Add no-side effects version of navigateToAppLink:error: and navigate: (#245)

- Allows app to know the type of navigation that would result of calling
  BFAppLinkNavigation's navigateToAppLink:error: or navigate: without
  having any side effects
- Also adds a test to ensure same output as navigateToAppLink:error:
  without the side effects.

Author: biasedbit

Bolts/iOS/BFAppLinkNavigation.h

@@ -57,6 +57,12 @@ typedef NS_ENUM(NSInteger, BFAppLinkNavigationType) {
                                extras:(NSDictionary *)extras
                           appLinkData:(NSDictionary *)appLinkData;
 
+/*!
+ Creates an NSDictionary with the correct format for iOS callback URLs,
+ to be used as 'appLinkData' argument in the call to navigationWithAppLink:extras:appLinkData:
+ */
++ (NSDictionary *)callbackAppLinkDataForAppWithName:(NSString *)appName url:(NSString *)url;
+
 /*! Performs the navigation */
 - (BFAppLinkNavigationType)navigate:(NSError **)error;
 
@@ -69,6 +75,20 @@ typedef NS_ENUM(NSInteger, BFAppLinkNavigationType) {
 /*! Navigates to a BFAppLink and returns whether it opened in-app or in-browser */
 + (BFAppLinkNavigationType)navigateToAppLink:(BFAppLink *)link error:(NSError **)error;
 
+/*!
+ Returns a BFAppLinkNavigationType based on a BFAppLink.
+ It's essentially a no-side-effect version of navigateToAppLink:error:,
+ allowing apps to determine flow based on the link type (e.g. open an
+ internal web view instead of going straight to the browser for regular links.)
+ */
++ (BFAppLinkNavigationType)navigationTypeForLink:(BFAppLink *)link;
+
+/*!
+ Return navigation type for current instance.
+ No-side-effect version of navigate:
+ */
+- (BFAppLinkNavigationType)navigationType;
+
 /*! Navigates to a URL (an asynchronous action) and returns a BFNavigationType */
 + (BFTask *)navigateToURLInBackground:(NSURL *)destination;
 

Bolts/iOS/BFAppLinkNavigation.m

@@ -20,6 +20,9 @@
 FOUNDATION_EXPORT NSString *const BFAppLinkUserAgentKeyName;
 FOUNDATION_EXPORT NSString *const BFAppLinkExtrasKeyName;
 FOUNDATION_EXPORT NSString *const BFAppLinkVersionKeyName;
+FOUNDATION_EXPORT NSString *const BFAppLinkRefererAppLink;
+FOUNDATION_EXPORT NSString *const BFAppLinkRefererAppName;
+FOUNDATION_EXPORT NSString *const BFAppLinkRefererUrl;
 
 static id<BFAppLinkResolving> defaultResolver;
 
@@ -43,6 +46,10 @@ + (instancetype)navigationWithAppLink:(BFAppLink *)appLink
     return navigation;
 }
 
++ (NSDictionary *)callbackAppLinkDataForAppWithName:(NSString *)appName url:(NSString *)url {
+    return @{BFAppLinkRefererAppLink: @{BFAppLinkRefererAppName: appName, BFAppLinkRefererUrl: url}};
+}
+
 - (NSString *)stringByEscapingQueryString:(NSString *)string {
 #if __IPHONE_OS_VERSION_MIN_REQUIRED >= __IPHONE_7_0 || __MAC_OS_X_VERSION_MIN_REQUIRED >= __MAC_10_9
     return [string stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];
@@ -229,6 +236,40 @@ + (BFAppLinkNavigationType)navigateToAppLink:(BFAppLink *)link error:(NSError **
                                            appLinkData:nil] navigate:error];
 }
 
++ (BFAppLinkNavigationType)navigationTypeForLink:(BFAppLink *)link {
+    return [[self navigationWithAppLink:link extras:nil appLinkData:nil] navigationType];
+}
+
+- (BFAppLinkNavigationType)navigationType {
+    BFAppLinkTarget *eligibleTarget = nil;
+    for (BFAppLinkTarget *target in self.appLink.targets) {
+        if ([[UIApplication sharedApplication] canOpenURL:target.URL]) {
+            eligibleTarget = target;
+            break;
+        }
+    }
+
+    if (eligibleTarget != nil) {
+        NSURL *appLinkURL = [self appLinkURLWithTargetURL:eligibleTarget.URL error:nil];
+        if (appLinkURL != nil) {
+            return BFAppLinkNavigationTypeApp;
+        } else {
+            return BFAppLinkNavigationTypeFailure;
+        }
+    }
+
+    if (self.appLink.webURL != nil) {
+        NSURL *appLinkURL = [self appLinkURLWithTargetURL:eligibleTarget.URL error:nil];
+        if (appLinkURL != nil) {
+            return BFAppLinkNavigationTypeBrowser;
+        } else {
+            return BFAppLinkNavigationTypeFailure;
+        }
+    }
+
+    return BFAppLinkNavigationTypeFailure;
+}
+
 + (id<BFAppLinkResolving>)defaultResolver {
     if (defaultResolver) {
         return defaultResolver;

BoltsTestUI/BoltsTestUI-Info.plist

@@ -39,6 +39,10 @@
 			</array>
 		</dict>
 	</array>
+	<key>LSApplicationQueriesSchemes</key>
+	<array>
+		<string>bolts</string>
+	</array>
 	<key>CFBundleVersion</key>
 	<string>1.0</string>
 	<key>LSRequiresIPhoneOS</key>

BoltsTests/AppLinkTests.m

@@ -756,6 +756,19 @@ - (void)testPlatformFiltering {
 
 #pragma mark App link navigation
 
+- (void)testSimpleAppLinkNavigationLookup {
+    BFAppLinkTarget *target = [BFAppLinkTarget appLinkTargetWithURL:[NSURL URLWithString:@"bolts://"]
+                                                         appStoreId:@"12345"
+                                                            appName:@"Bolts"];
+    BFAppLink *appLink = [BFAppLink appLinkWithSourceURL:[NSURL URLWithString:@"http://www.example.com/path"]
+                                                 targets:@[target]
+                                                  webURL:[NSURL URLWithString:@"http://www.example.com/path"]];
+    BFAppLinkNavigationType navigationType = [BFAppLinkNavigation navigationTypeForLink:appLink];
+
+    XCTAssertEqual(navigationType, BFAppLinkNavigationTypeApp);
+    XCTAssertEqual((NSUInteger)0, openedUrls.count); // no side effects
+}
+
 - (void)testSimpleAppLinkNavigation {
     BFAppLinkTarget *target = [BFAppLinkTarget appLinkTargetWithURL:[NSURL URLWithString:@"bolts://"]
                                                          appStoreId:@"12345"