Handle Faraday::Error::ConnectionFailed with middleware

Faraday is a really nice, middleware-based HTTP client for Ruby. For simple libraries, I recommend HTTParty, but Faraday is a really awesome solution when you need full control over the complete stack.

However, Faraday has one feature/flaw that I have found. If Faraday is unable to connect to a server, it throws a really nasty error. I whipped up a tiny middleware to handle this error:

class Middleware::Exceptions < Faraday::Middleware
  def call(env)
    begin
      @app.call(env)
    rescue Faraday::Error::ConnectionFailed => e
      # Do whatever to handle your error here, maybe raise a more semantic error
    end
  end
end

And then tell Faraday to use this middleware:

Faraday.new(endpoint) do |connection|
  connection.use Middleware::Exceptions
end

In my projects, I typically do something like:

rescue Faraday::Error::ConnectionFailed => e
  url = env[:url].to_s.gsub(env[:url].path, '')
  $stderr.puts "The server at #{url} is either unavailable or is not currently accepting requests. Please try again in a few minutes."
end

Happy error handling!

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