Start work on download cache

+//
+//  ASICacheDelegate.h
+//  Part of ASIHTTPRequest -> http://allseeing-i.com/ASIHTTPRequest
+//
+//  Created by Ben Copsey on 01/05/2010.
+//  Copyright 2010 All-Seeing Interactive. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+@class ASIHTTPRequest;
+
+typedef enum _ASICachePolicy {
+	ASIDefaultCachePolicy = 0,
+	ASIIgnoreCachePolicy = 1,
+	ASIReloadIfDifferentCachePolicy = 2,
+	ASIOnlyLoadIfNotCachedCachePolicy = 3,
+	ASIUseCacheIfLoadFailsCachePolicy = 4
+} ASICachePolicy;
+
+typedef enum _ASICacheStoragePolicy {
+	ASICacheForSessionDurationCacheStoragePolicy = 0,
+	ASICachePermanentlyCacheStoragePolicy = 1
+} ASICacheStoragePolicy;
+
+
+@protocol ASICacheDelegate <NSObject>
+
+@required
+- (BOOL)useDataFromCacheForRequest:(ASIHTTPRequest *)request;
+- (void)storeResponseForRequest:(ASIHTTPRequest *)request;
+- (NSDictionary *)cachedHeadersForRequest:(ASIHTTPRequest *)request;
+- (NSData *)cachedResponseDataForRequest:(ASIHTTPRequest *)request;
+- (NSString *)pathToCachedResponseDataForRequest:(ASIHTTPRequest *)request;
+- (void)clearCachedResponsesForStoragePolicy:(ASICacheStoragePolicy)cachePolicy;
+@end

+//
+//  ASIDownloadCache.h
+//  Part of ASIHTTPRequest -> http://allseeing-i.com/ASIHTTPRequest
+//
+//  Created by Ben Copsey on 01/05/2010.
+//  Copyright 2010 All-Seeing Interactive. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+#import "ASICacheDelegate.h"
+
+@interface ASIDownloadCache : NSObject <ASICacheDelegate> {
+	ASICachePolicy defaultCachePolicy;
+	ASICacheStoragePolicy defaultCacheStoragePolicy;
+	NSString *storagePath;
+	NSLock *accessLock;
+	BOOL shouldRespectCacheHeaders;
+}
++ (id)sharedCache;
++ (BOOL)serverAllowsResponseCachingForRequest:(ASIHTTPRequest *)request;
+
+@property (assign) ASICachePolicy defaultCachePolicy;
+@property (assign) ASICacheStoragePolicy defaultCacheStoragePolicy;
+@property (retain) NSString *storagePath;
+@property (retain) NSLock *accessLock;
+@property (assign) BOOL shouldRespectCacheHeaders;
+@end

@@ -18,6 +18,7 @@
 #import "ASIHTTPRequestConfig.h"
 #import "ASIHTTPRequestDelegate.h"
 #import "ASIProgressDelegate.h"
+#import "ASICacheDelegate.h"
 
 extern NSString *ASIHTTPRequestVersion;
 
@@ -389,6 +390,16 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 	
 	// Will be ASIHTTPRequestRunLoopMode for synchronous requests, NSDefaultRunLoopMode for all other requests
 	NSString *runLoopMode;
+	
+	// The download cache that will be used for this request (use [ASIHTTPRequest setDefaultCache:cache] to configure a default cache
+	id <ASICacheDelegate> downloadCache;
+	
+	// The cache policy that will be used for this request - See ASICacheDelegate.h for possible values
+	ASICachePolicy cachePolicy;
+	
+	// The cache storage policy that will be used for this request - See ASICacheDelegate.h for possible values
+	ASICacheStoragePolicy cacheStoragePolicy;
+
 }
 
 #pragma mark init / dealloc
@@ -399,6 +410,9 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 // Convenience constructor
 + (id)requestWithURL:(NSURL *)newURL;
 
++ (id)requestWithURL:(NSURL *)newURL usingCache:(id <ASICacheDelegate>)cache;
++ (id)requestWithURL:(NSURL *)newURL usingCache:(id <ASICacheDelegate>)cache andCachePolicy:(ASICachePolicy)policy;
+
 #pragma mark setup request
 
 // Add a custom header to the request
@@ -668,6 +682,11 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 
 #endif
 
+#pragma mark cache
+
++ (void)setDefaultCache:(id <ASICacheDelegate>)cache;
++ (id <ASICacheDelegate>)defaultCache;
+
 // Returns the maximum amount of data we can read as part of the current measurement period, and sleeps this thread if our allowance is used up
 + (unsigned long)maxUploadReadLength;
 
@@ -712,7 +731,7 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 @property (retain,readonly) NSString *proxyAuthenticationRealm;
 @property (retain) NSError *error;
 @property (assign,readonly) BOOL complete;
-@property (retain,readonly) NSDictionary *responseHeaders;
+@property (retain) NSDictionary *responseHeaders;
 @property (retain) NSMutableDictionary *requestHeaders;
 @property (retain) NSMutableArray *requestCookies;
 @property (retain,readonly) NSArray *responseCookies;
@@ -721,7 +740,7 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 @property (retain) NSDictionary *proxyCredentials;
 @property (assign,readonly) int responseStatusCode;
 @property (retain,readonly) NSString *responseStatusMessage;
-@property (retain,readonly) NSMutableData *rawResponseData;
+@property (retain) NSMutableData *rawResponseData;
 @property (assign) NSTimeInterval timeOutSeconds;
 @property (retain) NSString *requestMethod;
 @property (retain) NSMutableData *postBody;
@@ -766,4 +785,7 @@ extern unsigned long const ASIWWANBandwidthThrottleAmount;
 @property (assign) BOOL shouldUseRFC2616RedirectBehaviour;
 @property (assign, readonly) BOOL connectionCanBeReused;
 @property (retain, readonly) NSNumber *requestID;
+@property (assign) id <ASICacheDelegate> downloadCache;
+@property (assign) ASICachePolicy cachePolicy;
+@property (assign) ASICacheStoragePolicy cacheStoragePolicy;
 @end

@@ -23,7 +23,7 @@
 
 
 // Automatically set on build
-NSString *ASIHTTPRequestVersion = @"v1.6.2-8 2010-05-01";
+NSString *ASIHTTPRequestVersion = @"v1.6.2-9 2010-05-02";
 
 NSString* const NetworkRequestErrorDomain = @"ASIHTTPRequestErrorDomain";
 
@@ -121,6 +121,8 @@ static NSDate *throttleWakeUpTime = nil;
 // Run once in initalize to record at runtime whether we're on iPhone OS 2. When YES, a workaround for a type conversion bug in iPhone OS 2.2.x is applied in some places
 static BOOL isiPhoneOS2;
 
+static id <ASICacheDelegate> defaultCache = nil;
+
 // Private stuff
 @interface ASIHTTPRequest ()
 
@@ -151,10 +153,8 @@ static BOOL isiPhoneOS2;
 #endif
 
 @property (assign) BOOL complete;
-@property (retain) NSDictionary *responseHeaders;
 @property (retain) NSArray *responseCookies;
 @property (assign) int responseStatusCode;
-@property (retain) NSMutableData *rawResponseData;
 @property (retain, nonatomic) NSDate *lastActivityTime;
 @property (assign) unsigned long long contentLength;
 @property (assign) unsigned long long partialDownloadSize;
@@ -252,6 +252,7 @@ static BOOL isiPhoneOS2;
 	[self setDidReceiveDataSelector:@selector(request:didReceiveData:)];
 	[self setURL:newURL];
 	[self setCancelledLock:[[[NSRecursiveLock alloc] init] autorelease]];
+	[self setDownloadCache:[[self class] defaultCache]];
 	return self;
 }
 
@@ -260,6 +261,19 @@ static BOOL isiPhoneOS2;
 	return [[[self alloc] initWithURL:newURL] autorelease];
 }
 
++ (id)requestWithURL:(NSURL *)newURL usingCache:(id <ASICacheDelegate>)cache
+{
+	return [self requestWithURL:newURL usingCache:cache andCachePolicy:ASIDefaultCachePolicy];
+}
+
++ (id)requestWithURL:(NSURL *)newURL usingCache:(id <ASICacheDelegate>)cache andCachePolicy:(ASICachePolicy)policy
+{
+	ASIHTTPRequest *request = [[[self alloc] initWithURL:newURL] autorelease];
+	[request setDownloadCache:cache];
+	[request setCachePolicy:policy];
+	return request;
+}
+
 - (void)dealloc
 {
 	[statusTimer invalidate];
@@ -607,6 +621,10 @@ static BOOL isiPhoneOS2;
 		[self buildPostBody];
 	}
 	
+	if (![[self requestMethod] isEqualToString:@"GET"]) {
+		[self setDownloadCache:nil];
+	}
+	
 	// If we're redirecting, we'll already have a CFHTTPMessageRef
 	if (request) {
 		CFRelease(request);
@@ -780,6 +798,15 @@ static BOOL isiPhoneOS2;
 		return;
 	}
 	
+	// See if we should pull from the cache rather than fetching the data
+	if ([self downloadCache] && [self cachePolicy] == ASIOnlyLoadIfNotCachedCachePolicy) {
+		if ([[self downloadCache] useDataFromCacheForRequest:self]) {
+			[[self cancelledLock] unlock];
+			return;
+		}
+	}
+	
+	
 	[self requestStarted];
 	
 	[self setDownloadComplete:NO];
@@ -1545,6 +1572,17 @@ static BOOL isiPhoneOS2;
 		return;
 	}
 	
+	if ([self downloadCache] && [self cachePolicy] == ASIUseCacheIfLoadFailsCachePolicy) {
+		if ([[self downloadCache] useDataFromCacheForRequest:self]) {
+			[self markAsFinished];
+			if ([self mainRequest]) {
+				[[self mainRequest] markAsFinished];
+			}
+			return;
+		}
+	}
+	
+	
 	[self setError:theError];
 	
 	ASIHTTPRequest *failedRequest = self;
@@ -1598,6 +1636,17 @@ static BOOL isiPhoneOS2;
 	[self setResponseHeaders:(NSDictionary *)headerFields];
 
 	CFRelease(headerFields);
+	
+	if ([self downloadCache] && [self cachePolicy] == ASIReloadIfDifferentCachePolicy) {
+		if ([[self downloadCache] useDataFromCacheForRequest:self]) {
+			CFRelease(message);
+			[self cancelLoad];
+			[self markAsFinished];
+			return;
+		}
+	}
+	
+	
 	[self setResponseStatusCode:(int)CFHTTPMessageGetResponseStatusCode(message)];
 	[self setResponseStatusMessage:[(NSString *)CFHTTPMessageCopyResponseStatusLine(message) autorelease]];
 
@@ -2569,6 +2618,12 @@ static BOOL isiPhoneOS2;
 			
 		}
 	}
+	
+	// Save to the cache
+	if ([self downloadCache]) {
+		[[self downloadCache] storeResponseForRequest:self];
+	}
+	
 	[progressLock unlock];
 
 	
@@ -3001,6 +3056,7 @@ static BOOL isiPhoneOS2;
 	[[[self class] sessionCredentialsStore] removeAllObjects];
 	[sessionCredentialsLock unlock];
 	[[self class] setSessionCookies:nil];
+	[[[self class] defaultCache] clearCachedResponsesForStoragePolicy:ASICacheForSessionDurationCacheStoragePolicy];
 }
 
 #pragma mark gzip decompression
@@ -3617,6 +3673,18 @@ static BOOL isiPhoneOS2;
 #endif
 
 
++ (void)setDefaultCache:(id <ASICacheDelegate>)cache
+{
+	[defaultCache release];
+	defaultCache = [cache retain];
+}
+
++ (id <ASICacheDelegate>)defaultCache
+{
+	return defaultCache;
+}
+
+
 #pragma mark miscellany 
 
 + (BOOL)isiPhoneOS2
@@ -3761,4 +3829,7 @@ static BOOL isiPhoneOS2;
 @synthesize downloadComplete;
 @synthesize requestID;
 @synthesize runLoopMode;
+@synthesize downloadCache;
+@synthesize cachePolicy;
+@synthesize cacheStoragePolicy;
 @end