Wrongly formated ids when using mongoid head

[sphw]

I am upgrade my application to rails 4 and I have noticed that the id field is being formatted wrong. it is being formated like this
"_id": {
"$oid": "51c7bd98e77989d1f1000002"
}
I believe this stems from mongoid returning a json object now instead of simple a string .

[brentkirby]

I literally just finished dealing with this so thought I'd respond :) This is actually a Mongoid / Moped thing and intentional, to match what Mongo does natively.

You'll need to handle this yourself for the time being ( not sure if they are going to do anything different or not ). What I did was to just override .to_json and .as_json on Moped::BSON::ObjectId in a Rails initializer.

module Moped
  module BSON
    class ObjectId
      alias :to_json :to_s
      alias :as_json :to_s
    end
  end
end

This was also the suggestion offered by Durran. You can find more info here

[mrrooijen]

@brentkirby 👍 now I can clean up my code again.

[lukaszx0]

If I understand correctly that's not AMS issue and this can be closed.

[spastorino]

/cc @arthurnn

[arthurnn]

@brentkirby is right. On mongoid the default JSON output for Object id is: {"$oid": "...."} so if you wanna change that behaviour you would have to monkey patch the ObjectId class, something like this:
Mongoid 3.x:

module Moped
  module BSON
    class ObjectId
      alias :to_json :to_s
      alias :as_json :to_s
    end
  end
end

Mongoid 4:

module BSON
  class ObjectId
    alias :to_json :to_s
    alias :as_json :to_s
  end
end

That should be enough to solve this issue.
Thanks for the ticket anyways.

[mateusdelbianco]

@arthurnn as_json and to_json can accept arguments. The code below worked better for me.

module BSON
  class ObjectId
    def as_json(*args)
      to_s
    end

    alias :to_json :as_json
  end
end

[barodeur]

@mateusdelbianco thx, just had a little issue with your code, it produced a JSON like this for me which was invalid :

{
  "id":5123bf6c104729020000004f
  ...
}

I had to add a to_json call to the string.

module BSON
  class ObjectId
    def as_json(*args)
      to_s.to_json
    end

    alias :to_json :as_json
  end
end

[jstejada]

@mateusdelbianco @barodeur this is really helpful, thanks! Also, you can actually just override #as_json without the aliases:

module BSON
  class ObjectId

    def as_json(*args)
      to_s
    end

  end
end

This will produce proper json output since #to_json jsonifyies whatever #as_json returns, so it will add the proper quotes to the string, and #as_json will return just a regular string as intended.

[dangalg]

What if I want the exact opposite?

from:
"_id": "51c7bd98e77989d1f1000002"

to:
"_id": {
"$oid": "51c7bd98e77989d1f1000002"
}

[dfabreguette]

Just had an issue using elasticsearch mongoid gem (calling rake es:reindex). After Some Search I found this github issue solving my problem : nesquena/backburner#80

[jagdeepsingh]

Configuration

# Gemfile
gem 'rails', '~> 5.2.0'
gem 'mongoid', '~> 7.0.1'
gem 'bson_ext', '~> 1.5.1'
gem 'active_model_serializers', '~> 0.10.7'

mongoid document serialized using ActiveModel::Serializer

Default

Output

{
    "id": {
        "$oid": "5b336e9d6120b24c62287e5b"
    },
    "token": "823725b2eeb8ced8bed3c58fe18479d1d07d616c072dc02a0e",
    "refresh_token": null,
    "expires_in": 900,
    "revoked_at": null,
    "resource_owner_id": {
        "$oid": "59c8a5bd6120000c4e000164"
    }
}

With initializer

# config/initializers/bson.rb
module BSON
  class ObjectId
    alias :as_json :to_s
  end
end

Output

{
    "id": "5b336e9d6120b24c62287e5b",
    "token": "823725b2eeb8ced8bed3c58fe18479d1d07d616c072dc02a0e",
    "refresh_token": null,
    "expires_in": 900,
    "revoked_at": null,
    "resource_owner_id": "59c8a5bd6120000c4e000164"
}

[rrecio]

The solution @jstejada posted worked better for me:

module BSON
  class ObjectId

    def as_json(*args)
      to_s
    end

  end
end

The other solutions crashed due to lack of *args or generated id strings containing special quote character at the begining and end of string, which led my REST consumer code to read id field as "\"123131b23b1b23b1b3\"" instead of the expected "123131b23b1b23b1b3"