iOS 利用JSPatch 添加热补丁功能

ios 由于苹果的审核政策，一旦上线后发现bug是件让人崩溃的事情

不过可以利用oc的runtime机制可以家用JSPatch动态的为工程打热补丁

下载地址：https://github.com/agelessman/JSPatch.git

如果不用cocoapods导入的话，不需要修改，如果拖到工程的，需要改头文件，

例如： #import “abc.h”

在appdelegate中添加类似下边的方法，写一个本地的属性记录补丁的版本号，如果文件存在，再调用

 - (void)hotfix {

     // 获得应用程序沙盒的Downloads文件夹路径

     QKYGuideAccount *guideAccount = [QKYAccountTool guideAccount];

     NSArray *arrDownloadPaths =  NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);
     NSString *loadPathsPath=[arrDownloadPaths objectAtIndex:];
     NSString *patchPath = [loadPathsPath stringByAppendingPathComponent:[NSString stringWithFormat:@"patch_%@.js",guideAccount.patchVersion.length ? guideAccount.patchVersion : @""]];
     NSFileManager *fileManager = [NSFileManager defaultManager];
     BOOL isdir = NO;
     if ([fileManager fileExistsAtPath:patchPath isDirectory:&isdir]) {
         [JPEngine startEngine];
         [JPEngine evaluateScript:[NSString stringWithContentsOfFile:patchPath encoding:NSUTF8StringEncoding error:nil]];
     };

     QKYLog(@"Downloads path: %@",patchPath);
 }

在控制器中添加下边的方法，目的就是发请求到服务器，获取是否更新，

    //处理热修复
     self.dataController = [[QKYListDataController alloc] init];
     [self.dataController getIsNeedHotfixResultWithSuccessBlock:^(QKYIsNeedHotfixResult *  _Nonnull success, BOOL last) {

         if (success.code.integerValue ==  && success.newpatch.integerValue == ) {// 现在补丁
             [self.dataController downloadpatchWithUrl:success.patchurl];
         }

     } errorMsgBlock:^(NSError * _Nullable error, id  _Nullable msgBody) {

     }];

     NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
     NSString *version            = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
     NSMutableDictionary *dicM = [NSMutableDictionary dictionary];
     [dicM setValue:@"" forKey:@"comefrom"];
     [dicM setValue:version forKey:@"patchappversion"];
     QKYGuideAccount *guide = [QKYAccountTool guideAccount];
     [dicM setValue:guide.patchVersion.length ? guide.patchVersion : @"" forKey:@"patchversion"];

需要说明的是这里的dataController 是一个模型，下载补丁的方法封装到了这个模型中

在下载的条件成熟的情况下，下载附件

 - (void)downloadpatchWithUrl:(NSString *)url {

     if (!url) return;

     NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];

     AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

     manager.responseSerializer = [AFHTTPResponseSerializer serializer];

     NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:url]];

     NSProgress *downloadProgress = nil;

     NSURLSessionDownloadTask *downloadTask = [manager downloadTaskWithRequest:request progress:&downloadProgress destination:^NSURL * _Nonnull(NSURL * _Nonnull targetPath, NSURLResponse * _Nonnull response) {

         NSURL *downloadURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];
         return [downloadURL URLByAppendingPathComponent:[NSString stringWithFormat:@"patch_%@.js",self.result.patchversion]];

     } completionHandler:^(NSURLResponse * _Nonnull response, NSURL * _Nullable filePath, NSError * _Nullable error) {

         if (error) {
             return ;
         }
         QKYGuideAccount *account = [QKYAccountTool guideAccount];
         account.patchVersion = self.result.patchversion;
         [QKYAccountTool saveGuideAccount:account];

         [appDelegate hotfix];

     }];

     [downloadTask resume];
 }

下载成功后保存最新的补丁号到本地属性中，调用JSPatch，让刚下载的代码生效

需要特别说明的是，加载补丁文件，是有顺序的，例如0，1，2 而且补丁文件中使用的是js的代码，

能够帮助我的功能：

1 修复导致崩溃的错误

2 替换原来的方法

3.添加新的方法

4 替换原来的界面

等等，更多功能，有待研究

有问题可以写评论哦，