WIP: Add Clarifai class for image classification

Gemfile

@@ -31,4 +31,5 @@ group :test do
   gem "launchy"
   gem "rspec-rails"
   gem "shoulda-matchers"
+  gem "webmock"
 end

Gemfile.lock

@@ -61,6 +61,8 @@ GEM
       xpath (~> 3.1)
     coderay (1.1.2)
     concurrent-ruby (1.0.5)
+    crack (0.4.3)
+      safe_yaml (~> 1.0.0)
     crass (1.0.4)
     debug_inspector (0.0.3)
     diff-lcs (1.3)
@@ -81,6 +83,7 @@ GEM
     ffi (1.9.25)
     globalid (0.4.1)
       activesupport (>= 4.2.0)
+    hashdiff (0.3.7)
     hashie (3.5.7)
     http (3.3.0)
       addressable (~> 2.3)
@@ -188,6 +191,7 @@ GEM
       rspec-mocks (~> 3.8.0)
       rspec-support (~> 3.8.0)
     rspec-support (3.8.0)
+    safe_yaml (1.0.4)
     sass (3.5.7)
       sass-listen (~> 4.0.0)
     sass-listen (4.0.0)
@@ -223,6 +227,10 @@ GEM
     unf (0.1.4)
       unf_ext
     unf_ext (0.0.7.5)
+    webmock (3.4.2)
+      addressable (>= 2.3.6)
+      crack (>= 0.3.2)
+      hashdiff
     websocket-driver (0.7.0)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.3)
@@ -252,6 +260,7 @@ DEPENDENCIES
   shoulda-matchers
   simple_form
   uglifier
+  webmock
 
 RUBY VERSION
    ruby 2.5.1p57

config/application.rb

@@ -19,5 +19,6 @@ module MyImages
     # The default locale is :en and all translations from config/locales/*.rb,yml are auto loaded.
     # config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*.{rb,yml}').to_s]
     # config.i18n.default_locale = :de
+    config.autoload_paths += %W(#{config.root}/lib)
   end
 end

lib/clarifai.rb

@@ -0,0 +1,43 @@
+require 'base64'
+require 'http'
+
+class Clarifai
+  KEY = ENV.fetch("CLARIFAI_API_KEY").freeze
+  API_URL =  "https://api.clarifai.com/v2/models/aaa03c23b3724a16a56b629203edc62c/outputs"
+
+  attr_reader :tags
+
+  def initialize(image_path)
+    @image_path = image_path
+  end
+
+  def predict!
+    headers = {
+      "Authorization": "Key #{KEY}",
+      "Content-Type": "application/json"
+    }
+    params = {
+      "inputs": [
+        {
+          "data": {
+            "image": {
+              "base64": Base64.encode64(File.read(@image_path))
+            }
+          }
+        }
+      ]
+    }
+
+    resp = HTTP.
+      headers(headers).
+      post(API_URL, json: params)
+
+    extract_tags(JSON.parse(resp.body))
+  end
+
+  def extract_tags(response_hash)
+    @tags = response_hash["outputs"][0]["data"]["concepts"].map do |concept|
+      concept["name"]
+    end
+  end
+end

spec/lib/clarifai_spec.rb

@@ -0,0 +1,41 @@
+require "spec_helper"
+ENV["CLARIFAI_API_KEY"] = "1234"
+require "clarifai"
+
+describe Clarifai do
+  describe ".predict" do
+    it "predicts tags for our image" do
+      stub_body = {
+        "outputs": [
+          {
+            "data": {
+              "concepts": [
+                {
+                  "id": "ai_PpTcwbdQ",
+                  "name": "computer",
+                  "value": 0.96887743
+                },
+                {
+                  "id": "ai_62K34TR4",
+                  "name": "technology",
+                  "value": 0.96544206
+                }
+              ]
+            }
+          }
+        ]
+      }.to_json
+
+      WebMock.
+        stub_request(:post, Clarifai::API_URL).
+        to_return(:status => 200, :body => stub_body)
+
+      clarifai_image = Clarifai.new("spec/fixtures/spectrum.jpg")
+      clarifai_image.predict!
+
+      expect(clarifai_image.tags).to eq(["computer", "technology"])
+    end
+  end
+end
+
+

spec/spec_helper.rb

@@ -1,3 +1,6 @@
+require 'webmock/rspec'
+WebMock.disable_net_connect!
+
 # This file was generated by the `rails generate rspec:install` command. Conventionally, all
 # specs live under a `spec` directory, which RSpec adds to the `$LOAD_PATH`.
 # The generated `.rspec` file contains `--require spec_helper` which will cause