iphone - 使用 Attachment_fu 将照片从 iPhone 上传到 Rails 服务器

Question

我想我已经能够使用 Multipart 格式将照片从 iPhone 发送到 Rails，但是一旦照片到达 Rails 服务器，我不知道如何正确保存它。我认为当调用 iphone_photo_to_website 时，该文件在 Rails 服务器上的参数中显示为“userfile”，位于下面的参数末尾:

Parameters: {"action"=>"iphone_photo_to_website","id"=>"8A39FA8F_1ADD_52AB_8387_E1C5CFC4AB2D", "controller"=>"users", "userfile"=>#<File:/tmp/RackMultipart30053-0>}

我使用以下 SO 问题中的 Objective-C 代码从 iPhone 发送照片:

How can I upload a photo to a server with the iPhone?

NSString *imagePath = [[NSBundle mainBundle] pathForResource:@"logo1" ofType:@"png"];
NSData *imageData   = [NSData dataWithContentsOfFile:imagePath];

NSString *urlString = [NSString stringWithFormat:@"%@/users/iphone_photo_to_website/%@",
                    serverString, UID];


NSMutableURLRequest *imageRequest = [[NSMutableURLRequest alloc] init] ;
[imageRequest setURL:[NSURL URLWithString:urlString]];
[imageRequest setHTTPMethod:@"POST"];
NSString *boundary = [NSString stringWithString:@"---------------------------14737809831466499882746641449"];
NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
[imageRequest setValue:contentType forHTTPHeaderField: @"Content-Type"];
NSMutableData *body = [NSMutableData dataWithCapacity:[imageData length] + 512];
[body appendData:[[NSString stringWithFormat:@"--%@\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]]; 
[body appendData:[[NSString stringWithString:@"Content-Disposition: form-data; name=\"userfile\"; filename=\"logo1.png\"\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[NSData dataWithData:imageData]];
[body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[imageRequest setHTTPBody:body];

theConnection = [[NSURLConnection alloc] initWithRequest:imageRequest 
                                            delegate:self];

在 Rails 服务器上，db/migrate 中的照片迁移如下所示:

class CreatePhotos < ActiveRecord::Migration
  def self.up
    create_table :photos do |t|

      t.column :user_id, :integer
      t.column :title, :string
      t.column :body, :text
      t.column :created_at, :datetime

#  the following are for attachment_fu

      t.column :photo, :binary
      t.column :content_type, :string
      t.column :filename, :string
      t.column :size, :integer
      t.column :parent_id, :integer
      t.column :thumbnail, :string
      t.column :width, :integer
      t.column :height, :integer


    end
  end

  def self.down
    drop_table :photos
  end
end

在 Rails 服务器上，我有一个照片模型 app/models/photo.rb ，其中包含以下代码:

class Photo < ActiveRecord::Base

    has_attachment :storage       => :file_system,
                   :resize_to     => '640x480',
                   :thumbnails    => { :thumb => '160x120', :tiny => '50>' },
                   :max_size      => 5.megabytes,
                   :content_type  => :image,
                   :processor     => 'Rmagick'
    validates_as_attachment
    belongs_to :user
end

Rails Controller 有以下代码:

def iphone_photo_to_website
    @udid          = params[:id]
    @userfile      = params[:userfile]

  @photo_params = { :user_id               => @user.id,
                    :photo                 => @userfile,
                    :content_type          => 'image',
                    :filename              => @userfile.original_path,
                    :uploaded_data         => @userfile
                  }
 image = Photo.new(@photo_params)
 image.save


end

当“image.save”执行时，它返回“false”。有谁知道我如何找到导致 image.save 返回 false 的错误？或者有谁知道如何将照片正确保存在数据库中？

Answer 1

我终于能够使用以下代码将图像保存到数据库:

  @userfile      = params[:userfile]

  image = Photo.new(:uploaded_data => params[:userfile])

  image.user_id          = @user.id
  image.photo            = @userfile
  image.width            = 105
  image.height           = 104
  basename               = File.basename(image.filename).gsub(/[^\w._-]/, '')
  image.content_type     = "image/" + basename.split("\.")[1]

  image.save

当使用 uploaded_data 字段将图像创建为 Photo.new 时，image.filename 就会被设置。

我还必须从 iPhone 上的 Objective-C 代码中删除以下行才能正常工作。

 [body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];