Saving a nested hash in Ruby on Rails

Question

I'm trying to save a nested Hash to my database and retrieve it, but nested values are lost upon retrieval.

My model looks like this:

class User
  serialize :metadata, MetaData
end

The class MetaData looks like this:

class MetaData < Hash
  attr_accessor :availability, :validated
end

The code I'm using to store data looks something like this (the real data is coming from a HTML form, though):

user = User.find(id)
user.metadata.validated = true
user.metadata.availability = {'Sunday' => 'Yes', 'Monday' => 'No', 'Tuesday' => 'Yes'}
user.save

When I look at the data in the database, I see the following:

--- !map:MetaData 
availability: !map:ActiveSupport::HashWithIndifferentAccess 
  Sunday: "Yes"
  Monday: "No"
  Tuesday: "Yes"
validated: true

The problem occurs when I try to get the object again:

user = User.find(id)
user.metadata.validated # <- this is true
user.metadata.availability # <- this is nil

Any ideas? I'm using Rails 3.1 with Postgresql as my datastore.

junky · Accepted Answer · 2012-02-28 23:40:12Z

1

If you look in the database you see "map:ActiveSupport::HashWithIndifferentAccess" for availability?

My approach would be to separate out the single instance of availablity from the hash collection structure of days available.

answered Feb 28, 2012 at 23:40

junky

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2 Comments

It's coming from an HTML form as a HashWithIndifferentAccess. Are you suggesting to convert it from this to a regular Hash? and store that instead?

I tried converting it to a regular Hash and am still having the same problem.

Andrew Cetinic · Accepted Answer · 2012-02-28 23:43:41Z

0

you mean user.metadata.validated # <- this is true ?

What DB columns are metadata and availability stored as? They need to be TEXT

answered Feb 28, 2012 at 23:43

Andrew Cetinic

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There is only 1 column, called metadata. It is of type text. Availability is a key on the hash that I'm storing in metadata.