The document outlines a presentation by Peter Friese on the features and capabilities of RestKit, a library for interacting with RESTful web services in iOS applications. It covers various challenges in data handling, such as connectivity and offline data access, and demonstrates how RestKit streamlines HTTP requests, object mapping, and Core Data integration. It further discusses practical examples, including making requests, handling responses, and utilizing object relationships in a structured manner.

1. Peter Friese, Zühlke Engineering
RestKit
From Zero to Hero that?!
What’s

2. Peter Friese
@peterfriese
peter.friese@zuehlke.com
xing.to/peter
http://peterfriese.de

3. What we will cover today
1 Challenges
2 How can RestKit help?
3 Demos!

4. Challenges...
Differe
nt Data F
ormats
ky Con nectivity
Fla
O ffline Data Access

5. How can RestKit help?
2

6. RestKit Features
Integrated HTTP Stack
Pluggable Parser
Object Mapping
Core Data Integration
UI Integration

7. Integrated HTTP Stack
✔ Base URLs
✔ Custom Headers
✔ Network Indicator
✔ Performing Requests
✔ Background Processing
✔ Authentication
✔ Request caching

8. Base URL
// create client
RKClient *client =
[RKClient clientWithBaseURL:@"http://github.org"];

9. Custom Headers
// send this field with each request
[client
setValue:
[[[UIDevice currentDevice] identifierForVendor] UUIDString]
forHTTPHeaderField:@"X-UDID"];

10. Network Indicator
client.requestQueue.showsNetworkActivityIndicatorWhenBusy = YES;

11. Network Indicator
client.requestQueue.showsNetworkActivityIndicatorWhenBusy = YES;

12. Perform Requests
- (IBAction)forkYou:(id)sender {
[[RKClient sharedClient]
get:@"https://github.com/fluidicon.png"
delegate:self];
}
- (void)request:(RKRequest *)request
didLoadResponse:(RKResponse *)response
{
if ([response isSuccessful]) {
UIImage *image =
[UIImage imageWithData:[response body]];
self.imageView.image = image;
}
}

13. Requests with Blocks
- (IBAction)forkYouWithBlocks
Bloc ks FTW
{
self.imageView.image = nil;
[[RKClient sharedClient]
get:@"http://github.com/fluidicon.png"
usingBlock:^(RKRequest *request)
{
[request setOnDidLoadResponse:^(RKResponse *response)
{
if (response.isSuccessful)
{
UIImage *image =
[UIImage imageWithData:response.body];
self.imageView.image = image;
}
}];
}];
}

14. Background Processing
[request setBackgroundPolicy:
RKRequestBackgroundPolicyContinue];
// do noth
ing
RKRequest
Backgroun
dP olicyNone
// cancel
request
RKRequest
Backgroun
dPolicyC ancel
// continu
e until ext
RKRequest ra time exp
Backgroun ires
dPolicyCon
tinue
// requeu
e upon app
RKRequest restart
Backgroun
dPolicyReq
ueue

15. Authentication
[client
setAuthenticationType:RKRequestAuthenticationTypeHTTPBasic];
n
au thenticatio
// disable ica tionTypeNo
ne
RKReque stAuthent
on
aut o negotiati
C onnection
// NSURL io nTypeHTT
P
tA uthenticat
RKReques
h
Basic Aut sic
// HTTP Ty peHTTPBa
ut hentication
R KRequestA
// OAuth 1.0 nTypeOAu
th
atio
t Authentic
RKReques
.0
/ / OAuth 2 nT ypeOAuth
2
u thenticatio
R KRequestA

16. Request caching
client.cachePolicy =
RKRequestCachePolicyLoadIfOffline |
RKRequestCachePolicyTimeout;
// don’t u
se request
RKRequest cache
CachePolic
yNone
// use ca
che if off
RKRequest line
CachePolic
yLoadIfOf
// in case fline
of an error
RKRequest
CachePolic
yLoadOnEr
// use ET ror
ags
RKRequest
CachePolic
yEtag
// if we’ve
got data st
RKRequest ored
CachePolic
yEnabled
// in case
of a timeo
RKRequest ut
CachePolic
yTimeout

17. Object Mapping
XML
(legacy)
JSON
(new and cool)

18. Object Mapping
Dep
rec
ate
XMLd
(legacy)
JSON
(new and cool)

19. Object Mapping
✔ Simple Object Mapping
✔ Mapping Relationships
✔ Inverse Mappings
✔ Serialization Mappings

20. Object Mapping

21. Object Mapping
->
No Ha
#
shmaps

22. Object Mapping
@interface GithubUser : NSObject
@property (strong, nonatomic)
NSNumber *id;
@property (strong, nonatomic)
NSString *name;
->
@property (strong, nonatomic)
NSString *location;
@property (strong, nonatomic)
NSString *followers;
@property (strong, nonatomic)
NSString *email;
@property (strong, nonatomic)
NSString *following;
@end

23. Object Mapping
@interface GithubUser : NSObject
@property (strong, nonatomic)
NSNumber *id;
@property (strong, nonatomic)
NSString *name;
->
@property (strong, nonatomic)
NSString *location;
@property (strong, nonatomic)
NSString *followers;
@property (strong, nonatomic)
NSString *email;
@property (strong, nonatomic)
NSString *following;
@end

24. Object Mapping
@interface GithubUser : NSObject
@property (strong, nonatomic)
{ NSNumber *id;
id: 232107, @property (strong, nonatomic)
name: "Peter Friese", NSString *name;
location: "Hamburg", @property (strong, nonatomic)
followers: 42, NSString *location;
email: “peter@peterfriese.de, @property (strong, nonatomic)
following: 36, NSString *followers;
} @property (strong, nonatomic)
NSString *email;
@property (strong, nonatomic)
NSString *following;
@end

25. Object Mapping
RKObjectMapping *objectMapping =
[RKObjectMapping mappingForClass:[GithubUser class]];
{ @interface GithubUser : NSObject
id: 232107,
name: "Peter Friese", @property (strong, nonatomic)
location: "Hamburg", NSNumber *id;
followers: 42, @property (strong, nonatomic)
email: “peter@peterfriese.de, NSString *name;
following: 36, @property (strong, nonatomic)
} NSString *location;
@property (strong, nonatomic)
NSString *followers;

26. Object Mapping
RKObjectMapping *objectMapping =
[RKObjectMapping mappingForClass:[GithubUser class]];
register mapping
for a class
{ @interface GithubUser : NSObject
id: 232107,
name: "Peter Friese", @property (strong, nonatomic)
location: "Hamburg", NSNumber *id;
followers: 42, @property (strong, nonatomic)
email: “peter@peterfriese.de, NSString *name;
following: 36, @property (strong, nonatomic)
} NSString *location;
@property (strong, nonatomic)
NSString *followers;

27. Object Mapping
RKObjectMapping *objectMapping =
[RKObjectMapping mappingForClass:[GithubUser class]];
[objectMapping mapKeyPath:@"id"
toAttribute:@"id"];
[objectMapping mapKeyPath:@"name"
toAttribute:@"name"]; register mapping
for a class
{ @interface GithubUser : NSObject
id: 232107,
name: "Peter Friese", @property (strong, nonatomic)
location: "Hamburg", NSNumber *id;
followers: 42, @property (strong, nonatomic)
email: “peter@peterfriese.de, NSString *name;
following: 36, @property (strong, nonatomic)
} NSString *location;
@property (strong, nonatomic)
NSString *followers;

28. Object Mapping
RKObjectMapping *objectMapping =
[RKObjectMapping mappingForClass:[GithubUser class]];
[objectMapping mapKeyPath:@"id"
toAttribute:@"id"];
[objectMapping mapKeyPath:@"name"
re coapping
gister m nfigur
mapclass e
toAttribute:@"name"];
for ping (KV
C)
{ @interface GithubUser : NSObject
id: 232107,
name: "Peter Friese", @property (strong, nonatomic)
location: "Hamburg", NSNumber *id;
followers: 42, @property (strong, nonatomic)
email: “peter@peterfriese.de, NSString *name;
following: 36, @property (strong, nonatomic)
} NSString *location;
@property (strong, nonatomic)
NSString *followers;

29. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
usingBlock:^(RKObjectLoader *loader) {
}];

30. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[loader setObjectMapping:self.mapping];
}];

31. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[loader setObjectMapping:self.mapping];
resource path
mapping,
as
defined p
reviously
}];

32. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[loader setObjectMapping:self.mapping];
[loader setOnDidLoadObject:^(id object) {
}];
[loader setOnDidFailWithError:^(NSError *error) {
}];
}];

33. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[loader setObjectMapping:self.mapping];
[loader setOnDidLoadObject:^(id object) {
happy case :-)
}];
[loader setOnDidFailWithError:^(NSError *error) {
}]; sad unhappy case :-(
}];

34. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[loader setObjectMapping:self.mapping];
[loader setOnDidLoadObject:^(id object) {
[self.root bindToObject:object];
[self.quickDialogTableView reloadData];
}];
[loader setOnDidFailWithError:^(NSError *error) {
}]; sad unhappy case :-(
}];

35. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[SVProgressHUD showWithStatus:@"Loading..."];
[loader setObjectMapping:self.mapping];
[loader setOnDidLoadObject:^(id object) {
[self.root bindToObject:object];
[self.quickDialogTableView reloadData];
[SVProgressHUD dismiss];
}];
[loader setOnDidFailWithError:^(NSError *error) {
[SVProgressHUD showErrorWithStatus:@"Problem loading user"];
}];
}];

36. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[SVProgressHUD showWithStatus:@"Loading..."];
[loader setObjectMapping:self.mapping];
[loader setOnDidLoadObject:^(id object) {
heads up
[self.root bindToObject:object];
[self.quickDialogTableView reloadData];
!
[SVProgressHUD dismiss];
}];
[loader setOnDidFailWithError:^(NSError *error) {
[SVProgressHUD showErrorWithStatus:@"Problem loading user"];
}];
}];

37. GETting Objects
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:
[NSString stringWithFormat:@"/users/%@", self.userName]
usingBlock:^(RKObjectLoader *loader) {
[SVProgressHUD showWithStatus:@"Loading..."];
[loader setObjectMapping:self.mapping];
[loader setOnDidLoadObject:^(id object) {
[self.root bindToObject:object];
[self.quickDialogTableView reloadData];
[SVProgressHUD dismiss];
}];
[loader setOnDidFailWithError:^(NSError *error) {
[SVProgressHUD showErrorWithStatus:@"Problem loading user"];
}];
}];

38. Mapping Relationships
RKObjectMapping *userMapping =
[RKObjectMapping mappingForClass:[GithubUser class]];
RKObjectMapping *issueMapping =
[RKObjectMapping mappingForClass:[GithubIssue class]];
[issueMapping mapKeyPath:@"user"
toRelationship:@"user"
withMapping:userMapping];
[
@interface GithubIssue : NSObject
{
"number": 1347,
@property NSNumber *number;
"title": "Found a bug",
@property NSString *title;
"user": {
@property GithubUser *user;
"login": "octocat",

39. Mapping Relationships
RKObjectMapping *userMapping =
[RKObjectMapping mappingForClass:[GithubUser class]];
RKObjectMapping *issueMapping =
[RKObjectMapping mappingForClass:[GithubIssue class]];
[issueMapping mapKeyPath:@"user"
toRelationship:@"user"
withMapping:userMapping];
[
@interface GithubIssue : NSObject
{
"number": 1347,
@property NSNumber *number;
"title": "Found a bug",
@property NSString *title;
"user": {
@property GithubUser *user;
"login": "octocat",

40. POSTing Objects
[[objectManager mappingProvider]
setObjectMapping:issueMapping forKeyPath:@""];
RKObjectMapping *issueSerializationMapping =
[issueMapping inverseMapping];
[[[RKObjectManager sharedManager] mappingProvider]
setSerializationMapping:issueSerializationMapping
forClass:[GithubIssue class]];
[[[RKObjectManager sharedManager] router]
routeClass:[GithubIssue class]
toResourcePath:@"/repos/:repouser/:repo/issues"
forMethod:RKRequestMethodPOST ];
[[[RKObjectManager sharedManager] router]
routeClass:[GithubIssue class]
toResourcePath:@"/repos/:repouser/:repo/issues/:number"];

41. POSTing Objects
1: Create new object
GithubIssue *issue = [[GithubIssue alloc] init];
2: ProvideInfos for RestKit router:
issue.repouser = repouser;
issue.repo = repo;
3: POST object:
[[RKObjectManager sharedManager]
postObject:issue usingBlock:^(RKObjectLoader *loader){
loader.onDidLoadResponse = ^(RKResponse *response) {
[self dismissViewControllerAnimated:YES completion:nil];
}
}];

42. Core Data Integration
Offline Data Access
Remember?

43. Core Data Integration
Change Mapped Objects
Add a Core Data Model
Register a Managed Object Store
Adjust Object Mappings
Adjust Object Creation
Fetch Data from DB / Backend

44. Change Mapped Objects
Header Header
@interface GithubUser @interface GithubUser
: NSObject : NSManagedObject
Module Module
@synthesize id; @dynamic id;
@synthesize login; @dynamic login;
@synthesize name; @dynamic name;
@synthesize company; @dynamic company;
@synthesize location; @dynamic location;
@synthesize blog; @dynamic blog;
@synthesize following; @dynamic following;
@synthesize followers; @dynamic followers;
@synthesize email; @dynamic email;

45. Add a Core Data Model

46. Add a Core Data Model
@interface GithubUser
: NSObject

47. Add a Core Data Model
@interface GithubUser
: NSObject
Keep in mind:
Assign respect
ive
classes to ma
naged
objects!

48. Register a Managed Object Store
// set up object manager
RKObjectManager *objectManager =
[RKObjectManager
objectManagerWithBaseURL:@"https://api.github.com"];
// set up backing data store
objectManager.objectStore =
[RKManagedObjectStore
objectStoreWithStoreFilename:@"github.sqlite"];

49. Adjust Object Mappings
RKObjectMapping *userMapping =
[RKObjectMapping mappingForClass:[GithubUser class]];
RKManagedObjectMapping *userMapping =
[RKManagedObjectMapping mappingForClass:[GithubUser class]
inManagedObjectStore:objectStore];

50. Adjust Object Creation
GithubIssue *issue = [[GithubIssue alloc] init];
GithubIssue *issue = [GithubIssue object];
+ (id)object {
lloc]
i d object = [[self a ty]
initWi t h E n t i t y :[ s e l f e n t i
ext:
insertIn toManagedObjectCont ead]];
ext c ontextForCurrentThr
[ NSManagedObjectCont
];
return [object autorelease
}

51. Fetch Data from DB / Backend
Online of offline?
if ([[RKObjectManager sharedManager] isOnline]) {
[self fetchDataFromRemote];
}
else {
[self fetchDataFromDataStore];
}
Offline - Fetch from DB
- (void)fetchDataFromDataStore {
NSFetchRequest *request =
[[[RKObjectManager sharedManager] mappingProvider]
fetchRequestForResourcePath:self.resourcePath];
self.repos = [GithubRepo objectsWithFetchRequest:request];
[self.tableView reloadData];
}

52. Fetch Data from DB / Backend
Online - Fetch from Backend
- (void)fetchDataFromRemote {
[[RKObjectManager sharedManager]
loadObjectsAtResourcePath:[self resourcePath]
usingBlock:^(RKObjectLoader *loader) {
[loader setOnDidLoadObjects:^(NSArray *objects) {
self.repos = objects;
[self.tableView reloadData];
}];
}];
}

53. Fetch Data from DB / Backend
Reconnect after offline
- (void)reachabilityChanged:(NSNotification*)notification {
RKReachabilityObserver* observer =
(RKReachabilityObserver*)[notification object];
if ([observer isNetworkReachable]) {
if (![self.view isHidden]) {
[self fetchDataFromRemote];
}
}
else {
if (![self.view isHidden]) {
[self fetchDataFromDataStore];
}
}
}

54. Sync Manager
https://github.com/RestKit/RestKit/pull/573

55. Seeding your DB
Generate seed
[RKManagedObjectSeeder
generateSeedDatabaseWithObjectManager:objectManager
fromFiles:@"repos.json", nil];
Import seed
RKManagedObjectStore *objectStore = [RKManagedObjectStore
objectStoreWithStoreFilename:@"github.sqlite"
usingSeedDatabaseName:@"seed_db.sqlite"
managedObjectModel:nil
delegate:nil];

56. Putting it All Together

57. Putting it All Together
Wait a minute - can we do this simpler?

58. RestKit UI
✔ Static Tables
✔ Networked Table
✔ Forms

59. RestKit UI - Networked Table
self.tableController =
[[RKObjectManager sharedManager]
fetchedResultsTableControllerForTableViewController:self];
self.tableController.resourcePath = [self resourcePath];

60. RestKit UI - Networked Table
self.tableController =
[[RKObjectManager sharedManager]
fetchedResultsTableControllerForTableViewController:self];
self.tableController.resourcePath = [self resourcePath];
Sorting
NSSortDescriptor *descriptor =
[NSSortDescriptor
sortDescriptorWithKey:@"createdAt"
ascending:NO];
self.tableController.sortDescriptors =
[NSArray arrayWithObject:descriptor];

61. RestKit UI - Networked Table
self.tableController =
[[RKObjectManager sharedManager]
fetchedResultsTableControllerForTableViewController:self];
self.tableController.resourcePath = [self resourcePath];
her nic e stuff
Ot
self.tableController.autoRefreshFromNetwork = YES;
self.tableController.pullToRefreshEnabled = YES;

62. RestKit UI - Cell Mapping
RKTableViewCellMapping *cellMapping =
[RKTableViewCellMapping cellMapping];
cellMapping.style = UITableViewCellStyleValue1;
[cellMapping
mapKeyPath:@"name"
toAttribute:@"textLabel.text"];
[cellMapping
mapKeyPath:@"openIssues"
toAttribute:@"detailTextLabel.text"];
[cellMapping
setAccessoryType:UITableViewCellAccessoryDisclosureIndicator];
[tableController mapObjectsWithClass:
[GithubRepo class]
toTableCellsWithMapping:cellMapping];

63. Thanks!
http://www.slideshare.net/peterfriese
hat litt le spot
Reme mber t
he firs t slide?
on t

64. Awesome Unicorn Coloring Slide

65. Anyway, Thanks!
Peter Friese
om
peter.friese@zuehlke.c
hlke Engineering Gm
bH
Available for cons
Zü
Am Sandtorkai 66 ulting,
20457 Hamburg projects, discuss
ing
+49 151 108 604 72 all things mobile
- and frosty bever
ages!
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