fix: Add more server checks before loading urls or reloading (#211)

jcesarmobile · mlynch · commit 60eff2ff5986 · 2018-11-09T08:58:05.000-06:00
Add  more server ckecks before loading urls or reloading, also check for socket
diff --git a/src/ios/CDVWKWebViewEngine.m b/src/ios/CDVWKWebViewEngine.m
@@ -107,6 +107,7 @@ @interface CDVWKWebViewEngine ()
 @property (nonatomic, readwrite) CGRect frame;
 @property (nonatomic, strong) NSString *userAgentCreds;
 @property (nonatomic, assign) BOOL internalConnectionsOnly;
+
 @property (nonatomic, readwrite) NSString *CDV_LOCAL_SERVER;
 @end
 
@@ -353,6 +354,14 @@ - (void)pluginInitialize
      addObserver:self
      selector:@selector(onAppWillEnterForeground:)
      name:UIApplicationWillEnterForegroundNotification object:nil];
+    [[NSNotificationCenter defaultCenter]
+     addObserver:self
+     selector:@selector(onSocketError:)
+     name:@"socketUnknownError" object:nil];
+    [[NSNotificationCenter defaultCenter]
+     addObserver:self
+     selector:@selector(onSocketError:)
+     name:@"socketInUseError" object:nil];
 
     NSLog(@"Using Ionic WKWebView");
 
@@ -417,7 +426,11 @@ - (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(N
     if (context == KVOContext) {
         if (object == [self webView] && [keyPath isEqualToString: @"URL"] && [object valueForKeyPath:keyPath] == nil){
             NSLog(@"URL is nil. Reloading WKWebView");
-            [(WKWebView*)_engineWebView reload];
+            if ([self.webServer isRunning]) {
+                [(WKWebView*)_engineWebView reload];
+            } else {
+                [self loadErrorPage:nil];
+            }
         }
     } else {
         [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
@@ -426,11 +439,19 @@ - (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(N
 
 - (void)onAppWillEnterForeground:(NSNotification *)notification {
     if ([self shouldReloadWebView]) {
-        NSLog(@"%@", @"CDVWKWebViewEngine reloading!");
-        [(WKWebView*)_engineWebView reload];
+        if ([self.webServer isRunning]) {
+            NSLog(@"%@", @"CDVWKWebViewEngine reloading!");
+            [(WKWebView*)_engineWebView reload];
+        } else {
+            [self loadErrorPage:nil];
+        }
     }
 }
 
+- (void)onSocketError:(NSNotification *)notification {
+    [self loadErrorPage:nil];
+}
+
 - (BOOL)shouldReloadWebView
 {
     WKWebView* wkWebView = (WKWebView*)_engineWebView;
@@ -475,17 +496,25 @@ - (id)loadRequest:(NSURLRequest *)request
     if ([self.webServer isRunning]) {
         return [(WKWebView*)_engineWebView loadRequest:request];
     } else {
-        NSString* errorHtml = [NSString stringWithFormat:
-                               @"<html>"
-                               @"<head><title>Error</title></head>"
-                               @"   <div style='font-size:2em'>"
-                               @"       <p>The App Server is not running.</p>"
-                               @"       <p>Close other apps and try again.</p>"
-                               @"   </div>"
-                               @"</html>"
-                               ];
-        return [self loadHTMLString:errorHtml baseURL:request.URL];
+        return [self loadErrorPage:request];
+    }
+}
+
+- (id)loadErrorPage:(NSURLRequest *)request
+{
+    if (!request) {
+        request = [NSURLRequest requestWithURL:[NSURL URLWithString:self.CDV_LOCAL_SERVER]];
     }
+    NSString* errorHtml = [NSString stringWithFormat:
+                           @"<html>"
+                           @"<head><title>Error</title></head>"
+                           @"   <div style='font-size:2em'>"
+                           @"       <p><b>Error</b></p>"
+                           @"       <p>Unable to load app.</p>"
+                           @"   </div>"
+                           @"</html>"
+                           ];
+    return [self loadHTMLString:errorHtml baseURL:request.URL];
 }
 
 - (id)loadHTMLString:(NSString *)string baseURL:(NSURL*)baseURL
@@ -744,7 +773,11 @@ - (void)webView:(WKWebView*)theWebView didFailNavigation:(WKNavigation*)navigati
 
 - (void)webViewWebContentProcessDidTerminate:(WKWebView *)webView
 {
-    [webView reload];
+    if ([self.webServer isRunning]) {
+        [webView reload];
+    } else {
+        [self loadErrorPage:nil];
+    }
 }
 
 - (BOOL)defaultResourcePolicyForURL:(NSURL*)url
@@ -815,14 +848,19 @@ - (void) webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigat
 
 -(void)getServerBasePath:(CDVInvokedUrlCommand*)command
 {
-  [self.commandDelegate sendPluginResult:[CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsString:self.basePath]  callbackId:command.callbackId];
+    [self.commandDelegate sendPluginResult:[CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsString:self.basePath]  callbackId:command.callbackId];
 }
 
 -(void)setServerBasePath:(CDVInvokedUrlCommand*)command
 {
-  NSString * path = [command argumentAtIndex:0];
-  [self setServerPath:path];
-  [(WKWebView*)_engineWebView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:self.CDV_LOCAL_SERVER]]];
+    NSString * path = [command argumentAtIndex:0];
+    [self setServerPath:path];
+    NSURLRequest * request = [NSURLRequest requestWithURL:[NSURL URLWithString:self.CDV_LOCAL_SERVER]];
+    if ([self.webServer isRunning]) {
+        [(WKWebView*)_engineWebView loadRequest:request];
+    } else {
+        [self loadErrorPage:request];
+    }
 }
 
 -(void)setServerPath:(NSString *) path
diff --git a/src/ios/GCDWebServer/Core/GCDWebServer.m b/src/ios/GCDWebServer/Core/GCDWebServer.m
@@ -461,6 +461,7 @@ - (int)_createListeningSocket:(BOOL)useIPv6
         *error = GCDWebServerMakePosixError(errno);
       }
       GWS_LOG_ERROR(@"Failed binding %s listening socket: %s (%i)", useIPv6 ? "IPv6" : "IPv4", strerror(errno), errno);
+      [[NSNotificationCenter defaultCenter] postNotification:[NSNotification notificationWithName:@"socketInUseError" object:nil]];
       close(listeningSocket);
     }
 
@@ -713,20 +714,38 @@ - (BOOL)hasSocketError:(int)socket {
   int error = 0;
   socklen_t len = sizeof(error);
   int retval = getsockopt(socket, SOL_SOCKET, SO_ERROR, &error, &len);
-    
+
   if (retval != 0 ) {
     /* there was a problem getting the error code */
     GWS_LOG_ERROR(@"error getting socket error code: %s\n", strerror(retval));
     return YES;
   }
-   
+
   if (error != 0) {
     GWS_LOG_INFO(@"Socket error: %s on socket %d\n", strerror(error), socket);
     return YES;
   }
   return NO;
 }
 
+- (int)socketError:(int)socket {
+    int error = 0;
+    socklen_t len = sizeof(error);
+    int retval = getsockopt(socket, SOL_SOCKET, SO_ERROR, &error, &len);
+
+    if (retval != 0 ) {
+        /* there was a problem getting the error code */
+        GWS_LOG_ERROR(@"error getting socket error code: %s\n", strerror(retval));
+        return retval;
+    }
+
+    if (error != 0) {
+        GWS_LOG_INFO(@"Socket error: %s on socket %d\n", strerror(error), socket);
+        return error;
+    }
+    return 0;
+}
+
 - (void)_didEnterBackground:(NSNotification*)notification {
   GWS_DCHECK([NSThread isMainThread]);
   GWS_LOG_DEBUG(@"Did enter background");
@@ -744,8 +763,14 @@ - (void)_willEnterForeground:(NSNotification*)notification {
   }
  
   if ([self isRunning] && ([self hasSocketError:ipv4ListeningSocket] || [self hasSocketError:ipv6ListeningSocket])) {
-    [self _stop];
-    [self _start:nil];
+    // If error is -1 (unknown) its probably because of port being used by other app, so don't restart in this case as it will fail
+    if ([self socketError:ipv4ListeningSocket] != -1 && [self socketError:ipv6ListeningSocket] != -1) {
+      [self _stop];
+      [self _start:nil];
+    } else {
+      _options = nil;
+      [[NSNotificationCenter defaultCenter] postNotification:[NSNotification notificationWithName:@"socketUnknownError" object:nil]];
+    }
   }
 }
 
