YamlDotNet !!二进制类型

Question

我正在尝试使用 yaml 发送二进制数据，即字节数组。根据 yaml 文档 Yaml Binary Type，这是受支持的。在 Java 方面，我使用 SnakeYaml，如果传递了 byte[] 的值，那么 yaml 会正确给出 !!binary.

YamlDotNet 似乎不支持此功能 "out of the box"。下面的代码片段创建了一个整数值序列：

IDictionary<string, object> data = new Dictionary<string, object>();

        const string value = ":| value: <XML> /n\n C:\cat";
        byte[] bytes = Encoding.UTF8.GetBytes(value);
        data.Add(ValueKey, bytes);


        // Turn the object representation into text
        using (var output = new StringWriter())
        {
            var serializer = new Serializer();
            serializer.Serialize(output, data);

            return output.ToString();
        }

输出如下：

val:\r- 58\r- 124\r- 32\r- 118\r- 97\r- 108\r- 117\r- 101\r- 58\r- 32\r- 60\r- 88\r- 77\r- 76\r- 62\r- 32\r- 47\r- 110\r- 10\r- 32\r- 67\r- 58\r- 92\r- 99\r- 97\r- 116\r

但我想要更像的东西：

  val: !!binary |-
OnwgdmFsdWU6IDxYTUw+IC9uCiBDOlxjYXQ=

谁能推荐解决方法？

Answer 1

对于任何感兴趣的人....我通过自己创建字符串并添加 !!binary 标记并进行一些清理来解决此问题。下面是代码。

ToYaml:

IDictionary<string, string> data = new Dictionary<string, string>();
string byteAsBase64Fromat = Convert.ToBase64String("The string to convert");
byteAsBase64Fromat = "!!binary |-\n" + byteAsBase64Fromat + "\n";

data.Add(ValueKey, byteAsBase64Fromat);
string yaml;
using (var output = new StringWriter())
{
  var serializer = new Serializer();
  serializer.Serialize(output, data);

   yaml = output.ToString();
}
string yaml = yaml.Replace(">", "");
return yaml.Replace(Environment.NewLine + Environment.NewLine,     Environment.NewLine);

然后返回：

string binaryText = ((YamlScalarNode)data.Children[new YamlScalarNode(ValueKey)]).Value
String value = Convert.FromBase64String(binaryText);

Answer 2

添加对自定义类型支持的首选方法是使用自定义 IYamlTypeConverter。 !!binary 类型的可能实现是：

public class ByteArrayConverter : IYamlTypeConverter
{
    public bool Accepts(Type type)
    {
        // Return true to indicate that this converter is able to handle the byte[] type
        return type == typeof(byte[]);
    }

    public object ReadYaml(IParser parser, Type type)
    {
        var scalar = (YamlDotNet.Core.Events.Scalar)parser.Current;
        var bytes = Convert.FromBase64String(scalar.Value);
        parser.MoveNext();
        return bytes;
    }

    public void WriteYaml(IEmitter emitter, object value, Type type)
    {
        var bytes = (byte[])value;
        emitter.Emit(new YamlDotNet.Core.Events.Scalar(
            null,
            "tag:yaml.org,2002:binary",
            Convert.ToBase64String(bytes),
            ScalarStyle.Plain,
            false,
            false
        ));
    }
}

要在 Serializer 中使用转换器，您只需使用以下代码注册它：

var serializer = new Serializer();
serializer.RegisterTypeConverter(new ByteArrayConverter());

对于Deserializer，还需要注册转换器，但是还需要添加标签映射，将!!binary标签解析为byte[]类型：

var deserializer = new Deserializer();
deserializer.RegisterTagMapping("tag:yaml.org,2002:binary", typeof(byte[]));
deserializer.RegisterTypeConverter(new ByteArrayConverter());

A fully working example can be tried here

YamlDotNet !!二进制类型

YamlDotNet !!binary type

yamldotnet