[ios, macos] Expose the url session configuration object. (#13886)

The `MGLNetworkConfiguration` class was make public, and added `sessionConfiguration` property to let developers customize the `NSURLSessionConfiguration` object that is used to make HTTP requests in the SDK.

1 files changed, 40 insertions, 12 deletions

diff --git a/platform/darwin/src/MGLNetworkConfiguration.m b/platform/darwin/src/MGLNetworkConfiguration.m
index 61422f7caa..8262e7eea1 100644
--- a/platform/darwin/src/MGLNetworkConfiguration.m
+++ b/platform/darwin/src/MGLNetworkConfiguration.m
@@ -1,23 +1,51 @@
 #import "MGLNetworkConfiguration.h"
 
+@interface MGLNetworkConfiguration ()
+
+@property (strong) NSURLSessionConfiguration *sessionConfig;
+
+@end
+
 @implementation MGLNetworkConfiguration
 
 + (instancetype)sharedManager {
     static dispatch_once_t onceToken;
     static MGLNetworkConfiguration *_sharedManager;
-    void (^setupBlock)(void) = ^{
-        dispatch_once(&onceToken, ^{
-            _sharedManager = [[self alloc] init];
-        });
-    };
-    if (![[NSThread currentThread] isMainThread]) {
-        dispatch_sync(dispatch_get_main_queue(), ^{
-            setupBlock();
-        });
-    } else {
-        setupBlock();
-    }
+    dispatch_once(&onceToken, ^{
+        _sharedManager = [[self alloc] init];
+        _sharedManager.sessionConfiguration = nil;
+    });
+
     return _sharedManager;
 }
 
+- (void)setSessionConfiguration:(NSURLSessionConfiguration *)sessionConfiguration {
+    @synchronized (self) {
+        if (sessionConfiguration == nil) {
+            _sessionConfig = [self defaultSessionConfiguration];
+        } else {
+            _sessionConfig = sessionConfiguration;
+        }
+    }
+}
+
+- (NSURLSessionConfiguration *)sessionConfiguration {
+    NSURLSessionConfiguration *sessionConfig = nil;
+    @synchronized (self) {
+        sessionConfig = _sessionConfig;
+    }
+    return sessionConfig;
+}
+
+- (NSURLSessionConfiguration *)defaultSessionConfiguration {
+    NSURLSessionConfiguration* sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
+    
+    sessionConfiguration.timeoutIntervalForResource = 30;
+    sessionConfiguration.HTTPMaximumConnectionsPerHost = 8;
+    sessionConfiguration.requestCachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
+    sessionConfiguration.URLCache = nil;
+    
+    return sessionConfiguration;
+}
+
 @end