Server error, please check backend logs for details

[casiodk]

I suddenly started getting this error in production - but only on the index page, if I go on a specific stream it works as intended.

When I go to the specific event that is breaking the screen looks like this

And the event look like this

=> #<Etfs::SIX::EtfBidUpdated:0x00007f48a03917d8
 @data={:etf_id=>1, :bid=>117.595, :previous_bid=>0.0, :bid_change_percentage=>Infinity},
 @event_id="xxx",
 @metadata=
  #<RubyEventStore::Metadata:0x00007f48a03917b0
   @h=
    {:locale=>"da",
     :event_version=>1,
     :correlation_id=>"xxx",
     :timestamp=>2024-11-08 22:00:48.014565 +0100,
     :valid_at=>2024-11-08 22:00:48.014565 +0100}>>

So I am guessing that the Infinity value in the data is breaking things?

[lukaszreszke]

Hi @casiodk. Thanks for reporting. We'll take a look at this

[mostlyobvious]

What's the Infinity that you're using here? It is not a Float::INIFINITY for sure.

irb(main):009:0> JSON.dump(Float::INFINITY)
=> "Infinity"

The problem lies within serializing event data to JSON for the Browser. If that's a custom type/ValueObject used in data, JSON won't be able to process it without additional mapping.

[casiodk]

I am using the YAML serializer, so it should be able to deserialize right?

Rails.configuration.to_prepare do
  Rails.configuration.key_repository = EncryptionKeyRepository.new
  Rails.configuration.event_store = RailsEventStore::Client.new(
    mapper: RubyEventStore::Mappers::EncryptionMapper.new(Rails.configuration.key_repository, serializer: RubyEventStore::Serializers::YAML),
    repository: RailsEventStoreActiveRecord::EventRepository.new(serializer: RubyEventStore::Serializers::YAML),
    dispatcher: RubyEventStore::ComposedDispatcher.new(
      RailsEventStore::AfterCommitAsyncDispatcher.new(scheduler: RailsEventStore::ActiveJobScheduler.new(serializer: RubyEventStore::Serializers::YAML)),
      RubyEventStore::Dispatcher.new
    ),
    request_metadata: lambda do |env|
      request = ActionDispatch::Request.new(env)

      {
        request_uuid: request.uuid
      }
    end
  )

  EventSubscribers::Base.call
end

[casiodk]

I am also able to deserialize in the console without any problems

PRODUCTION [2] pry(main)> event = EventStore.find_event("b3fcc70a-7148-417a-9600-a4ab890c6a0b")
D, [2024-11-14T09:50:53.683378 #27432] DEBUG -- :   RubyEventStore::ActiveRecord::Event Load (0.7ms)  SELECT "event_store_events".* FROM "event_store_events" WHERE "event_store_events"."event_id" = $1 ORDER BY "event_store_events"."id" ASC LIMIT $2  [["event_id", "b3fcc70a-7148-417a-9600-a4ab890c6a0b"], ["LIMIT", 1]]
=> #<Etfs::SIX::EtfBidUpdated:0x00007fb4c115fc98
 @data={:etf_id=>1, :bid=>120.595, :previous_bid=>0.0, :bid_change_percentage=>Infinity},
 @event_id="b3fcc70a-7148-417a-9600-a4ab890c6a0b",
 @metadata=
  #<RubyEventStore::Metadata:0x00007fb4c115fb58
   @h={:locale=>"da", :event_version=>1, :correlation_id=>"4abe1ad7-5b83-4feb-a743-d6b044e114d2", :timestamp=>2024-11-08 22:00:48.014565 +0100, :valid_at=>2024-11-08 22:00:48.014565 +0100}>>
PRODUCTION [3] pry(main)> event.data[:bid_change_percentage]
=> Infinity
PRODUCTION [4] pry(main)> event.data[:bid_change_percentage].class
=> Float

[fidel]

Hello @casiodk, I had some time yesterday to investigate this scenario. While JSON.dump(1.0/0) dumps Float::INFINITY to "Infinity" string, it doesn't happen when it's a value in a hash:

irb(main):003> JSON.dump(1.0/0)
=> "Infinity"
irb(main):004> JSON.dump({ infinity: 1.0/0 })
=> "{\"infinity\":Infinity}"

In general, this behavior doesn't follow ECMA-404 nor RFC 8259 as

Numeric values that cannot be represented as sequences of digits (such as Infinity and NaN) are not permitted.

Infinity is obviously not an "Infinity" and JSON parser in our browser's frontend can't handle this as it not a correct JSON value. Fun fact, some tools actually parse that, but there's no standarized behavior

echo "{\"infinity\":Infinity}" | jq
{
  "infinity": 1.7976931348623157e+308
}

It also differs on which method from Ruby's JSON module you'll use:

irb(main):003> JSON.parse('[Infinity]')
/Users/fidel/.gem/ruby/3.3.6/gems/json-2.8.1/lib/json/common.rb:204:in `parse': unexpected token at 'Infinity]' (JSON::ParserError)
    from /Users/fidel/.gem/ruby/3.3.6/gems/json-2.8.1/lib/json/common.rb:204:in `parse'
    from (irb):3:in `<main>'
    from <internal:kernel>:187:in `loop'
    from /Users/fidel/.gem/ruby/3.3.6/gems/irb-1.14.1/exe/irb:9:in `<top (required)>'
    from /Users/fidel/.gem/ruby/3.3.6/bin/irb:25:in `load'
    from /Users/fidel/.gem/ruby/3.3.6/bin/irb:25:in `<main>'
irb(main):004> JSON.load('[Infinity]')
=> [Infinity]
irb(main):005> JSON.parse('[Infinity]', allow_nan: true)
=> [Infinity]

We'll try to fix this issue on our end.

[fidel]

@casiodk issue has been resolved in https://github.com/RailsEventStore/rails_event_store/commit/a2885d4f2ea630f635b33b1f87bf30491c39857b, not sure when we'll make a release, so you can stick to this particular ref in your Gemfile.

[casiodk]

Awesome, thanks a lot guys!!

[fidel]

You're welcome, at least we've learned something new 😉

[casiodk]

I tried to reference, but now I am getting this error and a blank page

Uncaught ReferenceError: Elm is not defined at bootstrap.js:5:13

[casiodk]

gem "rails_event_store", git: "https://github.com/RailsEventStore/rails_event_store", ref: "a2885d4f2ea630f635b33b1f87bf30491c39857b"

[fidel]

Yes, sorry, I forgot that we don't build js for every ref. This one https://github.com/RailsEventStore/rails_event_store/commit/8f108b278a7f5a9a17b7a63655bdfce9c976d82b will work

[casiodk]

Awesome! it works :)