objects to use when mapping string values into NSDate attributes on the target objectClass. Each date formatter will be invoked with the string value being mapped until one of the date formatters does not return nil.

@property (nonatomic, retain) NSArray *dateFormatters

Discussion

Defaults to the application-wide collection of date formatters configured via: [RKObjectMapping setDefaultDateFormatters:]

See Also

Declared In

RKObjectMapping.h

forceCollectionMapping

Forces the mapper to treat the mapped keyPath as a collection even if it does not return an array or a set of objects. This permits mapping where a dictionary identifies a collection of objects.

@property (nonatomic, assign) BOOL forceCollectionMapping

Discussion

When enabled, each key/value pair in the resolved dictionary will be mapped as a separate entity. This is useful when you have a JSON structure similar to:

 { "users": 
    { 
        "blake": { "id": 1234, "email": "[email protected]" },
        "rachit": { "id": 5678", "email": "[email protected]" }
    }
 }

By enabling forceCollectionMapping, RestKit will map “blake” => attributes and “rachit” => attributes as independent objects. This can be combined with mapKeyOfNestedDictionaryToAttribute: to properly map these sorts of structures.

@default NO

Declared In

RKObjectMapping.h

mappedKeyPaths

The collection of mappable keyPaths that are defined within this object mapping. These keyPaths refer to keys within the source object being mapped (i.e. the parsed JSON payload).

@property (nonatomic, readonly) NSArray *mappedKeyPaths

Declared In

RKObjectMapping.h

mappings

The aggregate collection of attribute and relationship mappings within this object mapping

@property (nonatomic, readonly) NSArray *mappings

Declared In

RKObjectMapping.h

objectClass

The target class this object mapping is defining rules for

@property (nonatomic, assign) Class objectClass

Declared In

RKObjectMapping.h

performKeyValueValidation

When YES, RestKit will invoke key-value validation at object mapping time.

@property (nonatomic, assign) BOOL performKeyValueValidation

Discussion

Default: YES

Declared In

RKObjectMapping.h

preferredDateFormatter

The NSDateFormatter instance for your application’s preferred date and time configuration. This date formatter will be used when generating string representations of NSDate attributes (i.e. during serialization to URL form encoded or JSON format).

@property (nonatomic, retain) NSDateFormatter *preferredDateFormatter

Discussion

Defaults to the application-wide preferred date formatter configured via: [RKObjectMapping setPreferredDateFormatter:]

See Also

Declared In

RKObjectMapping.h

relationshipMappings

The collection of relationship mappings within this object mapping

@property (nonatomic, readonly) NSArray *relationshipMappings

Declared In

RKObjectMapping.h

rootKeyPath

The root keyPath for this object. When the object mapping is being used for serialization and a root keyPath has been defined, the serialized object will be nested under this root keyPath before being encoded for transmission to a remote system.

@property (nonatomic, retain) NSString *rootKeyPath

See Also

Declared In

RKObjectMapping.h

setDefaultValueForMissingAttributes

When YES, any attributes that have mappings defined but are not present within the source object will be set to nil, clearing any existing value.

@property (nonatomic, assign, getter=shouldSetDefaultValueForMissingAttributes) BOOL setDefaultValueForMissingAttributes

Declared In

RKObjectMapping.h

setNilForMissingRelationships

When YES, any relationships that have mappings defined but are not present within the source object will be set to nil, clearing any existing value.

@property (nonatomic, assign) BOOL setNilForMissingRelationships

Declared In

RKObjectMapping.h

Class Methods

addDefaultDateFormatter:

Adds a date formatter instance to the default collection

+ (void)addDefaultDateFormatter:(NSDateFormatter *)dateFormatter

Parameters

dateFormatter

An NSDateFormatter object to append to the end of the default formatters collection

See Also

Declared In

RKObjectMapping.h

addDefaultDateFormatterForString:inTimeZone:

Convenience method for quickly constructing a date formatter and adding it to the collection of default date formatters. The locale is auto-configured to en_US_POSIX

+ (void)addDefaultDateFormatterForString:(NSString *)dateFormatString inTimeZone:(NSTimeZone *)nilOrTimeZone

Parameters

dateFormatString

The dateFormat string to assign to the newly constructed NSDateFormatter instance

nilOrTimeZone

The NSTimeZone object to configure on the NSDateFormatter instance. Defaults to UTC time.

Return Value

A new NSDateFormatter will be appended to the defaultDateFormatters with the specified date format and time zone

Declared In

RKObjectMapping.h

defaultDateFormatters

Returns the collection of default date formatters that will be used for all object mappings that have not been configured specifically.

+ (NSArray *)defaultDateFormatters

Return Value

An array of NSDateFormatter objects used when mapping strings into NSDate attributes

Discussion

Out of the box, RestKit initializes the following default date formatters for you in the UTC time zone:

* yyyy-MM-dd'T'HH:mm:ss'Z'
* MM/dd/yyyy

Declared In

RKObjectMapping.h

mappingForClass:

Returns an object mapping for the specified class that is ready for configuration

+ (id)mappingForClass:(Class)objectClass

Declared In

RKObjectMapping.h

mappingForClass:block:

Returns an object mapping targeting the specified class. The RKObjectMapping instance will be yieled to the block so that you can perform on the fly configuration without having to obtain a reference variable for the mapping.

+ (id)mappingForClass:(Class)objectClass block:(void ( ^ ) ( RKObjectMapping *))block

Discussion

For example, consider we have a one-off request that will load a few attributes for our object. Using blocks, this is very succinct:

[[RKObjectManager sharedManager] postObject:self delegate:self block:^(RKObjectLoader* loader) {
    loader.objectMapping = [RKObjectMapping mappingForClass:[Person class] block:^(RKObjectMapping* mapping) {
        [mapping mapAttributes:@"email", @"first_name", nil];
    }];
}];

Declared In

RKObjectMapping.h

preferredDateFormatter

Returns the preferred date formatter to use when generating NSString representations from NSDate attributes. This type of transformation occurs when RestKit is mapping local objects into JSON or form encoded serializations that do not have a native time construct.

+ (NSDateFormatter *)preferredDateFormatter

Return Value

The preferred NSDateFormatter to use when serializing dates into strings

Discussion

Defaults to a date formatter configured for the UTC Time Zone with a format string of “yyyy-MM-dd HH:mm:ss Z”

Declared In

RKObjectMapping.h

serializationMapping

Returns an object mapping useful for configuring a serialization mapping. The object class is configured as NSMutableDictionary

+ (id)serializationMapping

Declared In

RKObjectMapping.h

serializationMappingWithBlock:

Returns serialization mapping for encoding a local object to a dictionary for transport. The RKObjectMapping instance will be yieled to the block so that you can perform on the fly configuration without having to obtain a reference variable for the mapping.

+ (id)serializationMappingWithBlock:(void ( ^ ) ( RKObjectMapping *))block

Discussion

For example, consider we have a one-off request within which we want to post a subset of our object data. Using blocks, this is very succinct:

- (BOOL)changePassword:(NSString*)newPassword error:(NSError**)error {
    if ([self validatePassword:newPassword error:error]) {
        self.password = newPassword;
        [[RKObjectManager sharedManager] putObject:self delegate:self block:^(RKObjectLoader* loader) {
            loader.serializationMapping = [RKObjectMapping serializationMappingWithBlock:^(RKObjectMapping* mapping) {
                [mapping mapAttributes:@"password", nil];
            }];
        }];
    }
}

Using the block forms we are able to quickly configure and send this request on the fly.

Declared In

RKObjectMapping.h

setDefaultDateFormatters:

Sets the collection of default date formatters to the specified array. The array should contain configured instances of NSDateFormatter in the order in which you want them applied during object mapping operations.

+ (void)setDefaultDateFormatters:(NSArray *)dateFormatters

Parameters

dateFormatters

An array of date formatters to replace the existing defaults

See Also

Declared In

RKObjectMapping.h

setPreferredDateFormatter:

Sets the preferred date formatter to use when generating NSString representations from NSDate attributes. This type of transformation occurs when RestKit is mapping local objects into JSON or form encoded serializations that do not have a native time construct.

+ (void)setPreferredDateFormatter:(NSDateFormatter *)dateFormatter

Parameters

dateFormatter

The NSDateFormatter to configured as the new preferred instance

Declared In

RKObjectMapping.h

Instance Methods

addAttributeMapping:

Add a configured attribute mapping to this object mapping

- (void)addAttributeMapping:(RKObjectAttributeMapping *)mapping

See Also

Declared In

RKObjectMapping.h

addRelationshipMapping:

Add a configured attribute mapping to this object mapping

- (void)addRelationshipMapping:(RKObjectRelationshipMapping *)mapping

See Also

Declared In

RKObjectMapping.h

attributeMappingForKeyOfNestedDictionary

Returns the attribute mapping targeting the key of a nested dictionary in the source JSON. This attribute mapping corresponds to the attributeName configured via mapKeyOfNestedDictionaryToAttribute:

- (RKObjectAttributeMapping *)attributeMappingForKeyOfNestedDictionary

Return Value

An attribute mapping for the key of a nested dictionary being mapped or nil

See Also

Declared In

RKObjectMapping.h

classForProperty:

Returns the class of the attribute or relationship property of the target objectClass

- (Class)classForProperty:(NSString *)propertyName

Parameters

propertyName

The name of the property we would like to retrieve the type of

Discussion

Given the name of a string property, this will return an NSString, etc.

Declared In

RKObjectMapping.h

defaultValueForMissingAttribute:

Returns the default value to be assigned to the specified attribute when it is missing from a mappable payload.

- (id)defaultValueForMissingAttribute:(NSString *)attributeName

Discussion

The default implementation returns nil for transient object mappings. On managed object mappings, the default value returned from the Entity definition will be used.

See Also

Declared In

RKObjectMapping.h

hasMany:withMapping:

Syntactic sugar to improve readability when defining a relationship mapping. Implies that the mapping targets a one-to-many relationship nested within the source data.

- (void)hasMany:(NSString *)keyPath withMapping:(id<RKObjectMappingDefinition>)objectOrDynamicMapping

Declared In

RKObjectMapping.h

hasOne:withMapping:

Syntactic sugar to improve readability when defining a relationship mapping. Implies that the mapping targets a one-to-one relationship nested within the source data.

- (void)hasOne:(NSString *)keyPath withMapping:(id<RKObjectMappingDefinition>)objectOrDynamicMapping

Declared In

RKObjectMapping.h

inverseMapping

Generates an inverse mapping for the rules specified within this object mapping. This can be used to quickly generate a corresponding serialization mapping from a configured object mapping. The inverse mapping will have the source and destination keyPaths swapped for all attribute and relationship mappings.

- (RKObjectMapping *)inverseMapping

Declared In

RKObjectMapping.h

mapAttributes:

Define an attribute mapping for one or more keyPaths where the source keyPath and destination attribute property have the same name.

- (void)mapAttributes:(NSString *)attributeKey, ...

Parameters

attributeKey

A key-value coding key corresponding to a value in the mappable source object and an attribute on the destination class that have the same name.

Discussion

For example, given the transformation from a JSON dictionary:

{"name": "My Name", "age": 28}

To a Person class with corresponding name & age properties, we could configure the attribute mappings via:

[mapping mapAttributes:@"name", @"age", nil];

Declared In

RKObjectMapping.h

mapAttributesFromArray:

Defines an attribute mapping for each string attribute in the collection where the source keyPath and the destination attribute property have the same name.

- (void)mapAttributesFromArray:(NSArray *)set

Parameters

array

An array of string attribute keyPaths to deifne mappings for

Discussion

For example, given the transformation from a JSON dictionary:

{"name": "My Name", "age": 28}

To a Person class with corresponding name & age properties, we could configure the attribute mappings via:

[mapping mapAttributesFromSet:[NSArray arrayWithObjects:@"name", @"age", nil]];

Declared In

RKObjectMapping.h

mapAttributesFromSet:

Defines an attribute mapping for each string attribute in the collection where the source keyPath and the destination attribute property have the same name.

- (void)mapAttributesFromSet:(NSSet *)set

Parameters

set

A set of string attribute keyPaths to deifne mappings for

Discussion

For example, given the transformation from a JSON dictionary:

{"name": "My Name", "age": 28}

To a Person class with corresponding name & age properties, we could configure the attribute mappings via:

[mapping mapAttributesFromSet:[NSSet setWithObjects:@"name", @"age", nil]];

Declared In

RKObjectMapping.h

mapKeyOfNestedDictionaryToAttribute:

Configures a sub-key mapping for cases where JSON has been nested underneath a key named after an attribute.

- (void)mapKeyOfNestedDictionaryToAttribute:(NSString *)attributeName

Discussion

For example, consider the following JSON:

 { "users": 
    { 
        "blake": { "id": 1234, "email": "[email protected]" },
        "rachit": { "id": 5678", "email": "[email protected]" }
    }
 }

We can configure our mappings to handle this in the following form:

RKObjectMapping* mapping = [RKObjectMapping mappingForClass:[User class]];
mapping.forceCollectionMapping = YES; // RestKit cannot infer this is a collection, so we force it
[mapping mapKeyOfNestedDictionaryToAttribute:@"firstName"];
[mapping mapFromKeyPath:@"(firstName).id" toAttribute:"userID"];
[mapping mapFromKeyPath:@"(firstName).email" toAttribute:"email"];
[[RKObjectManager sharedManager].mappingProvider setObjectMapping:mapping forKeyPath:@"users"];

Declared In

RKObjectMapping.h

mapKeyPath:toAttribute:

Instantiate and add an RKObjectAttributeMapping instance targeting a keyPath within the mappable source data to an attribute on the target object.

- (void)mapKeyPath:(NSString *)sourceKeyPath toAttribute:(NSString *)destinationAttribute

Parameters

sourceKeyPath

A key-value coding keyPath to fetch the mappable value from

destinationAttribute

The attribute name to assign the mapped value to

Discussion

Used to quickly define mappings where the source value is deeply nested in the mappable data or the source and destination do not have corresponding names.

Examples:

// We want to transform the name to something Cocoa-esque
[mapping mapKeyPath:@"created_at" toAttribute:@"createdAt"];
// We want to extract nested data and map it to a property
[mapping mapKeyPath:@"results.metadata.generated_on" toAttribute:@"generationTimestamp"];

See Also

Declared In

RKObjectMapping.h

mapKeyPath:toRelationship:withMapping:

Instantiate and add an RKObjectRelationshipMapping instance targeting a keyPath within the mappable source data to a relationship property on the target object.

- (void)mapKeyPath:(NSString *)sourceKeyPath toRelationship:(NSString *)destinationRelationship withMapping:(id<RKObjectMappingDefinition>)objectOrDynamicMapping

Parameters

sourceKeyPath

A key-value coding keyPath to fetch the mappable value from

destinationRelationship

The relationship name to assign the mapped value to

objectMapping

An object mapping to use when processing the nested objects

Discussion

Used to quickly define mappings where the source value is deeply nested in the mappable data or the source and destination do not have corresponding names.

Examples:

 // We want to transform the name to something Cocoa-esque
 [mapping mapKeyPath:@"best_friend" toRelationship:@"bestFriend" withObjectMapping:friendMapping];
 // We want to extract nested data and map it to a property
 [mapping mapKeyPath:@"best_friend.favorite_cat" toRelationship:@"bestFriendsFavoriteCat" withObjectMapping:catMapping];

See Also

Declared In

RKObjectMapping.h

mapKeyPath:toRelationship:withMapping:serialize:

Instantiate and add an RKObjectRelationshipMapping instance targeting a keyPath within the mappable source data to a relationship property on the target object.

- (void)mapKeyPath:(NSString *)relationshipKeyPath toRelationship:(NSString *)keyPath withMapping:(id<RKObjectMappingDefinition>)objectOrDynamicMapping serialize:(BOOL)serialize

Parameters

serialize

A boolean value indicating whether to include this relationship in serialization

destinationRelationship

The relationship name to assign the mapped value to

objectMapping

An object mapping to use when processing the nested objects

sourceKeyPath

A key-value coding keyPath to fetch the mappable value from

Discussion

Used to indicate whether the relationship should be included in serialization.

Declared In

RKObjectMapping.h

mapKeyPathsToAttributes:

Quickly define a group of attribute mappings using alternating keyPath and attribute names. You must provide an equal number of keyPath and attribute pairs or an exception will be generated.

- (void)mapKeyPathsToAttributes:(NSString *)sourceKeyPath, ...

Parameters

sourceKeyPath

A key-value coding key path to fetch a mappable value from

...

A nil-terminated sequence of strings alternating between source key paths and destination attributes

Discussion

For example:

[personMapping mapKeyPathsToAttributes:@"name", @"name", @"createdAt", @"createdAt", @"street_address", @"streetAddress", nil];

Declared In

RKObjectMapping.h

mapRelationship:withMapping:

Defines a relationship mapping for a key where the source keyPath and the destination relationship property have the same name.

- (void)mapRelationship:(NSString *)relationshipKey withMapping:(id<RKObjectMappingDefinition>)objectOrDynamicMapping

Parameters

relationshipKey

A key-value coding key corresponding to a value in the mappable source object and a property

on the destination class that have the same name.
objectOrDynamicMapping

An RKObjectMapping or RKObjectDynamic mapping to apply when mapping the relationship

Discussion

For example, given the transformation from a JSON dictionary:

{“name”: “My Name”, “age”: 28, “cat”: { “name”: “Asia” } }

To a Person class with corresponding ‘cat’ relationship property, we could configure the mappings via:

 RKObjectMapping* catMapping = [RKObjectMapping mappingForClass:[Cat class]];
 [personMapping mapRelationship:@"cat" withObjectMapping:catMapping];

Declared In

RKObjectMapping.h

mappableObjectForData:

Returns an auto-released object that can be used to apply this object mapping given a set of mappable data. For transient objects, this generally returns an instance of the objectClass. For Core Data backed persistent objects, mappableData will be inspected to search for primary key data to lookup existing object instances.

- (id)mappableObjectForData:(id)mappableData

Declared In

RKObjectMapping.h

mappingForAttribute:

Returns the attribute mapping targeting the specified attribute on the destination object

- (RKObjectAttributeMapping *)mappingForAttribute:(NSString *)attributeKey

Parameters

attributeKey

The name of the attribute we want to retrieve the mapping for

Declared In

RKObjectMapping.h

mappingForKeyPath:

Returns the attribute or relationship mapping for the given source keyPath.

- (id)mappingForKeyPath:(NSString *)sourceKeyPath

Parameters

sourceKeyPath

A keyPath within the mappable source object that is mapped to an attribute or relationship in this object mapping.

Declared In

RKObjectMapping.h

mappingForRelationship:

Returns the relationship mapping targeting the specified relationship on the destination object

- (RKObjectRelationshipMapping *)mappingForRelationship:(NSString *)relationshipKey

Parameters

relationshipKey

The name of the relationship we want to retrieve the mapping for

Declared In

RKObjectMapping.h

removeAllMappings

Removes all currently configured attribute and relationship mappings from the object mapping

- (void)removeAllMappings

Declared In

RKObjectMapping.h

removeMapping:

Removes an instance of an attribute or relationship mapping from the object mapping

- (void)removeMapping:(RKObjectAttributeMapping *)attributeOrRelationshipMapping

Parameters

attributeOrRelationshipMapping

The attribute or relationship mapping to remove

Declared In

RKObjectMapping.h

removeMappingForKeyPath:

Remove the attribute or relationship mapping for the specified source keyPath

- (void)removeMappingForKeyPath:(NSString *)sourceKeyPath

Parameters

sourceKeyPath

A key-value coding key path to remove the mappings for

Declared In

RKObjectMapping.h