feat(WKWebview): Add shared process pool so cookies and localStorage are shared across webviews in iOS (#138)

* fix(WKWebview): [iOS] Add shared process pool so cookies and localStorage are shared across webviews (#68)

* Add optional shared process pool

BREAKING CHANGE: useSharedProcessPool prop is set to true by default. If you want the old behavior, please use useSharedProcessPool={false}

ios/RNCWKProcessPoolManager.h

+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <WebKit/WebKit.h>
+
+@interface RNCWKProcessPoolManager : NSObject
+
++ (instancetype) sharedManager;
+- (WKProcessPool *)sharedProcessPool;
+
+@end

ios/RNCWKProcessPoolManager.m

+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <Foundation/Foundation.h>
+#import "RNCWKProcessPoolManager.h"
+
+@interface RNCWKProcessPoolManager() {
+    WKProcessPool *_sharedProcessPool;
+}
+@end
+
+@implementation RNCWKProcessPoolManager
+
++ (id) sharedManager {
+    static RNCWKProcessPoolManager *_sharedManager = nil;
+    @synchronized(self) {
+        if(_sharedManager == nil) {
+            _sharedManager = [[super alloc] init];
+        }
+        return _sharedManager;
+    }
+}
+
+- (WKProcessPool *)sharedProcessPool {
+    if (!_sharedProcessPool) {
+        _sharedProcessPool = [[WKProcessPool alloc] init];
+    }
+    return _sharedProcessPool;
+}
+
+@end
+

ios/RNCWKWebView.h

 @protocol RNCWKWebViewDelegate <NSObject>
 
 - (BOOL)webView:(RNCWKWebView *)webView
-shouldStartLoadForRequest:(NSMutableDictionary<NSString *, id> *)request
+   shouldStartLoadForRequest:(NSMutableDictionary<NSString *, id> *)request
    withCallback:(RCTDirectEventBlock)callback;
 
 @end
 @property (nonatomic, assign) BOOL automaticallyAdjustContentInsets;
 @property (nonatomic, assign) BOOL hideKeyboardAccessoryView;
 @property (nonatomic, assign) BOOL allowsBackForwardNavigationGestures;
+@property (nonatomic, assign) BOOL useSharedProcessPool;
 @property (nonatomic, copy) NSString *userAgent;
 @property (nonatomic, assign) BOOL allowsLinkPreview;
 

ios/RNCWKWebView.m

 #import "RNCWKWebView.h"
 #import <React/RCTConvert.h>
 #import <React/RCTAutoInsetsProtocol.h>
+#import "RNCWKProcessPoolManager.h"
 #import <UIKit/UIKit.h>
 
 #import "objc/runtime.h"
   return _webkitAvailable;
 }
 
-
 - (instancetype)initWithFrame:(CGRect)frame
 {
   if ((self = [super initWithFrame:frame])) {
     };
 
     WKWebViewConfiguration *wkWebViewConfig = [WKWebViewConfiguration new];
+    if(self.useSharedProcessPool) {
+        wkWebViewConfig.processPool = [[RNCWKProcessPoolManager sharedManager] sharedProcessPool];
+    }
     wkWebViewConfig.userContentController = [WKUserContentController new];
     [wkWebViewConfig.userContentController addScriptMessageHandler: self name: MessageHanderName];
     wkWebViewConfig.allowsInlineMediaPlayback = _allowsInlineMediaPlayback;
 /**
 * alert
 */
-- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler 
-{ 
+- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler
+{
     UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"" message:message preferredStyle:UIAlertControllerStyleAlert];
     [alert addAction:[UIAlertAction actionWithTitle:@"Ok" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
         completionHandler();

ios/RNCWKWebViewManager.m

   view.bounces = json == nil ? true : [RCTConvert BOOL: json];
 }
 
+RCT_CUSTOM_VIEW_PROPERTY(useSharedProcessPool, BOOL, RNCWKWebView) {
+  view.useSharedProcessPool = json == nil ? true : [RCTConvert BOOL: json];
+}
+
 RCT_CUSTOM_VIEW_PROPERTY(scrollEnabled, BOOL, RNCWKWebView) {
   view.scrollEnabled = json == nil ? true : [RCTConvert BOOL: json];
 }

ios/RNCWebView.xcodeproj/project.pbxproj

 	objects = {
 
 /* Begin PBXBuildFile section */
+		3515965E21A3C86000623BFA /* RNCWKProcessPoolManager.m in Sources */ = {isa = PBXBuildFile; fileRef = 3515965D21A3C86000623BFA /* RNCWKProcessPoolManager.m */; };
 		E914DBF6214474710071092B /* RNCUIWebViewManager.m in Sources */ = {isa = PBXBuildFile; fileRef = E914DBF3214474710071092B /* RNCUIWebViewManager.m */; };
 		E914DBF7214474710071092B /* RNCUIWebView.m in Sources */ = {isa = PBXBuildFile; fileRef = E914DBF4214474710071092B /* RNCUIWebView.m */; };
 		E91B351D21446E6C00F9801F /* RNCWKWebViewManager.m in Sources */ = {isa = PBXBuildFile; fileRef = E91B351B21446E6C00F9801F /* RNCWKWebViewManager.m */; };
 
 /* Begin PBXFileReference section */
 		134814201AA4EA6300B7C361 /* libRNCWebView.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libRNCWebView.a; sourceTree = BUILT_PRODUCTS_DIR; };
+		3515965D21A3C86000623BFA /* RNCWKProcessPoolManager.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = RNCWKProcessPoolManager.m; sourceTree = "<group>"; };
+		3515965F21A3C87E00623BFA /* RNCWKProcessPoolManager.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = RNCWKProcessPoolManager.h; sourceTree = "<group>"; };
 		E914DBF2214474710071092B /* RNCUIWebView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RNCUIWebView.h; sourceTree = "<group>"; };
 		E914DBF3214474710071092B /* RNCUIWebViewManager.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RNCUIWebViewManager.m; sourceTree = "<group>"; };
 		E914DBF4214474710071092B /* RNCUIWebView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RNCUIWebView.m; sourceTree = "<group>"; };
 				E91B351C21446E6C00F9801F /* RNCWKWebView.m */,
 				E91B351921446E6C00F9801F /* RNCWKWebViewManager.h */,
 				E91B351B21446E6C00F9801F /* RNCWKWebViewManager.m */,
+				3515965D21A3C86000623BFA /* RNCWKProcessPoolManager.m */,
+				3515965F21A3C87E00623BFA /* RNCWKProcessPoolManager.h */,
 				134814211AA4EA7D00B7C361 /* Products */,
 			);
 			sourceTree = "<group>";
 				E914DBF7214474710071092B /* RNCUIWebView.m in Sources */,
 				E914DBF6214474710071092B /* RNCUIWebViewManager.m in Sources */,
 				E91B351E21446E6C00F9801F /* RNCWKWebView.m in Sources */,
+				3515965E21A3C86000623BFA /* RNCWKProcessPoolManager.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

js/WebView.ios.js

   static defaultProps = {
     useWebKit: true,
     originWhitelist: defaultOriginWhitelist,
+    useSharedProcessPool: true,
   };
 
   static isFileUploadSupported = async () => {
           this.props.mediaPlaybackRequiresUserAction
         }
         dataDetectorTypes={this.props.dataDetectorTypes}
+        useSharedProcessPool={this.props.useSharedProcessPool}
         allowsLinkPreview={this.props.allowsLinkPreview}
         {...nativeConfig.props}
       />

js/WebViewTypes.js

    * back-forward list navigations.
    */
   allowsBackForwardNavigationGestures?: ?boolean,
+  /**
+   * A Boolean value indicating whether WebKit WebView should be created using a shared
+   * process pool, enabling WebViews to share cookies and localStorage between each other.
+   * Default is true but can be set to false for backwards compatibility.
+   * @platform ios
+   */
+  useSharedProcessPool?: ?boolean,
   /**
    * The custom user agent string.
    */