Quartz.Net Create Job Plugin Architecture

Question

I am working on a Quartz.Net web API. I am currently trying to crate a plugin architecture for loading IJob as plugins.

Currently, I can load the assemblies from a plugins directory.

        private void LoadPlugins(ISchedulerFactory factory)
        {
            var scheduler = factory.GetScheduler().Result;
            string folder = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + @"\Plugins";
            if (Directory.Exists(folder))
            {
                string[] files = Directory.GetFiles(folder, "*.dll");

                foreach (string file in files)
                {
                    Assembly plugin = AppDomain.CurrentDomain.Load(File.ReadAllBytes(file));

                    foreach (var t in plugin.GetTypes())
                    {
                        if (t.GetInterfaces().Any(i => i == typeof(IJob)))
                        {
                            scheduler.AddJob(JobBuilder.Create(t).WithIdentity(t.Name + " Job").StoreDurably().Build(), true).Wait();
                        }
                    }

                }
            }
        }

The Quartz.Net scheduler does add the job.

If I call the Quartz.Net scheduler.CheckExists(AJobKeyFromThePlugin) Then it does return true.

However, at a latter point in the application If I try to get the ```JobDetail`` from the scheduler I get the following exception.

Couldn't retrieve job because a required type was not found: Could not load type...

I have tried to keep a list of the loaded plugin assemblies in a statically loaded list, but that doesn't seem to help.

How can I better load the assemblies so that Quartz.Net can see them?

Answer 1

You need to implement the ITypeLoadHelper and configure Quartz.net to use your TypeLoadHelper.

The Quartz.Net property

"quartz.scheduler.typeLoadHelper.type"