twitter_photo_upload.rb

require 'base64'

class Provider < ActiveRecord::Base
  belongs_to :user

  def prepare_access_token(oauth_token, oauth_token_secret)
    token_hash = { oauth_token: oauth_token, oauth_token_secret: oauth_token_secret }
    access_token = OAuth::AccessToken.from_hash(TWITTER_APP, token_hash)
    access_token
  end

  def publish_status(status:, image: nil)
    access_token = generate_access_token
    params_url = "status=#{CGI.escape status}"
    if image.present?
      media_id = upload_photo(image)
      return nil unless media_id.present?
      params_url += "&media_ids=#{media_id}"
    end
    response = access_token.post("https://api.twitter.com/1.1/statuses/update.json?#{params_url}")
    data = JSON.parse(response.body)
    data['id']
  end

  def upload_photo(image)
    access_token = generate_access_token
    download_media("#{Rails.root}/tmp/#{image.model.photo_tweet_identifier}", image.url)
    response = access_token.post('https://upload.twitter.com/1.1/media/upload.json', 'media_data' => Base64.encode64(File.open("#{Rails.root}/tmp/#{image.model.photo_tweet_identifier}").read), 'Content-Type' => 'multipart/form-data')
    data = JSON.parse(response.body)
    data['media_id']
  end

  private

  def download_media(path, url)
    open(path, 'wb') do |file|
      file << open(url).read
    end
  end

  def generate_access_token
    Rails.env.production? ? prepare_access_token(token, secret) : FAKE_PROVIDER
  end
end