Cache fixes - compare headers when ASIReloadIfDifferentCachePolicy

Added starting point tests for ASIDownloadCache

+//
+//  ASIDownloadCacheTests.h
+//  Part of ASIHTTPRequest -> http://allseeing-i.com/ASIHTTPRequest
+//
+//  Created by Ben Copsey on 03/05/2010.
+//  Copyright 2010 All-Seeing Interactive. All rights reserved.
+//
+
+#import "ASITestCase.h"
+
+
+@interface ASIDownloadCacheTests : ASITestCase {
+
+}
+
+@end

+//
+//  ASIDownloadCacheTests.m
+//  Part of ASIHTTPRequest -> http://asi/ASIHTTPRequest
+//
+//  Created by Ben Copsey on 03/05/2010.
+//  Copyright 2010 All-Seeing Interactive. All rights reserved.
+//
+
+#import "ASIDownloadCacheTests.h"
+#import "ASIDownloadCache.h"
+#import "ASIHTTPRequest.h"
+
+@implementation ASIDownloadCacheTests
+
+- (void)testDownloadCache
+{
+	[[ASIDownloadCache sharedCache] clearCachedResponsesForStoragePolicy:ASICacheForSessionDurationCacheStoragePolicy];
+	[[ASIDownloadCache sharedCache] clearCachedResponsesForStoragePolicy:ASICachePermanentlyCacheStoragePolicy];
+	[[ASIDownloadCache sharedCache] setDefaultCachePolicy:ASIReloadIfDifferentCachePolicy];
+	
+	// Ensure a request without a download cache does not pull from the cache
+	ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/cache-away"]];
+	[request startSynchronous];
+	BOOL success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Used cached response when we shouldn't have");
+	
+	// Check a request isn't setting didUseCachedResponse when the data is not in the cache
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/cache-away"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Cached response should not have been available");	
+	
+	// Ensure the cache works
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/cache-away"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	success = [request didUseCachedResponse];
+	GHAssertTrue(success,@"Failed to use cached response");
+	
+	// Test respecting etag
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/content-always-new"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Used cached response when we shouldn't have");
+	
+	// Etag will be different on the second request
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/content-always-new"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Used cached response when we shouldn't have");
+	
+	// Test ignoring server headers
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/no-cache"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[[ASIDownloadCache sharedCache] setShouldRespectCacheControlHeaders:NO];
+	[request startSynchronous];
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/no-cache"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[[ASIDownloadCache sharedCache] setShouldRespectCacheControlHeaders:NO];
+	[request startSynchronous];
+	success = [request didUseCachedResponse];
+	GHAssertTrue(success,@"Failed to use cached response");
+	
+	// Test ASIOnlyLoadIfNotCachedCachePolicy
+	[[ASIDownloadCache sharedCache] setShouldRespectCacheControlHeaders:YES];
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/content-always-new"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[[ASIDownloadCache sharedCache] setDefaultCachePolicy:ASIOnlyLoadIfNotCachedCachePolicy];
+	[request startSynchronous];
+	success = [request didUseCachedResponse];
+	GHAssertTrue(success,@"Failed to use cached response");
+	
+	// Test clearing the cache
+	[[ASIDownloadCache sharedCache] clearCachedResponsesForStoragePolicy:ASICacheForSessionDurationCacheStoragePolicy];
+	
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/cache-away"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Cached response should not have been available");
+}
+
+- (void)testDefaultPolicy
+{
+	ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	BOOL success = ([request cachePolicy] == [[ASIDownloadCache sharedCache] defaultCachePolicy]);
+	GHAssertTrue(success,@"Failed to use the cache policy from the cache");
+	
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request setCachePolicy:ASIOnlyLoadIfNotCachedCachePolicy];
+	[request startSynchronous];
+	success = ([request cachePolicy] == ASIOnlyLoadIfNotCachedCachePolicy);
+	GHAssertTrue(success,@"Failed to use the cache policy from the cache");
+}
+
+- (void)testNoCache
+{
+	// Test default cache policy
+	[[ASIDownloadCache sharedCache] clearCachedResponsesForStoragePolicy:ASICacheForSessionDurationCacheStoragePolicy];
+	[[ASIDownloadCache sharedCache] setDefaultCachePolicy:ASIIgnoreCachePolicy];
+	ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	BOOL success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Data should not have been stored in the cache");	
+	
+	// Test request cache policy
+	[[ASIDownloadCache sharedCache] setDefaultCachePolicy:ASIDefaultCachePolicy];
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request setCachePolicy:ASIIgnoreCachePolicy];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request setDownloadCache:[ASIDownloadCache sharedCache]];
+	[request startSynchronous];
+	success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Data should not have been stored in the cache");
+	
+	// Test server no-cache headers
+	[[ASIDownloadCache sharedCache] clearCachedResponsesForStoragePolicy:ASICacheForSessionDurationCacheStoragePolicy];
+	NSArray *cacheHeaders = [NSArray arrayWithObjects:@"cache-control/no-cache",@"cache-control/no-store",@"pragma/no-cache",nil];
+	for (NSString *cacheType in cacheHeaders) {
+		NSString *url = [NSString stringWithFormat:@"http://asi/ASIHTTPRequest/tests/%@",cacheType];
+		request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:url]];
+		[request setDownloadCache:[ASIDownloadCache sharedCache]];
+		[request startSynchronous];
+		
+		request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:url]];
+		[request setDownloadCache:[ASIDownloadCache sharedCache]];
+		[request startSynchronous];
+		success = ![request didUseCachedResponse];
+		GHAssertTrue(success,@"Data should not have been stored in the cache");
+	}
+}
+
+- (void)testSharedCache
+{
+	[[ASIDownloadCache sharedCache] clearCachedResponsesForStoragePolicy:ASICacheForSessionDurationCacheStoragePolicy];
+	
+	// Make using the cache automatic
+	[ASIHTTPRequest setDefaultCache:[ASIDownloadCache sharedCache]];
+	ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request startSynchronous];
+	
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request startSynchronous];
+	BOOL success = [request didUseCachedResponse];
+	GHAssertTrue(success,@"Failed to use data cached in default cache");
+	
+	[ASIHTTPRequest setDefaultCache:nil];
+	request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"http://asi/ASIHTTPRequest/tests/the_great_american_novel_(abridged).txt"]];
+	[request startSynchronous];
+	success = ![request didUseCachedResponse];
+	GHAssertTrue(success,@"Should not have used data cached in default cache");
+	
+}
+
+@end

@@ -27,6 +27,7 @@ typedef enum _ASICacheStoragePolicy {
 
 @required
 - (ASICachePolicy)defaultCachePolicy;
+- (BOOL)isCachedDataCurrentForRequest:(ASIHTTPRequest *)request;
 - (void)storeResponseForRequest:(ASIHTTPRequest *)request;
 - (NSDictionary *)cachedHeadersForRequest:(ASIHTTPRequest *)request;
 - (NSData *)cachedResponseDataForRequest:(ASIHTTPRequest *)request;

@@ -14,7 +14,7 @@
 	ASICacheStoragePolicy defaultCacheStoragePolicy;
 	NSString *storagePath;
 	NSRecursiveLock *accessLock;
-	BOOL shouldRespectCacheHeaders;
+	BOOL shouldRespectCacheControlHeaders;
 }
 + (id)sharedCache;
 + (BOOL)serverAllowsResponseCachingForRequest:(ASIHTTPRequest *)request;
@@ -23,5 +23,5 @@
 @property (assign) ASICacheStoragePolicy defaultCacheStoragePolicy;
 @property (retain) NSString *storagePath;
 @property (retain) NSRecursiveLock *accessLock;
-@property (assign) BOOL shouldRespectCacheHeaders;
+@property (assign) BOOL shouldRespectCacheControlHeaders;
 @end

@@ -80,7 +80,7 @@ static NSString *permanentCacheFolder = @"PermanentStore";
 		return;
 	}
 	
-	if ([self shouldRespectCacheHeaders] && ![[self class] serverAllowsResponseCachingForRequest:request]) {
+	if ([self shouldRespectCacheControlHeaders] && ![[self class] serverAllowsResponseCachingForRequest:request]) {
 		[[self accessLock] unlock];
 		return;
 	}
@@ -287,5 +287,5 @@ static NSString *permanentCacheFolder = @"PermanentStore";
 @synthesize defaultCachePolicy;
 @synthesize defaultCacheStoragePolicy;
 @synthesize accessLock;
-@synthesize shouldRespectCacheHeaders;
+@synthesize shouldRespectCacheControlHeaders;
 @end

@@ -399,6 +399,9 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 	
 	// The cache storage policy that will be used for this request - See ASICacheDelegate.h for possible values
 	ASICacheStoragePolicy cacheStoragePolicy;
+	
+	// Will be true when the response was pulled from the cache rather than downloaded
+	BOOL didUseCachedResponse;
 
 }
 
@@ -788,4 +791,5 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 @property (assign) id <ASICacheDelegate> downloadCache;
 @property (assign) ASICachePolicy cachePolicy;
 @property (assign) ASICacheStoragePolicy cacheStoragePolicy;
+@property (assign, readonly) BOOL didUseCachedResponse;
 @end

@@ -23,7 +23,7 @@
 
 
 // Automatically set on build
-NSString *ASIHTTPRequestVersion = @"v1.6.2-11 2010-05-02";
+NSString *ASIHTTPRequestVersion = @"v1.6.2-12 2010-05-03";
 
 NSString* const NetworkRequestErrorDomain = @"ASIHTTPRequestErrorDomain";
 
@@ -192,6 +192,7 @@ static id <ASICacheDelegate> defaultCache = nil;
 @property (assign, nonatomic) BOOL downloadComplete;
 @property (retain) NSNumber *requestID;
 @property (assign, nonatomic) NSString *runLoopMode;
+@property (assign) BOOL didUseCachedResponse;
 @end
 
 
@@ -2460,6 +2461,11 @@ static id <ASICacheDelegate> defaultCache = nil;
 		[self readResponseHeaders];
 	}
 	
+	// If we've cancelled the load part way through (for example, after deciding to use a cached version)
+	if ([self complete]) {
+		return;
+	}
+	
 	// In certain (presumably very rare) circumstances, handleBytesAvailable seems to be called when there isn't actually any data available
 	// We'll check that there is actually data available to prevent blocking on CFReadStreamRead()
 	// So far, I've only seen this in the stress tests, so it might never happen in real-world situations.
@@ -2674,6 +2680,13 @@ static id <ASICacheDelegate> defaultCache = nil;
 		return NO;
 	}
 	
+	if ([self cachePolicy] == ASIReloadIfDifferentCachePolicy) {
+		if (![[self downloadCache] isCachedDataCurrentForRequest:self]) {
+			return NO;
+		}
+	}
+	
+	[self setDidUseCachedResponse:YES];
 	[self cancelLoad];
 	
 	ASIHTTPRequest *theRequest = self;
@@ -3872,4 +3885,5 @@ static id <ASICacheDelegate> defaultCache = nil;
 @synthesize downloadCache;
 @synthesize cachePolicy;
 @synthesize cacheStoragePolicy;
+@synthesize didUseCachedResponse;
 @end

@@ -313,6 +313,9 @@
 - (IBAction)reloadTableData:(id)sender
 {
 	[[self tableQueue] cancelAllOperations];
+	[self setRowData:[NSMutableArray array]];
+	[tableView reloadData];
+
 	[self setTableQueue:[ASINetworkQueue queue]];
 	[[ASIDownloadCache sharedCache] setDefaultCachePolicy:ASIOnlyLoadIfNotCachedCachePolicy];
 	
@@ -333,7 +336,6 @@
 
 - (void)tableViewDataFetchFinished:(ASIHTTPRequest *)request
 {
-	[self setRowData:[NSMutableArray array]];
 	NSXMLDocument *xml = [[[NSXMLDocument alloc] initWithData:[request responseData] options:NSXMLDocumentValidate error:nil] autorelease];
 	for (NSXMLElement *row in [[xml rootElement] elementsForName:@"row"]) {
 		NSMutableDictionary *rowInfo = [NSMutableDictionary dictionary];