够快网盘支持与iOS-ASIHTTPRequest框架学习
够快网盘支持与iOS-ASIHTTPRequest框架学习
前段时间在公司的产品中支持了够快网盘，用于云盘存储。
在这个过程中，学习到了很多新的知识，也遇到了很多问题，在此记录一下。
首先就够快的API总结一下。
一、请求参数中的签名。第一点是生成字符串，例如”2\n3\n1”，在C#中是不需要加上@前置符号的，这是我一个同事犯过的错误。第二点是签名算法，按照原文提示：将生成的字符利用client_secret作为key进行hmac-sha1加密，然后再进行base64 encode，最后对结果进行rfc3986 URL编码，即：encodeURI(base64_encode(hmac-sha1([string], [client_secret])))。OC的代码如下：
- (NSString*)getRequestSign:(NSString*)string { const char *cString = [string cStringUsingEncoding:NSUTF8StringEncoding]; const char *cSecret = [kCHRISGoKuaiClientSecret cStringUsingEncoding:NSUTF8StringEncoding]; char cHMAC[CC_SHA1_DIGEST_LENGTH]; CCHmac(kCCHmacAlgSHA1, cSecret, strlen(cSecret), cString, strlen(cString), cHMAC); NSData *HMAC = [[NSData alloc] initWithBytes:cHMAC length:CC_SHA1_DIGEST_LENGTH]; NSString *hash = [HMAC base64Encoding]; [HMAC release]; NSString *sign = (NSString*)CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (CFStringRef)hash, NULL, (CFStringRef)@"!*'();:@&=+$,/?%#[]", kCFStringEncodingUTF8); return sign; }
在此，需要先添加头文件引用：
#import <CommonCrypto/CommonHMAC.h>和#import <CommonCrypto/CommonCryptor.h>
二、删除和上传api中的路径参数。对象若为文件，则api中路径参数需要去掉首尾的”/”符号；对象若为文件夹，则api中需要在上述基础上，再在末尾加上一个”/”符号。
保存access_token。
在得到用户的access_token、expires_in、refresh_token以后，可以保存到设备端，避免繁琐的登陆授权操作。采用NSUserDefaults是不安全的，证书和密码之类的私密信息需要更为安全的keychain来保存。封装的keychain如下：
#import <Foundation/Foundation.h> @interface CHRISKeyChain : NSObject @property (readwrite, nonatomic, retain) NSDictionary* keyChainDic; + (id)keyChainForId:(NSString*)keyChainId; - (NSDictionary *)credentials; - (void)setCredentials:(NSDictionary *)credentials; - (void)deleteCredentials; @end
#import "CHRISKeyChain.h" static NSMutableDictionary* g_keyChainDic = nil; @implementation CHRISKeyChain @synthesize keyChainDic = _keyChainDic; + (id)keyChainForId:(NSString*)keyChainId { if (!g_keyChainDic) { g_keyChainDic = [[NSMutableDictionary dictionary] retain]; } CHRISKeyChain* keyChainObject = [g_keyChainDic objectForKey:keyChainId]; if (!keyChainObject) { NSDictionary* keyChainDict = [NSDictionary dictionaryWithObjectsAndKeys: (id)kSecClassGenericPassword, (id)kSecClass, keyChainId, (id)kSecAttrService, nil]; keyChainObject = [[[CHRISKeyChain alloc] init] autorelease]; keyChainObject.keyChainDic = keyChainDict; [g_keyChainDic setObject:keyChainObject forKey:keyChainId]; return keyChainObject; } return keyChainObject; } - (void)dealloc { self.keyChainDic = nil; [super dealloc]; } - (NSDictionary *)credentials { NSMutableDictionary *searchDict = [NSMutableDictionary dictionaryWithDictionary:_keyChainDic]; [searchDict setObject:(id)kSecMatchLimitOne forKey:(id)kSecMatchLimit]; [searchDict setObject:(id)kCFBooleanTrue forKey:(id)kSecReturnAttributes]; [searchDict setObject:(id)kCFBooleanTrue forKey:(id)kSecReturnData]; NSDictionary *attrDict = nil; OSStatus status = SecItemCopyMatching((CFDictionaryRef)searchDict, (CFTypeRef *)&attrDict); [attrDict autorelease]; NSData *foundValue = [attrDict objectForKey:(id)kSecValueData]; if (status == noErr && foundValue) { return [NSKeyedUnarchiver unarchiveObjectWithData:foundValue]; } if (status != errSecItemNotFound) { NSLog(@"error reading stored credentials (%ld)", status); } return nil; } - (void)setCredentials:(NSDictionary *)credentials { NSData *credentialData = [NSKeyedArchiver archivedDataWithRootObject:credentials]; NSMutableDictionary *attrDict = [NSMutableDictionary dictionaryWithDictionary:_keyChainDic]; [attrDict setObject:credentialData forKey:(id)kSecValueData]; NSArray *version = [[[UIDevice currentDevice] systemVersion] componentsSeparatedByString:@"."]; if ([[version objectAtIndex:0] intValue] >= 4) { [attrDict setObject:(id)kSecAttrAccessibleWhenUnlocked forKey:(id)kSecAttrAccessible]; } OSStatus status = noErr; if ([self credentials]) { [attrDict removeObjectForKey:(id)kSecClass]; status = SecItemUpdate((CFDictionaryRef)_keyChainDic, (CFDictionaryRef)attrDict); } else { status = SecItemAdd((CFDictionaryRef)attrDict, NULL); } if (status != noErr) { NSLog(@"error saving credentials (%ld)", status); } } - (void)deleteCredentials { OSStatus status = SecItemDelete((CFDictionaryRef)_keyChainDic); if (status != noErr) { NSLog(@"error deleting credentials (%ld)", status); } } @end
够快网盘之ASIHTTPRequest框架。
既然是网盘，必然涉及文件上传和下载等网络请求，这里采用了ASIHTTPRequest框架来实现网络请求和文件的上传、下载。
一、够快网盘的下载api采用get方式：
ASIHTTPRequest* request = [ASIHTTPRequest requestWithURL: url]; [request setCompletionBlock:^{ NSDictionary* params = [request.responseString objectFromJSONString]; .... }]; [request setFailedBlock:^{…}]; [request setStartedBlock:^{…}]; [request setBytesReceivedBlock:^(unsigned long long size, unsigned long long total){ Meta.synProgress =( (double)request.totalBytesRead + request.partialDownloadSize) / total; }]; [request setDownloadDestinationPath: filePath]; [request setAllowCompressedResponse: NO]; [request setAllowResumeForFileDownloads: YES]; [request setShouldPresentCredentialsBeforeChallenge: YES]; [request setShowAccurateProress: YES]; [request startAsynchronous];
说明：url为NSURL对象；filePath为本地存储路径；BytesReceivedBlock可以用来显示当前下载进度的百分比。objectFromJSONString方法需要先添加JSONKit并引用头文件。
二、够快网盘的上传api步骤2采用了post multipart/form-data方式：
ASIFormDataRequest* request = [ASIHTTPRequest requestWithURL: url]; [request setPostValue: … forKey: …]; ….. [request setPostValue: @”file” forKey: @”filefield”]; request.requestMethod = @”POST”; [request addRequestHeader:@”Content-Type” value:@”Multipart/form-data”] [request setCompletionBlock:^{ NSDictionary* params = [request.responseString objectFromJSONString]; ….. }]; [request setFailedBlock:^{….}]; [request setStartedBlock:^{…..}]; [request setBytesReceivedBlock:^(unsigned long long size, unsigned long long total){ Meta.synProgress =( (double)request.totalBytesSent )/ total; }]; [request setDownloadDestinationPath: filePath]; [request setAllowCompressedResponse: NO]; [request setAllowResumeForFileDownloads: YES]; [request setShouldPresentCredentialsBeforeChallenge: YES]; [request setShowAccurateProress: YES]; [request setShouldStreamPostFromDisk: YES]； [request setFile: localPath withFileName: [meta.path lastPathComponent] andContentType: meta.contentType forKey: @”file”]; [request startAsynchronous];
说明：[request setPostValue: @”file” forKey: @”filefield”];中的value必须和后面的forKey一致，这也符合api最后一个参数的说明。
当然还有其他方面，比如之前删除和上传没有成功，但是状态码返回200，经过与够快的开发人员一番沟通，发现了这两个api的缺陷，现在已经完善了，不会再遇到。
通过对够快网盘的支持，我也进一步学习了iOS的网络编程，收获还是很多的。
