Fix Spree::LogEntry::DisallowedClass error for failed responses

[gsmendoza]

Summary

A error Braintree response would raise the following error:

Spree::LogEntry::DisallowedClass:
  Tried to dump unspecified class: Symbol

  You can specify custom classes to be loaded in config/initializers/spree.rb. E.g:

  Spree.config do |config|
    config.log_entry_permitted_classes = ['MyClass']
  end
# ./app/controllers/checkouts_controller.rb:54:in `transition_forward'
# ./app/controllers/checkouts_controller.rb:21:in `update'
# ./app/controllers/store_controller.rb:26:in `block in lock_order'
# ./app/controllers/store_controller.rb:26:in `lock_order'

Solidus Version:

3.4.0.dev

Cause

When SolidusBraintree::Response.build(result) accepts an error result, the result.params it passes to the new response has symbol keys. Here's a sample of the result.params:

    {:transaction=>
      {:amount=>"20.00",
       :order_id=>"R300000001",
       :channel=>"Solidus",
       :options=>{:store_in_vault_on_success=>"true"},
       :payment_method_token=>"0ev7m4dt",
       :customer_id=>"180763858",
       :type=>"sale"}}

Solution

Deep-stringify the result params.

Demonstration

See https://github.com/solidusio/solidus_braintree/tree/gsmendoza/110-log-entry-disallowed-class-demo for a demonstration of the error and the my attempts to fix it. Start from the "Try enabling venmo specs" commit.

Additional context

Related to #108.

There is also a PR in Solidus that will temporarily allow bad payloads to be saved in payment log entries. See solidusio/solidus#4953