如何从Ruby中的BSON文档中获取哈希值？

Question

I save a hash into MongoDB using the Mongo gem. I then get a BSON::Document back when I query the database in Ruby.

How do I convert the BSON::Document back to the original hash?

doc = { name: 'Steve', hobbies: [ 'hiking', 'tennis', 'fly fishing' ] }

result = collection.insert_one(doc)

steve = collection.find( { name: 'Steve' } ).first

returns:

{"_id"=>BSON::ObjectId('5baf68cd65992f3734f396ab'), "name"=>"Steve", "hobbies"=>["hiking", "tennis", "fly fishing"]}

Answer 1

As per the details mentioned in the post it seems like you want to convert BSON db object to json(Hash) object.

BSON contains JSON module which provides the below mentioned method to convert object to json

to_json

https://www.rubydoc.info/github/mongodb/bson-ruby/BSON/JSON

Not sure of the below mentioned method, as I have only used it in ActiveRecord object, try if it works

result.as_json(only: ["name_of_the_column_you_want"])