Introduction

This is a character encoding-aware JSON middleware for Faraday.

The default JSON middleware from lostisland/faraday_middleware is not character encoding aware. This is problematic because by default, Ruby performs I/O based on locale settings. If your locale specifies one character encoding, but the request or response body is encoded in another, you will end up with a Ruby string that pretends to be one encoding, but cannot correctly be interpreted as such.

Worse, Ruby 1.8 and later Ruby versions will not behave consistently, as 1.8 does not yet understand character encodings internally. There is a lengthy discussion about this at https://bugs.ruby-lang.org/issues/2567

Still worse, JSON used to specify UTF-8 encoding as mandatory, but now loosened this to any Unicode character set. The result is that some JSON libraries still only understand UTF-8.

This middleware fixes these issues rather brute-force by:

• Accepting the Content-Type charset value as the correct encoding, and converting the body from Faraday adapters to this encoding.
• Only sending UTF-8 encoded JSON, converting raw data if necessary.
• Always setting the UTF-8 charset when sending this UTF-8 encoded JSON.

When no charset is provided, all bets are off. The correct default would be to assume US-ASCII, but that may break some code. This middleware lets you override this default.

Add this line to your application's Gemfile:

gem 'faraday_json'

And then execute:

$ bundle

Or install it yourself as:

$ gem install faraday_json

require 'faraday'
require 'faraday_middleware'  # optional
require 'faraday_json'        # replaces JSON handling from previous require

client = Faraday.new('http://some_url') do |conn|
  conn.request :json
  conn.response :json

  conn.adapter Faraday.default_adapter
end

client.post '/', :a => "röck döts"

1. faraday_middleware is not required for JSON handling.
2. Require faraday_json after faraday_middleware to override the behaviour from faraday_middleware.