Dont call as_json on Delayed::Backend::Sequel::Job

[davidbegin]

instead call #to_hash, and turn all the keys to strings, to
keep the rest of the implementation untouched

[davidbegin]

We are seeing an error in Rollbar, when using Sequel and Delayed Job.
'undefined method `as_json'' for #Delayed::Backend::Sequel::Job:0x007fe7f57d31f8

In this file: https://github.com/rollbar/rollbar-gem/blob/master/lib/rollbar/plugins/delayed_job/job_data.rb#L9

we are calling on @as_json on this class in Delayed Job Sequel
https://github.com/TalentBox/delayed_job_sequel/blob/56e7d69e1710b75ae7044a884961e1ebfd6a4661/lib/delayed/backend/sequel.rb

I updated Rollbar to just use #to_hash, if #as_json is not defined.

[jondeandres]

Hey @davidbegin, thanks for this. Let me test it and we'll merge it.

[jondeandres]

I think we should extract this code into its own method. And also, we should ensure that job responds to #to_hash.

[davidbegin]

Thanks for reviewing this, I will work on those changes right now.

[davidbegin]

As I started to add specs to cover if the job object didn't respond to #as_json or #to_hash I noticed various problems.

Here are my debugging notes:

---

First I noticed that the spec file for JobData is not being run, because it doesn't end with _spec.

spec/rollbar/plugins/delayed_job/job_data.rb

Once I update to job_data_spec, and run the specs, I get:

cannot load such file -- rollbar/delayed_job (LoadError)

I am not sure what is trying to be loaded, as there is no rollbar/delayed_job file.
So for my next debugging step, I just commented out this require to see what would happen.

this triggers:

spec/rollbar/plugins/delayed_job/job_data_spec.rb:12:in `<top (required)>': uninitialized constant Rollbar::Delayed (NameError)'`

then I noticed that the spec is testing the class

describe Rollbar::Delayed::JobData do

but if we open up:

lib/rollbar/plugins/delayed_job/job_data.rb

We see it's only declared as

class JobData

and not in the Rollbar::Delayed namespace.

When I search to see where JobData is used, I see its only used in

lib/rollbar/plugins/delayed_job/plugin.rb

And it is indeed called within the Rollbar::Delayed namespace, so I assume this was a mistake.

So next I place JobData in this namespace

When I run the specs I still get the error:

spec/rollbar/plugins/delayed_job/job_data_spec.rb:12:in `<top (required)>': uninitialized constant Rollbar::Delayed (NameError)'`

So I require the JobData class explicitly:

require 'rollbar/plugins/delayed_job/job_data'

And the spec finally runs!
...except it fails with:

expected `{"attempts"=>1, "priority"=>0, "handler"=>{}}.eql?({"priority"=>0, "attempts"=>1, "handler"=>{"foo"=>"bar"}})` to return true, got false

I had a feeling that it was raising an error, and being caught in the handler_object method,
so when I outputed the error I see:

uninitialized constant Delayed::Backend::Base::DeserializationError

I assumed this was because I commented out the require "rollbar/delayed_job"

So I instead added require "delayed_job"

Now the spec knows about Delayed::Backend::Base::DeserializationError, but a new error is raised:

undefined method `object' for {"foo"=>"bar"}:Hash`

Which is from the first line in the handler_object method:

object = job.payload_object.object

job.payload_object returns a hash, which doesn't respond to object
job in this case is a Delayed::Backend::Test::Job

So far this is where I have got, but since I going down a rabbit-hole, I thought it might be good to share my findings and get some help.

Thanks!

[jondeandres]

Hey @davidbegin,

thank you very much for the notes. You've found a missing piece we forgot to move when we added the plugins architecture. So, JobData should be in the correct namespace and the require in the job_data spec should be fixed.

We'll do this change ourself and check that the specs are passing in master. After that, I think it's a good starting for your PR.

[michaelirey]

@jondeandres Has there been any movement on this PR? Is there anything I could do to help?

Thanks!