Allow Timeout caching and ETag caching to play nice with each other. Update the internal cache date when we get a 304 back.

Code/Network/RKRequest.m

@@ -439,6 +439,12 @@
 	}
 }
 
+- (void)updateInternalCacheDate {
+    NSDate* date = [NSDate date];
+    RKLogInfo(@"Updating cache date for request %@ to %@", self, date);
+    [self.cache setCacheDate:date forRequest:self];
+}
+
 - (void)didFinishLoad:(RKResponse*)response {
   	_isLoading = NO;
   	_isLoaded = YES;
@@ -450,6 +456,7 @@
 
 	if ((_cachePolicy & RKRequestCachePolicyEtag) && [response isNotModified]) {
 		finalResponse = [self loadResponseFromCache];
+        [self updateInternalCacheDate];
 	}
 
 	if (![response wasLoadedFromCache] && [response isSuccessful] && (_cachePolicy != RKRequestCachePolicyNone)) {
@@ -535,7 +542,8 @@
     if (_method == RKRequestMethodDELETE) {
         return nil;
     }
-    NSString* compositCacheKey = [NSString stringWithFormat:@"%@-%d-%@", self.URL, _method, [_URLRequest HTTPBody]];
+    // Use [_params HTTPBody] because the URLRequest body may not have been set up yet.
+    NSString* compositCacheKey = [NSString stringWithFormat:@"%@-%d-%@", self.URL, _method, [_params HTTPBody]];
     return [compositCacheKey MD5];
 }
 

Code/Network/RKRequestCache.h

@@ -50,6 +50,8 @@ typedef enum {
 
 - (NSDate*)cacheDateForRequest:(RKRequest*)request;
 
+- (void)setCacheDate:(NSDate*)date forRequest:(RKRequest*)request;
+
 - (void)invalidateRequest:(RKRequest*)request;
 
 - (void)invalidateWithStoragePolicy:(RKRequestCacheStoragePolicy)storagePolicy;

Code/Network/RKRequestCache.m

@@ -128,6 +128,19 @@ static NSDateFormatter* __rfc1123DateFormatter;
 	return hasEntryForRequest;
 }
 
+- (void)writeHeaders:(NSDictionary*)headers toCachePath:(NSString*)cachePath {
+    RKLogTrace(@"Writing headers to cache path: '%@'", cachePath);
+    BOOL success = [headers writeToFile:[cachePath
+                                         stringByAppendingPathExtension:headersExtension]
+                             atomically:YES];
+    if (success) {
+        RKLogTrace(@"Wrote cached response header to path '%@'", cachePath);
+        
+    } else {
+        RKLogError(@"Failed to write cached response headers to path '%@'", cachePath);
+    }
+}
+
 - (void)storeResponse:(RKResponse*)response forRequest:(RKRequest*)request {
 	[_cacheLock lock];
     
@@ -166,15 +179,7 @@ static NSDateFormatter* __rfc1123DateFormatter;
                 [headers setObject:[urlResponse.URL absoluteString]
 							forKey:cacheURLKey];
                 // Save
-                BOOL success = [headers writeToFile:[cachePath
-                                                     stringByAppendingPathExtension:headersExtension]
-                                         atomically:YES];
-                if (success) {
-                    RKLogTrace(@"Wrote cached response header to path '%@'", cachePath);
-                    
-                } else {
-                    RKLogError(@"Failed to write cached response headers to path '%@'", cachePath);
-                }
+                [self writeHeaders:headers toCachePath:cachePath];
 			}
             
 			[headers release];
@@ -245,6 +250,16 @@ static NSDateFormatter* __rfc1123DateFormatter;
 	return etag;
 }
 
+- (void)setCacheDate:(NSDate*)date forRequest:(RKRequest*)request {
+    NSMutableDictionary* responseHeaders = [[self headersForRequest:request] mutableCopy];
+    
+    [responseHeaders setObject:[[RKRequestCache rfc1123DateFormatter] stringFromDate:date]
+                                 forKey:cacheDateHeaderKey];
+    [self writeHeaders:responseHeaders toCachePath:[self pathForRequest:request]];
+    
+    [responseHeaders release];
+}
+
 - (NSDate*)cacheDateForRequest:(RKRequest*)request {
 	NSDate* date;
     NSString* dateString;

Code/ObjectMapping/RKObjectLoader.m

@@ -22,6 +22,10 @@
 #undef RKLogComponent
 #define RKLogComponent lcl_cRestKitNetwork
 
+@interface RKRequest (Private)
+- (void)updateInternalCacheDate;
+@end
+
 @implementation RKObjectLoader
 
 @synthesize objectManager = _objectManager, response = _response;
@@ -321,6 +325,7 @@
 		[_response release];
 		_response = nil;
 		_response = [[[[RKClient sharedClient] cache] responseForRequest:self] retain];
+        [self updateInternalCacheDate];
 	}
 
 	if (![_response wasLoadedFromCache] && [_response isSuccessful] && (_cachePolicy != RKRequestCachePolicyNone)) {

Specs/Network/RKRequestSpec.m

@@ -286,6 +286,54 @@
     }
 }
 
+- (void)itShouldUpdateTheInternalCacheDateWhenWeRecieveA304 {
+    RKLogConfigureByName("RestKit/Network", RKLogLevelTrace);
+    NSString* baseURL = RKSpecGetBaseURL();
+    NSString* cacheDirForClient = [NSString stringWithFormat:@"RKClientRequestCache-%@",
+								   [[NSURL URLWithString:baseURL] host]];
+	NSString* cachePath = [[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) objectAtIndex:0]
+						   stringByAppendingPathComponent:cacheDirForClient];
+    RKRequestCache* cache = [[RKRequestCache alloc] initWithCachePath:cachePath
+                                                        storagePolicy:RKRequestCacheStoragePolicyPermanently];
+    [cache invalidateWithStoragePolicy:RKRequestCacheStoragePolicyPermanently];
+    
+    NSDate* internalCacheDate1;
+    NSDate* internalCacheDate2;
+    {
+        RKSpecResponseLoader* loader = [RKSpecResponseLoader responseLoader];
+        NSString* url = [NSString stringWithFormat:@"%@/etags/cached", RKSpecGetBaseURL()];
+        NSURL* URL = [NSURL URLWithString:url];
+        RKRequest* request = [[RKRequest alloc] initWithURL:URL];
+        request.cachePolicy = RKRequestCachePolicyEtag;
+        request.cache = cache;
+        request.delegate = loader;
+        [request sendAsynchronously];
+        [loader waitForResponse];
+        [expectThat([loader success]) should:be(YES)];
+        [expectThat([loader.response bodyAsString]) should:be(@"This Should Get Cached")];
+        [expectThat([cache etagForRequest:request]) should:be(@"686897696a7c876b7e")];
+        [expectThat([loader.response wasLoadedFromCache]) should:be(NO)];
+        internalCacheDate1 = [cache cacheDateForRequest:request];
+    }
+    [[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1.5]];
+    {
+        RKSpecResponseLoader* loader = [RKSpecResponseLoader responseLoader];
+        NSString* url = [NSString stringWithFormat:@"%@/etags/cached", RKSpecGetBaseURL()];
+        NSURL* URL = [NSURL URLWithString:url];
+        RKRequest* request = [[RKRequest alloc] initWithURL:URL];
+        request.cachePolicy = RKRequestCachePolicyEtag;
+        request.cache = cache;
+        request.delegate = loader;
+        [request sendAsynchronously];
+        [loader waitForResponse];
+        [expectThat([loader success]) should:be(YES)];
+        [expectThat([loader.response bodyAsString]) should:be(@"This Should Get Cached")];
+        [expectThat([loader.response wasLoadedFromCache]) should:be(YES)];
+        internalCacheDate2 = [cache cacheDateForRequest:request];
+    }
+    [expectThat(internalCacheDate1) shouldNot:be(internalCacheDate2)];
+}
+
 - (void)itShouldLoadFromTheCacheIfThereIsAnError {
     NSString* baseURL = RKSpecGetBaseURL();
     NSString* cacheDirForClient = [NSString stringWithFormat:@"RKClientRequestCache-%@",
@@ -325,8 +373,6 @@
 }
 
 - (void)itShouldLoadFromTheCacheIfWeAreWithinTheTimeout {
-    RKLogConfigureByName("RestKit/Network", RKLogLevelTrace);
-    
     NSString* baseURL = RKSpecGetBaseURL();
     NSString* cacheDirForClient = [NSString stringWithFormat:@"RKClientRequestCache-%@",
 								   [[NSURL URLWithString:baseURL] host]];