Google Cloud Vision API client

google_cloud_vision_api.rb

require 'openssl'
require "base64"
require 'net/http'
require 'json'

image_path = ARGV[0]
puts "Reading image #{image_path}..."
b64_data = Base64.encode64(File.open(image_path, "rb").read)

api_key = ENV.fetch('GOOGLE_CLOUD_VISION_API_KEY') { raise 'Missing env variable GOOGLE_CLOUD_VISION_API_KEY' }

url = "https://vision.googleapis.com/v1/images:annotate?key=#{api_key}"
data = {
  "requests": [
    {
      "image": {
        "content": b64_data
      },
      "features": [
        {
          "type": "TEXT_DETECTION",
          "maxResults": 1
        }
      ]
    }
  ]
}.to_json

uri = URI(url)
req = Net::HTTP::Post.new(uri, initheader = {'Content-Type' => 'application/json'})
req.body = data
res = Net::HTTP.new(uri.host, uri.port)
res.use_ssl = true

res.start do |http| 
  resp = http.request(req)
  json = JSON.parse(resp.body)
  res = if json && json["responses"] && json["responses"][0]["textAnnotations"] && json["responses"][0]["textAnnotations"][0]["description"]
          json["responses"][0]["textAnnotations"][0]["description"]
        else
          ":-("
        end
  puts res
end