Serialization (System.Text.Json)

Tips

JSON is recommended persistent format to store data in database for greenfield projects. You should also strongly consider setting useProperties to true to restrict key-values to be strings.

Quartz.Serialization.SystemTextJson provides JSON serialization support for job stores using System.Text.Json facilities to handle the actual serialization process.

Installation

You need to add NuGet package reference to your project which uses Quartz.

    Install-Package Quartz.Serialization.SystemTextJson

Configuring

Classic property-based configuration

var properties = new NameValueCollection
{
 ["quartz.jobStore.type"] = "Quartz.Impl.AdoJobStore.JobStoreTX, Quartz",
 ["quartz.serializer.type"] = "stj"
};
ISchedulerFactory schedulerFactory = new StdSchedulerFactory(properties);

Configuring using scheduler builder

var config = SchedulerBuilder.Create();
config.UsePersistentStore(store =>
{
    // it's generally recommended to stick with
    // string property keys and values when serializing
    store.UseProperties = true;
    store.UseGenericDatabase(dbProvider, db =>
        db.ConnectionString = "my connection string"
    );

    store.UseSystemTextJsonSerializer();
});
ISchedulerFactory schedulerFactory = config.Build();

Migrating from binary serialization

There's now official solution for migration as there can be quirks in every setup, but there's a recipe that can work for you.

Configure custom serializer like MigratorSerializer below that can read binary serialization format and writes JSON format
Either let system gradually migrate as it's running or create a program which loads and writes back to DB all relevant serialized assets

Example hybrid serializer

using System.Text.Json;

using Quartz.Simpl;
using Quartz.Spi;

namespace Quartz;

public sealed class MigratorSerializer : IObjectSerializer
{
    private readonly BinaryObjectSerializer binarySerializer;
    private readonly SystemTextJsonObjectSerializer jsonSerializer;

    public MigratorSerializer()
    {
        binarySerializer = new BinaryObjectSerializer();
        // you might need custom configuration, see sections about customizing
        // in documentation
        jsonSerializer = new SystemTextJsonObjectSerializer();
    }

    public T DeSerialize<T>(byte[] data) where T : class
    {
        try
        {
            // Attempt to deserialize data as JSON
            return jsonSerializer.DeSerialize<T>(data)!;
        }
        catch (JsonException)
        {
            // Presumably, the data was not JSON, we instead use the binary serializer
            var binaryData = binarySerializer.DeSerialize<T>(data);
            if (binaryData is JobDataMap jobDataMap)
            {
                // make sure we mark the map as dirty so it will be serialized as JSON next time
                jobDataMap[SchedulerConstants.ForceJobDataMapDirty] = "true";
            }
            return binaryData!;
        }
    }

    public void Initialize()
    {
        binarySerializer.Initialize();
        jsonSerializer.Initialize();
    }

    public byte[] Serialize<T>(T obj) where T : class
    {
        return jsonSerializer.Serialize(obj);
    }
}

Customizing serialization options

If you need to customize serialization, you need to inherit custom implementation and override CreateSerializerOptions.

class CustomJsonSerializer : SystemTextJsonObjectSerializer
{
   protected override JsonSerializerOptions CreateSerializerOptions()
   {
       var options = base.CreateSerializerOptions();
       options.Converters.Add(new MyCustomConverter());
       return options;
   }
}

And then configure it to use

store.UseSerializer<CustomJsonSerializer>();
// or
"quartz.serializer.type" = "MyProject.CustomJsonSerializer, MyProject"

Customizing calendar serialization

If you have implemented a custom calendar, you need to implement a ICalendarSerializer for it. There's a convenience base class CalendarSerializer that you can use the get strongly-typed experience.

Custom calendar and serializer

using System;
using System.Runtime.Serialization;
using System.Text.Json;

using Quartz.Impl.Calendar;
using Quartz.Serialization.SystemTextJson;

[Serializable]
public sealed class CustomCalendar : BaseCalendar
{
    public CustomCalendar()
    {
    }

    // binary serialization support
    private CustomCalendar(SerializationInfo info, StreamingContext context) : base(info, context)
    {
        SomeCustomProperty = info?.GetBoolean("SomeCustomProperty") ?? true;
    }

    public bool SomeCustomProperty { get; set; } = true;

    // binary serialization support
    public override void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        base.GetObjectData(info, context);
        info?.AddValue("SomeCustomProperty", SomeCustomProperty);
    }
}

// JSON serialization support
public sealed class CustomCalendarSerializer : CalendarSerializer<CustomCalendar>
{
    protected override CustomCalendar Create(JsonElement jsonElement, JsonSerializerOptions options)
    {
        return new CustomCalendar();
    }

    protected override void SerializeFields(Utf8JsonWriter writer, CustomCalendar calendar, JsonSerializerOptions options)
    {
        writer.WriteBoolean("SomeCustomProperty", calendar.SomeCustomProperty);
    }

    protected override void DeserializeFields(CustomCalendar calendar, JsonElement jsonElement, JsonSerializerOptions options)
    {
        calendar.SomeCustomProperty = jsonElement.GetProperty("CustomProperty").GetBoolean();
    }

    public override string CalendarTypeName => "CustomCalendar";
}

Configuring custom calendar serializer

var config = SchedulerBuilder.Create();
config.UsePersistentStore(store =>
{
    store.UseSystemTextJsonSerializer(json =>
    {
        json.AddCalendarSerializer<CustomCalendar>(new CustomCalendarSerializer());
    });
});

// or just globally which is what above code calls
SystemTextJsonObjectSerializer.AddCalendarSerializer<CustomCalendar>(new CustomCalendarSerializer());