Rails: 解析请求参数时出错。 (HTTP 放置)

Rails: Error occurred while parsing request parameters. (HTTP PUT)

我创建了一个简单的 Rails 应用程序:

$ rails new server --database=postgresql
$ rails generate scaffold contact name address city zip phone
$ git init
$ git add .
$ git commit -m "initial"
$ rake db:create
$ rake db:migrate

然后我使用 AFNetworking 框架创建了一个 iOS 客户端。我以这种方式向数据库添加了新记录:

+ (void) add: (Contact *)contact block:(void (^)(NSError *error))block{
    NSDictionary *fields = @{@"name": contact.name,
                             @"address": contact.address,
                             @"city": contact.city,
                             @"zip": contact.zip,
                             @"phone": contact.phone
                             };

    NSDictionary *params = @{@"contact":fields,
                             @"commit":@"add Contact"};

    NSString *urlString = @"http://0.0.0.0:300/contacts/";

    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];

    manager.requestSerializer = [AFJSONRequestSerializer serializer];
    [manager.requestSerializer setValue:@"application/json" forHTTPHeaderField:@"Accept"];
    [manager.requestSerializer setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];

    [manager POST:urlString parameters:params success:^(AFHTTPRequestOperation *operation, id responseObject) {
        //.......
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        //......
    }];

}

然后我这样列出记录:

+ (void)list:(void (^)(NSArray *contacts, NSError *error))block{
    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];

    manager.requestSerializer = [AFJSONRequestSerializer serializer];
    [manager.requestSerializer setValue:@"application/json" forHTTPHeaderField:@"Accept"];
    [manager.requestSerializer setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];

    NSString *url = @"http://0.0.0.0:300/contacts/";
    [manager GET:url parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {
        NSMutableArray *mutableContacts = [NSMutableArray arrayWithCapacity:[responseObject count]];
        for(NSDictionary *item in responseObject) {
            Contact *contact = [[Contact alloc] initWithAttributes:item];
            [mutableContacts addObject:contact];
        }

    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        // .... 
    }];
}

当我尝试使用此代码更新记录时:

+ (void) update: (Contact *)contact block:(void (^)(NSError *error))block{
    NSDictionary *fields = @{@"name": contact.name,
                             @"address": contact.address,
                             @"city": contact.city,
                             @"zip": contact.zip,
                             @"phone": contact.phone
                             };

    NSDictionary *params = @{@"contact":fields,
                             @"commit":@"Update Contact"};


    // url example ==>> http://0.0.0.0:3000/contact/2.json
    NSString *urlString = contact.url;

    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];

    manager.requestSerializer = [AFHTTPRequestSerializer serializer];
    [manager.requestSerializer setValue:@"application/json" forHTTPHeaderField:@"Accept"];
    [manager.requestSerializer setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];

    [manager PUT:urlString parameters:params success:^(AFHTTPRequestOperation *operation, id responseObject) {
        if (block) {
            block(nil);
        }
        NSLog(@"JSON: %@", responseObject);
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Response:  %@", [operation description]) ;
        if (block) {
            block(error);
        }
        NSLog(@"Error: %@", error);
    }];
}

我收到这个错误:

Started PUT "/contacts/2.json" for 192.168.0.3 at 2015-02-03 16:16:05 -0200
Error occurred while parsing request parameters.
Contents:

commit=Update%20Contact&contact[address]=xxxxxxx&contact[city]=xxxxxxx&contact[name]=BLA%20BLA%20BLA&contact[phone]=xxxxxxx&contact[zip]=xxxxxxx

ActionDispatch::ParamsParser::ParseError (795: unexpected token at 'commit=Update%20Contact&contact[address]=xxxxxxx&contact[city]=xxxxxxx&contact[name]=BLA%20BLA%20BLA&contact[phone]=xxxxxxx&contact[zip]=xxxxxxx'):
  actionpack (4.1.7) lib/action_dispatch/middleware/params_parser.rb:53:in `rescue in parse_formatted_parameters'
  actionpack (4.1.7) lib/action_dispatch/middleware/params_parser.rb:32:in `parse_formatted_parameters'
  actionpack (4.1.7) lib/action_dispatch/middleware/params_parser.rb:23:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/flash.rb:254:in `call'
  rack (1.5.2) lib/rack/session/abstract/id.rb:225:in `context'
  rack (1.5.2) lib/rack/session/abstract/id.rb:220:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/cookies.rb:560:in `call'
  activerecord (4.1.7) lib/active_record/query_cache.rb:36:in `call'
  activerecord (4.1.7) lib/active_record/connection_adapters/abstract/connection_pool.rb:621:in `call'
  activerecord (4.1.7) lib/active_record/migration.rb:380:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
  activesupport (4.1.7) lib/active_support/callbacks.rb:82:in `run_callbacks'
  actionpack (4.1.7) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/reloader.rb:73:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/remote_ip.rb:76:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
  railties (4.1.7) lib/rails/rack/logger.rb:38:in `call_app'
  railties (4.1.7) lib/rails/rack/logger.rb:20:in `block in call'
  activesupport (4.1.7) lib/active_support/tagged_logging.rb:68:in `block in tagged'
  activesupport (4.1.7) lib/active_support/tagged_logging.rb:26:in `tagged'
  activesupport (4.1.7) lib/active_support/tagged_logging.rb:68:in `tagged'
  railties (4.1.7) lib/rails/rack/logger.rb:20:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/request_id.rb:21:in `call'
  rack (1.5.2) lib/rack/methodoverride.rb:21:in `call'
  rack (1.5.2) lib/rack/runtime.rb:17:in `call'
  activesupport (4.1.7) lib/active_support/cache/strategy/local_cache_middleware.rb:26:in `call'
  rack (1.5.2) lib/rack/lock.rb:17:in `call'
  actionpack (4.1.7) lib/action_dispatch/middleware/static.rb:84:in `call'
  rack (1.5.2) lib/rack/sendfile.rb:112:in `call'
  railties (4.1.7) lib/rails/engine.rb:514:in `call'
  railties (4.1.7) lib/rails/application.rb:144:in `call'
  rack (1.5.2) lib/rack/lock.rb:17:in `call'
  rack (1.5.2) lib/rack/content_length.rb:14:in `call'
  rack (1.5.2) lib/rack/handler/webrick.rb:60:in `service'
  /Users/gazollajunior/.rvm/rubies/ruby-2.1.4/lib/ruby/2.1.0/webrick/httpserver.rb:138:in `service'
  /Users/gazollajunior/.rvm/rubies/ruby-2.1.4/lib/ruby/2.1.0/webrick/httpserver.rb:94:in `run'
  /Users/gazollajunior/.rvm/rubies/ruby-2.1.4/lib/ruby/2.1.0/webrick/server.rb:295:in `block in start_thread'

我遵循了 List 和 add 方法中的相同模式,但更新不起作用。

我做错了什么?

这看起来一点也不像 json:

commit=Update%20Contact&contact[address]=xxxxxxx&contact[city]=xxxxxxx&contact[name]=BLA%20BLA%20BLA&contact[phone]=xxxxxxx&contact[zip]=xxxxxxx

这看起来不对:

manager.requestSerializer = [AFHTTPRequestSerializer serializer];
...
[manager.requestSerializer setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];

用 AFJSONRequestSerializer 替换 AFHTTPRequestSerializer