[MaybeBug/MaybeDoc] How to model complex dependencies

[nulltoken]

:wave: @linkdotnet

I either might need some (very welcome) guidance or there's some kind of a dark corner in NCronJob.

This graph sold me on NCronJob.

However, I can't seem to find how to properly register the Jobs to make this work. And I haven't found a test showing any dependency more than one level deep.

The doc states that RunJob can be chained to allow multiple jobs to run after the completion of the main job.. Which would allow some

A  ---  success  ---  B
                  |_  C

My understanding is that ExecuteWhen can be chained as well to model

A  ---  success  ---  B
    |_  success  ---  C

Would it be possible to add a unit test showing how to properly register this kind of dependency chain?

A  ---  success  ---  B --- success --- C

[nulltoken]

FWIW I've tried the following...

        *.AddNCronJob(n => n.AddJob<B>()
            .ExecuteWhen(success: s => s.RunJob<C>()));

        *.AddNCronJob(n => n.AddJob<A>()
            .ExecuteWhen(success: s => s.RunJob<A>()));

... but it seems that there's no recursive analysis of the dependencies of B when building the JobDefiniton of A (or I haven't been able to find it :-/)

[linkdotnet]

Hey @nulltoken

You might be on to something. So the A --- success --- B --- success --- C should be modelled like this:

using NCronJob;

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddNCronJob(
    o => o.AddJob<JobA>()
        .ExecuteWhen(s => s.RunJob<JobB>())
        .AddJob<JobB>()
        .ExecuteWhen(s => s.RunJob<JobC>()));

var app = builder.Build();

app.MapGet("/", (IInstantJobRegistry registry) =>
{
    registry.RunInstantJob<JobA>();
});

app.Run();

class JobA : IJob
{
    public Task RunAsync(IJobExecutionContext context, CancellationToken token)
    {
        Console.WriteLine("JobA");
        return Task.CompletedTask;
    }
}

class JobB : IJob
{
    public Task RunAsync(IJobExecutionContext context, CancellationToken token)
    {
        Console.WriteLine("JobB");
        return Task.CompletedTask;
    }
}

class JobC : IJob
{
    public Task RunAsync(IJobExecutionContext context, CancellationToken token)
    {
        Console.WriteLine("JobC");
        return Task.CompletedTask;
    }
}

But that doesn't work as expected.

A  ---  success  ---  B
    |_  success  ---  C

Exactly this should be similar possible. I will check those cases. Thanks!

[linkdotnet]

Okay I found a few issues! Will push a fix soon with updated documentation

[linkdotnet]

So both bugs are fixed, I did add some test and updated the documentation. Will put the links here once everything is published

[linkdotnet]

Latest package: https://www.nuget.org/packages/NCronJob/3.2.0 Here is the updated chapter: https://docs.ncronjob.dev/features/model-dependencies/#run-mutliple-jobs-after-the-completion-of-a-job

Thanks again for bringing up the issues @nulltoken ! Much appreciated

[nulltoken]

You might be on to something.

@linkdotnet Duh. My attempts were actually relying on calling the builder twice, not AddNCronJob... Sorry for the misleading (too hastily typed) pear-shaped repro :-/

So both bugs are fixed, I did add some test and updated the documentation. Will put the links here once everything is published

...but you got the gist of it and eventually, once again, saved the world. Thanks for that! I've tested it and it now works as expected.

One thing the doco may benefit from would maybe to also register JobC (in order to avoid the warning in the logs).

[linkdotnet]

Good point! Will update the docs