msbuildtask.md

MessagePack Compiler via MSBuild Task

Cold startup performance and AOT environments can benefit by pre-compiling the specialized code for serializing and deserializing your custom types.

Install the MessagePack.MSBuild.Tasks NuGet package in your project:

This package automatically gets the MessagePack Compiler (mpc) to run during the build to produce a source file in the intermediate directory and adds it to the compilation, consumable in the normal way:

using System;
using MessagePack;
using MessagePack.Resolvers;

class Program
{
    static void Main(string[] args)
    {
        var o = new SomeObject { SomeMember = "hi" };

        var options = MessagePackSerializerOptions.Standard.WithResolver(
            CompositeResolver.Create(
                GeneratedResolver.Instance,
                StandardResolver.Instance
            ));
        byte[] b = MessagePackSerializer.Serialize(o, options);
        var o2 = MessagePackSerializer.Deserialize<SomeObject>(b, options);
        Console.WriteLine(o2.SomeMember);
    }
}

[MessagePackObject]
public class SomeObject
{
    [Key(0)]
    public string SomeMember { get; set; }
}

Customizations

A few MSBuild properties can be set in your project to customize mpc:

Property	Purpose	Default value
MessagePackGeneratedResolverNamespace	The prefix for the namespace under which code will be generated. .Formatters is always appended to this value.	MessagePack
MessagePackGeneratedResolverName	The name of the generated type.	GeneratedResolver
MessagePackGeneratedUsesMapMode	A boolean value that indicates whether all formatters should use property maps instead of more compact arrays.	false

For example you could add this xml to your project file to set each of the above properties (in this example, to their default values):

<PropertyGroup>
 <MessagePackGeneratedResolverNamespace>MessagePack</MessagePackGeneratedResolverNamespace>
 <MessagePackGeneratedResolverName>GeneratedResolver</MessagePackGeneratedResolverName>
 <MessagePackGeneratedUsesMapMode>false</MessagePackGeneratedUsesMapMode>
</PropertyGroup>