DEFAULT_TIMEOUT is not passed to Faraday connection as an option

[SeanSmithers]

When HTTParty was replaced with Faraday (in #55) some HTTParty options were converted to constants (https://github.com/decision-labs/fcm/pull/55/files#diff-0068abed920b95db498a1c507ae5a10f86145599f5dd2431b36ccbf492d7fe7dL6-L10)

DEFAULT_TIMEOUT and FORMAT are now unused.

It would be great to pass DEFAULT_TIMEOUT as an option to Faraday, example:

  def for_uri(uri, extra_headers = {})
    connection = ::Faraday.new(:url => uri) do |faraday|
      faraday.adapter  Faraday.default_adapter
      faraday.options["timeout"] = DEFAULT_TIMEOUT
      faraday.headers["Content-Type"] = "application/json"
      faraday.headers["Authorization"] = "key=#{api_key}"
      extra_headers.each do |key, value|
        faraday.headers[key] = value
      end
    end
    yield connection
  end

A bonus would be to allow some way for consumers of FCM to be able to pass options like this in when initializing and have them passed to the underlying HTTP library.

[sabman]

I am thinking of adding support for .env and/or ENV variables to overwrite the defaults. Thoughts?

[SeanSmithers]

@sabman support for .env and/or ENV variables could help here, yes.

Would these variables allow a consumer to overwrite just the timeout option or would it be possible to overwrite a number of different options on the underlying HTTP library?, e.g. open_timeout as well (but perhaps even things like request/response logging)

[sabman]

Yes we can probably add other items too. Only thing I'd wanna ensure is avoid accidental name clashes. So maybe namespacing the environment variables with FCM_VAR_XXX might be the way to go.

[jensljungblad]

@sabman Could you do something similar to the elasticsearch gem?

Elasticsearch::Client.new(
  host: ENV.fetch("ELASTICSEARCH_HOST", nil),
  user: ENV.fetch("ELASTICSEARCH_USER", nil),
  password: ENV.fetch("ELASTICSEARCH_PASSWORD", nil),
  request_timeout: 10
) do |faraday|
  faraday.request(:instrumentation, name: "request.elasticsearch")
end

Giving access to the faraday object allows you to attach own instrumentation etc.

[Linuus]

The issue with DEFAULT_TIMEOUT not being used has been addressed in: #96