Reworked reachability initialization to support usage when there is n…

…o Internet connectivity.

* When the reachabilityObserver property of RKClient is nil, assume we have reachability
* When the baseURL configured contains an IP address or localhost, use hostname based reachability
* Else fall through to using Internet reachability if the user has not configured an observer directly

Code/Network/RKClient.m

@@ -24,6 +24,7 @@
 #import "../Support/RKAlert.h"
 #import "../Support/RKLog.h"
 #import "../Support/RKPathMatcher.h"
+#import "../Support/NSString+RestKit.h"
 
 // Set Logging Component
 #undef RKLogComponent
@@ -128,7 +129,6 @@ - (id)init {
 
         // Configure reachability and queue
         [self addObserver:self forKeyPath:@"reachabilityObserver" options:NSKeyValueObservingOptionNew | NSKeyValueObservingOptionOld context:nil];
-        self.reachabilityObserver = [RKReachabilityObserver reachabilityObserverForInternet];
         self.requestQueue = [RKRequestQueue requestQueue];
 
         [self addObserver:self forKeyPath:@"baseURL" options:NSKeyValueObservingOptionNew context:nil];
@@ -187,7 +187,7 @@ - (NSString *)cachePath {
 }
 
 - (BOOL)isNetworkReachable {
-	BOOL isNetworkReachable = NO;
+	BOOL isNetworkReachable = YES;
 	if (self.reachabilityObserver) {
 		isNetworkReachable = [self.reachabilityObserver isNetworkReachable];
 	}
@@ -277,14 +277,25 @@ - (void)reachabilityObserverDidChange:(NSDictionary *)change {
 }
 
 - (void)baseURLDidChange:(NSDictionary *)change {
-    NSString *newBaseURL = [change objectForKey:NSKeyValueChangeNewKey];
+    NSString *newBaseURLString = [change objectForKey:NSKeyValueChangeNewKey];
 
     // Don't crash if baseURL is nil'd out (i.e. dealloc)
-    if (! [newBaseURL isEqual:[NSNull null]]) {
+    if (! [newBaseURLString isEqual:[NSNull null]]) {
         // Configure a cache for the new base URL
         [_requestCache release];
         _requestCache = [[RKRequestCache alloc] initWithCachePath:[self cachePath]
                                                     storagePolicy:RKRequestCacheStoragePolicyPermanently];
+
+        // Determine reachability strategy (if user has not already done so)
+        if (self.reachabilityObserver == nil) {
+            NSURL *newBaseURL = [NSURL URLWithString:newBaseURLString];
+            NSString *hostName = [newBaseURL host];
+            if ([newBaseURLString isEqualToString:@"localhost"] || [hostName isIPAddress]) {
+                self.reachabilityObserver = [RKReachabilityObserver reachabilityObserverForHost:hostName];
+            } else {
+                self.reachabilityObserver = [RKReachabilityObserver reachabilityObserverForInternet];
+            }
+        }
     }
 }
 

Code/Support/NSString+RestKit.h

@@ -117,4 +117,12 @@
  */
 - (NSString *)MIMETypeForPathExtension;
 
+/**
+ Returns YES if the receiver contains a valid IP address
+ 
+ For example, @"127.0.0.1" and @"10.0.1.35" would return YES
+ while @"restkit.org" would return NO
+ */
+- (BOOL)isIPAddress;
+
 @end

Code/Support/NSString+RestKit.m

@@ -26,6 +26,8 @@
 #import "NSString+RestKit.h"
 #import "../Network/RKClient.h"
 #import "RKFixCategoryBug.h"
+#include <netdb.h>
+#include <arpa/inet.h>
 
 RK_FIX_CATEGORY_BUG(NSString_RestKit)
 
@@ -132,4 +134,11 @@ - (NSString *)MIMETypeForPathExtension {
     return nil;
 }
 
+- (BOOL)isIPAddress {
+    struct sockaddr_in sa;
+    char *hostNameOrIPAddressCString = (char *) [self UTF8String];
+    int result = inet_pton(AF_INET, hostNameOrIPAddressCString, &(sa.sin_addr));    
+    return (result != 0);
+}
+
 @end

Specs/Support/NSStringRestKitSpec.m

@@ -75,4 +75,11 @@ - (void)itShouldReturnTheMIMETypeForAPath {
     assertThat(MIMEType, is(equalTo(@"application/xml")));
 }
 
+- (void)itShouldKnowIfTheReceiverContainsAnIPAddress {
+    assertThatBool([@"127.0.0.1" isIPAddress], equalToBool(YES));
+    assertThatBool([@"173.45.234.197" isIPAddress], equalToBool(YES));
+    assertThatBool([@"google.com" isIPAddress], equalToBool(NO));
+    assertThatBool([@"just some random text" isIPAddress], equalToBool(NO));
+}
+
 @end