Add request configuration block to allow customizing HTTP request

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## master
 * Add your own contributions to the next release on the line below this with your name.
+- [new] Added request configuration handler to allow customizing HTTP headers per request [#355](https://github.com/pinterest/PINRemoteImage/pull/355) [zachwaugh](https://github.com/zachwaugh)
 - [fixed] Moved storage of resume data to disk from memory. [garrettmoon](https://github.com/garrettmoon)
 - [fixed] Hopefully fixes crashes occuring in PINURLSessionManager on iOS 9. [garrettmoon](https://github.com/garrettmoon)
 

Source/Classes/PINRemoteImageManager.h

@@ -121,6 +121,16 @@ typedef void(^PINRemoteImageManagerAuthenticationChallengeCompletionHandler)(NSU
  */
 typedef void(^PINRemoteImageManagerAuthenticationChallenge)(NSURLSessionTask * __nullable task, NSURLAuthenticationChallenge * __nonnull challenge, PINRemoteImageManagerAuthenticationChallengeCompletionHandler __nullable aHandler);
 
+
+/**
+ Request configuration handler. Used to modify a network request before it is executed.
+ Useful for adding custom, per-request headers.
+
+ @param request The request about to be executed
+ */
+typedef NSURLRequest * _Nonnull(^PINRemoteImageManagerRequestConfigurationHandler)(NSURLRequest * __nonnull request);
+
+
 /**
  Handler called for many PINRemoteImage tasks providing the progress of the download.
 
@@ -192,6 +202,13 @@ typedef void(^PINRemoteImageManagerProgressDownload)(int64_t completedBytes, int
  */
 - (void)setValue:(nullable NSString *)value forHTTPHeaderField:(nullable NSString *)header;
 
+/**
+ Sets the Request Configuration Block.
+
+ @param configurationBlock A PINRemoteImageManagerRequestConfigurationHandler block.
+ */
+- (void)setRequestConfiguration:(nullable PINRemoteImageManagerRequestConfigurationHandler)configurationBlock;
+
 /**
  Set the Authentication Challenge Block.
 

Source/Classes/PINRemoteImageManager.m

@@ -121,6 +121,7 @@ @interface PINRemoteImageManager () <PINURLSessionManagerDelegate>
 @property (nonatomic, assign) float lowQualityBPSThreshold;
 @property (nonatomic, assign) BOOL shouldUpgradeLowQualityImages;
 @property (nonatomic, copy) PINRemoteImageManagerAuthenticationChallenge authenticationChallengeHandler;
+@property (nonatomic, copy) PINRemoteImageManagerRequestConfigurationHandler requestConfigurationHandler;
 @property (nonatomic, strong) NSMutableDictionary <NSString *, NSString *> *httpHeaderFields;
 #if DEBUG
 @property (nonatomic, assign) float currentBPS;
@@ -281,6 +282,16 @@ - (void)setValue:(nullable NSString *)value forHTTPHeaderField:(nullable NSStrin
     });
 }
 
+- (void)setRequestConfiguration:(PINRemoteImageManagerRequestConfigurationHandler)configurationBlock {
+    __weak typeof(self) weakSelf = self;
+    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+        typeof(self) strongSelf = weakSelf;
+        [strongSelf lock];
+            strongSelf.requestConfigurationHandler = configurationBlock;
+        [strongSelf unlock];
+    });
+}
+
 - (void)setAuthenticationChallenge:(PINRemoteImageManagerAuthenticationChallenge)challengeBlock {
     __weak typeof(self) weakSelf = self;
     dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
@@ -921,6 +932,10 @@ - (NSURLSessionDataTask *)downloadDataWithURL:(NSURL *)url
         request.allHTTPHeaderFields = headers;
     }
 
+    if (_requestConfigurationHandler) {
+        request = [_requestConfigurationHandler(request) mutableCopy];
+    }
+
     [NSURLProtocol setProperty:key forKey:PINRemoteImageCacheKey inRequest:request];
 
     __weak typeof(self) weakSelf = self;

Tests/PINRemoteImageTests.m

@@ -269,6 +269,33 @@ - (void)testCustomRequestHeaderIsAddedToImageRequests
     [self waitForExpectationsWithTimeout:[self timeoutTimeInterval] handler:nil];
 }
 
+- (void)testRequestConfigurationIsUsedForImageRequest
+{
+    XCTestExpectation *expectation = [self expectationWithDescription:@"Requestion configuration block was called image request"];
+    NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
+    configuration.HTTPAdditionalHeaders = @{ @"X-Custom-Header" : @"Custom Header Value" };
+
+    self.imageManager = [[PINRemoteImageManager alloc] initWithSessionConfiguration:configuration];
+    [self.imageManager setRequestConfiguration:^NSURLRequest * _Nonnull(NSURLRequest * _Nonnull request) {
+        NSMutableURLRequest *mutableRequest = [request mutableCopy];
+        [mutableRequest setValue:@"Custom Header 2 Value" forHTTPHeaderField:@"X-Custom-Header-2"];
+        return mutableRequest;
+    }];
+
+    self.imageManager.sessionManager.delegate = self;
+    [self.imageManager downloadImageWithURL:[self headersURL]
+                                    options:PINRemoteImageManagerDownloadOptionsNone
+                                 completion:^(PINRemoteImageManagerResult *result)
+     {
+         NSDictionary *headers = [[NSJSONSerialization JSONObjectWithData:self.data options:NSJSONReadingMutableContainers error:nil] valueForKey:@"headers"];
+         XCTAssert([headers[@"X-Custom-Header"] isEqualToString:@"Custom Header Value"]);
+         XCTAssert([headers[@"X-Custom-Header-2"] isEqualToString:@"Custom Header 2 Value"]);
+
+         [expectation fulfill];
+     }];
+    [self waitForExpectationsWithTimeout:[self timeoutTimeInterval] handler:nil];
+}
+
 - (void)testSkipFLAnimatedImageDownload
 {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Download animated image"];