I download asynchronously some object, I store it in array. Next for each object I download some coordinates with geocoding (it is also asynchronously), and update my database for each object with new parameters which is coordinate. My method looks like this:
- (void)downloadObjectsWithTitle:(NSString *)title andHandler:(void(^)(NSMutableDictionary *result))handler {
AFHTTPClient *httpClient = [[AFHTTPClient alloc] initWithBaseURL:url];
NSMutableURLRequest *request = [httpClient requestWithMethod:#"GET"
path:nil
parameters:nil];
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
[httpClient registerHTTPOperationClass:[AFHTTPRequestOperation class]];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
//I get here array of objects
//now for each object I want to download geocoding localization so i called another asynchronyous method getLocationWithTitle:andHandler;
for(int i = 0; i < resutArray.count; i++) {
[self downloadLocationWithString:[dictionary objectForKey:#"string"] andHandler:^(NSMutableDictionary *result) {
//update database;
}];
}
handler(dictionary);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
[operation start];
}
My question is how to downalod coordinates for each object and that fire:
handler(dictionary);
so wait for each coordinates download (for each object) before quit method (fire handler).
Thnaks for all sugestions.
Maintain a count of all the tasks. When it's zero you're done.
Assuming you're using dispatch_async in downloadLocationWithString: on a concurrent queue:
dispatch_barrier_async(queue, ^{
// will only be called after all the blocks submitted to queue have finished.
}];
(If you're using serial queue, simply call handler at the last line of the last block)
Try a global flag. set NO first. In download block, after download complete set flag to yes. You can check that flag.
Related
I am stuck in serially Execution of Afnetworking Operation. Currently I am able to get all the operations' response but those are not serially . I need to make it serial.
What I am doing is
for (int i = 0; i < myArray.count; i++) {
//Creating Soap Request
// Adding that SoapRequest to Operation
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
// On success I am parsing the response
// Parsing is executed here..
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
// Failure message
}
// If Network is reachable then adding the Operation in queue
[[PFAPIClient sharedClient] enqueueHTTPRequestOperation:operation];
// Adding the operation (For multiple execution of operations)
}
Thus the response I get is not serial . Please Help me out.
So How to get this response serially and parsing the response accordingly .. After successfully Parsing I have to display them..
You can either set maxConcurrentOperationCount of PFAPIClient's NSOperationQueue to 1 or you can use dependencies, e.g.:
AFHTTPRequestOperation *previousOperation = nil;
for (int i = 0; i < myArray.count; i++) {
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
[operation setCompletionBlockWithSuccess:... failure:...];
if (previousOperation) {
[operation addDependency:previousOperation];
}
[[PFAPIClient sharedClient] enqueueHTTPRequestOperation:operation];
previousOperation = operation;
}
It's too bad you have to do these sequentially, as you'll pay huge performance penalty, but if you have to do it, that's two ways to accomplish it.
I am using AFNetworking (2.3.1) to parse JSON data and display it in labels.
To do this, I am using setCompletionBlockWithSuccess which is declared in AFHTTPRequestOperation.h.
Three functions like this are being called on viewDidLoad, one looks like:
-(void)parse {
NSURL *url = [[NSURL alloc] initWithString:kURL];
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
operation.responseSerializer = [AFJSONResponseSerializer serializer];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"Parse Successful");
//Code for JSON Parameters and to display data
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"%#", [error localizedDescription]);
//Code for Failure Handling
}];
[operation start];
}
While this works like a charm, because it is being contained in a block request, this process continues throughout the application state. So when this data does not need to be displayed, the requests are still loading, and I am receiving memory warnings because of these blocks.
My question is, how can I stop, cancel, or pause these processes once I leave the View Controller that they are created on in order to save memory and data, or handle them appropriately?
Forgive me if this is an obvious answer, and I am just handling or creating blocks in a totally wrong way. I am new to both AFNetworking and Blocks, operations, async requests, and the like.
Thanks.
Assuming you have an AFHTTPRequestOperation object called operation:
[operation cancel];
This probably belongs in ViewWillDisappear.
And then inside your failure block (which will then be called) you can check to see if it failed because of an error or if you canceled it:
if ([operation isCancelled])
{
//I canceled it.
}
Update - a more concrete example of how to save a reference to the operation and cancel it when the view dissapears.
#interface myViewController ()
#property (strong, nonatomic) AFHTTPRequestOperation *parseOperation;
#end
#implementation myViewController
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
//no need to check to see if the operation is nil (because it never happened or it's complete) because
//messages sent to nil are ok.
[self.parseOperation cancel];
}
-(void)parse {
NSURL *url = [[NSURL alloc] initWithString:kURL];
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
//save the parse operation so we can cancel it later on if we need to
self.parseOperation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
self.parseOperation.responseSerializer = [AFJSONResponseSerializer serializer];
__weak myViewController *weakSelf = self;
[self.parseOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
//nil out the operation we saved earlier because now that it's finished we don't need to cancel it anymore
weakSelf.parseOperation = nil;
NSLog(#"Parse Successful");
//Code for JSON Parameters and to display data
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
if (!operation.isCancelled) {
NSLog(#"%#", [error localizedDescription]);
//Code for Failure Handling
}
}];
[self.parseOperation start];
}
As it turns out, the lack of stopping was stemming from a timer (that called the block request, or the function parse) that was not invalidated once the view disappears. Invalidating the timer on -(void)viewDidDisappear: fixed the problem.
I'm trying to figure out a way to download multiple images with AFNewtorking 2.0. I've read a lot of posts here in SO, but can't find the answer I'm looking for, hope you guys can help me.
The problem is that I want to know when all of the downloads finished and if all images where downloaded.
So I have an array with image URL's ant trying to do something like this.
for(NSString *photoUrlString in self.photos){
NSURL *url = [NSURL URLWithString:photoUrlString];
AFHTTPRequestOperation *requestOperation = [[AFHTTPRequestOperation alloc] initWithRequest:[NSURLRequest requestWithURL:url]];
requestOperation.responseSerializer = [AFImageResponseSerializer serializer];
[requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Image error: %#", error);
}];
[requestOperation start];
}
I've found some answers with putting these requests into a queue and setting max concurrent operations to 1. But don't know how that works really.
Any help is appreciated, thanks in advance!
for(Photo *photo in array){
//form the path where you want to save your downloaded image to
NSString *constPath = [photo imageFullPath];
//url of your photo
NSURL *url = [NSURL URLWithString:photo.serverPath];
AFHTTPRequestOperation *op = [[AFHTTPRequestOperation alloc] initWithRequest:[NSURLRequest requestWithURL:url]];
op.responseSerializer = [AFImageResponseSerializer serializer];
op.outputStream = [NSOutputStream outputStreamToFileAtPath:constPath append:NO];
op.queuePriority = NSOperationQueuePriorityLow;
[op setDownloadProgressBlock:^(NSUInteger bytesRead, long long totalBytesRead, long long totalBytesExpectedToRead){
}];
op.completionBlock = ^{
//do whatever you want with the downloaded photo, it is stored in the path you create in constPath
};
[requestArray addObject:op];
}
NSArray *batches = [AFURLConnectionOperation batchOfRequestOperations:requestArray progressBlock:^(NSUInteger numberOfFinishedOperations, NSUInteger totalNumberOfOperations) {
} completionBlock:^(NSArray *operations) {
//after all operations are completed this block is called
if (successBlock)
successBlock();
}];
[[NSOperationQueue mainQueue] addOperations:batches waitUntilFinished:NO];
Try this:
// _group, _queue are iVar variable
dispatch_group_t *_group = dispatch_group_create();
dispatch_queue_t *_queue = dispatch_queue_create("com.company.myqueue2", NULL);
// all files download
for(int i = 0 ; i < numberOfFileDownloads; i++){
dispatch_group_async(_group, _queue, ^{
// here is background thread;
// download file
});
}
// all files are download successfully, this method is called
dispatch_group_notify(_group, _queue, ^{
}
Check out +[AFURLConnectionOperation batchOfRequestOperations:progressBlock:completionBlock:]
Although it's not documented, implementation is self-explanatory. Also it allows you to monitor the progress.
You will need to have an array of HTTP operations prior to using this method (this is if you decided to stick to NSURLConnection-based implementation of AFNetworking).
I've got subclass of AFHTTPClient
The main idea is that i call all API through my singleton of AFHTTPClient subclass, and all requests goes through 1 points for error handling and HUD displaying.
This is entry point for every API calls:
-(void) makeRequestWithPath:(NSString*) path andParams:(NSDictionary*) params
success:(void (^)( id JSON, AFHTTPRequestOperation *operation)) success
failure:(void (^)( NSError *error)) failure
And i've got many methods for API calls something like that:
-(void) getListMainTreeWithSuccess:(void (^)( id JSON, AFHTTPRequestOperation *operation)) success
failure:(void (^)( NSError *error)) failure
{
[self makeRequestWithPath:#"objects/selectlist" andParams:nil success:^(id JSON, AFHTTPRequestOperation *operation) {
success(JSON,operation);
} failure:^(NSError *error) {
failure(error);
}];
}
This works just fine for my needs. But i faced problem that i need to make serial request in loop through my AFHTTPClient subclass and make some action when all of them are finished , I found method
-(void)enqueueBatchOfHTTPRequestOperationsWithRequests:(NSArray *)urlRequests
progressBlock:(void (^)(NSUInteger numberOfFinishedOperations, NSUInteger totalNumberOfOperations))progressBlock
completionBlock:(void (^)(NSArray *operations))completionBlock
which should solve my issue, but the problem is that i call all methods through AFHTTPClient and it's methods getPath: and postPath: and previous way forces me to rewrite everything and makes my subclass completely useless, because I need to add there NSArray of AFHTTPRequestoperation, which is not possible to construct or extract from my subclass and my methods. Previously i tried to use __block 's to synchronise requests with semaphore and something else but i failed to get what i need, please help me!
UPDATE:
It seems that it is not possible to even use enqueueBatchOfHTTPRequestOperations method (even with rewriting all my code) because this method needs array of http request operations, but it's not possible to construct POST request with them.
I solved this with an increment/decrement pending download system and tied the HUD to that.
[networkStatus beginNetworkActivity];
[client someRESTActionWithCompletion:^(id object, NSError *error) {
[networkStatus endNetworkActivity];
if (error) {
// Handle the error ...
}
if (![networkStatus hasNetworkActivity]) {
// All downloads have finished
}
}];
I keep the network status object separate which from the AFHTTPClient subclass, but it can be built into the client if that's what you want.
Network status keeps an internal counter. -beginNetworkActivity increments the counter, if the counter was 0, then it displays a HUD. -endNetworkActivity decrements the counter, if the counter becomes 0, then it dismisses the HUD. -hasNetworkActivity returns YES if the counter greater than 0.
Other Notes: I combine the success and failed callbacks into a single completion callback. I keep the network status logic separate from the client because sometime I'll use a singleton network status object, sometimes I'll use a created instance, sometimes I won't use one at all. It all depends on the needs to the higher level logic.
Again, as #MikePollard said, create AFHTTPRequestOperation using
[AFHHTPClient HTTPRequestOperationWithRequest:success:failure:]
For this method create NSURLRequest using (or use another one, pick which one is suitable for you). Here you can also specify, which method to use POST, GET or any other.
[AFHTTPClient requestWithMethod:
path:
parameters:]
After that save all operation to an NSArray, and schedule them using:
[AFHTTPClient enqueueBatchOfHTTPRequestOperationsWithRequests:
progressBlock:
completionBlock:]
Code example:
NSMutableArray *ops = [NSMutableArray new];
NSMutableURLRequest *request1 = [[AFHTTPClient sharedClient] requestWithMethod:#"GET"
path:#"MyEndpoint"
parameters:#{#"key1": #"value"}];
AFHTTPRequestOperation *op1 = [[AFHTTPClient sharedClient] HTTPRequestOperationWithRequest:request1
success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"Success!");
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Failure!");
}];
[ops addObject:op1];
NSMutableURLRequest *request2 = [[AFHTTPClient sharedClient] requestWithMethod:#"POST"
path:#"MyAnotherEndpoint"
parameters:#{#"key2": #(104)}];
AFHTTPRequestOperation *op2 = [[AFHTTPClient sharedClient] HTTPRequestOperationWithRequest:request2
success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"Success!");
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Failure!");
}];
[ops addObject:op2];
[[AFHTTPClient sharedClient] enqueueBatchOfHTTPRequestOperationsWithRequests:ops
progressBlock:^(NSUInteger numberOfFinishedOperations, NSUInteger totalNumberOfOperations) {
NSLog(#"numberOfFinishedOperations: %d totalNumberOfOperations %d",
numberOfFinishedOperations,
totalNumberOfOperations);
}
completionBlock:^(NSArray *operations) {
NSLog(#"All operation compelted!");
}];
So I'm rewriting an app for iOS 7 with AFNetworking 2.0 and I'm running into the issue of sending a batch of requests at once and tracking their progress. In the old AFNetworking there was the enqueueBatchOfHTTPRequestOperations:progressBlock:completionBlock: method on AFHTTPClient, this is clearly refactored out and I'm a bit confused on how to enqueue multiple requests.
I have created a subclass of AFHTTPSessionManager and I'm using the POST:... and GET:... methods to communicate with the server. But I can't find anything in the code and/or docs to enqueue multiple requests at once like with the old AFHTTPClient.
The only thing I can find is the undocumented batchOfRequestOperations:progressBlock:completionBlock: method on AFURLConnectionOperation, but that looks like the iOS 6 way of doing this.
Clearly I'm missing something in the new NSURLSession concept that I should use to batch requests or looking over a new AFNetworking feature. Hope someone can help me on the right track here!
tl;dr: How can I send a batch of requests with my AFHTTPSessionManager subclass?
Thanks Sendoa for the link to the GitHub issue where Mattt explains why this functionality is not working anymore. There is a clear reason why this isn't possible with the new NSURLSession structure; Tasks just aren't operations, so the old way of using dependencies or batches of operations won't work.
I've created this solution using a dispatch_group that makes it possible to batch requests using NSURLSession, here is the (pseudo-)code:
// Create a dispatch group
dispatch_group_t group = dispatch_group_create();
for (int i = 0; i < 10; i++) {
// Enter the group for each request we create
dispatch_group_enter(group);
// Fire the request
[self GET:#"endpoint.json"
parameters:nil
success:^(NSURLSessionDataTask *task, id responseObject) {
// Leave the group as soon as the request succeeded
dispatch_group_leave(group);
}
failure:^(NSURLSessionDataTask *task, NSError *error) {
// Leave the group as soon as the request failed
dispatch_group_leave(group);
}];
}
// Here we wait for all the requests to finish
dispatch_group_notify(group, dispatch_get_main_queue(), ^{
// Do whatever you need to do when all requests are finished
});
I want to look write something that makes this easier to do and discuss with Matt if this is something (when implemented nicely) that could be merged into AFNetworking. In my opinion it would be great to do something like this with the library itself. But I have to check when I have some spare time for that.
Just updating the thread... I had the same problem and after some researches I found some good solutions, but I decided to stick with this one:
I am using the project called Bolts. So, for the same sample above posted by #Mac_Cain13, it would be:
[[BFTask taskWithResult:nil] continueWithBlock:^id(BFTask *task) {
BFTask *task = [BFTask taskWithResult:nil];
for (int i = 0; i < 10; i++) {
task = [task continueWithBlock:^id(BFTask *task) {
return [self executeEndPointAsync];
}];
}
return task;
}] continueWithBlock:^id(BFTask *task) {
// Everything was executed.
return nil;
}];;
- (BFTask *) executeEndPointAsync {
BFTaskCompletionSource *task = [BFTaskCompletionSource taskCompletionSource];
[self GET:#"endpoint.json" parameters:nil
success:^(NSURLSessionDataTask *task, id responseObject) {
[task setResult:responseObject];
}
failure:^(NSURLSessionDataTask *task, NSError *error) {
[task setError:error];
}];
}];
return task.task;
}
Basically, it's stacking all of the tasks, waiting and unwrapping until there is no more tasks, and after everything is completed the last completion block is executed.
Another project that does the same thing is RXPromise, but for me the code in Bolts was more clear.
For request which can be post or get, you can use AFNetworking 2.0 for batch operation as firstly you need to create operation like this:
//Request 1
NSString *strURL = [NSString stringWithFormat:#"your url here"];
NSLog(#"scheduleurl : %#",strURL);
NSDictionary *dictParameters = your parameters here
NSMutableURLRequest *request = [[AFHTTPRequestSerializer serializer] requestWithMethod:#"POST" URLString:strURL parameters:dictParameters error: nil];
AFHTTPRequestOperation *operationOne = [[AFHTTPRequestOperation alloc] initWithRequest:request];
operationOne = [AFHTTPResponseSerializer serializer];
[operationOne setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject)
{
//do something on completion
}
failure:^(AFHTTPRequestOperation *operation, NSError *error)
{
NSLog(#"%#",[error description]);
}];
//Request 2
NSString *strURL1 = [NSString stringWithFormat:#"your url here"];
NSLog(#"scheduleurl : %#",strURL);
NSDictionary *dictParameters1 = your parameters here
NSMutableURLRequest *request1 = [[AFHTTPRequestSerializer serializer] requestWithMethod:#"POST" URLString:strURL1 parameters:dictParameters1 error: nil];
AFHTTPRequestOperation *operationTwo = [[AFHTTPRequestOperation alloc] initWithRequest:request1];
operationTwo = [AFHTTPResponseSerializer serializer];
[operationTwo setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject)
{
//do something on completion
}
failure:^(AFHTTPRequestOperation *operation, NSError *error)
{
NSLog(#"%#",[error description]);
}];
//Request more here if any
Now perform batch operation like this :
//Batch operation
//Add all operation here
NSArray *operations = [AFURLConnectionOperation batchOfRequestOperations:#[operationOne,operationTwo] progressBlock:^(NSUInteger numberOfFinishedOperations, NSUInteger totalNumberOfOperations)
{
NSLog(#"%i of %i complete",numberOfFinishedOperations,totalNumberOfOperations);
//set progress here
yourProgressView.progress = (float)numberOfFinishedOperations/(float)totalNumberOfOperations;
} completionBlock:^(NSArray *operations)
{
NSLog(#"All operations in batch complete");
}];
[[NSOperationQueue mainQueue] addOperations:operations waitUntilFinished:NO];
On AFNetworking 2.0, AFHTTPClient has been split on AFHTTPRequestOperationManager and AFHTTPSessionManager, so probably you could start with the first, which has operationQueue property.
Currently, NSURLSession tasks are not suitable for the same kind of patterns request operations use. See the answer from Mattt Thompson here regarding this issue.
Direct answer: if you need dependencies or batches, you'll still need to use request operations.