Refactor Clarifai class

lib/clarifai.rb

@@ -2,43 +2,48 @@ require "base64"
 require "http"
 
 class Clarifai
-  KEY = ENV.fetch("CLARIFAI_API_KEY").freeze
+  API_KEY = ENV.fetch("CLARIFAI_API_KEY").freeze
   API_URL = "https://api.clarifai.com/v2/models/" \
             "aaa03c23b3724a16a56b629203edc62c/outputs".freeze
 
-  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))
+  def tags
+    @tags ||= extract_tags(JSON.parse(post_image.body))
   end
 
+  private
+
   def extract_tags(response_hash)
-    @tags = response_hash["outputs"][0]["data"]["concepts"].map do |concept|
+    response_hash["outputs"][0]["data"]["concepts"].map do |concept|
       concept["name"]
     end
   end
+
+  def post_image
+    HTTP.
+      headers(headers).
+      post(API_URL, json: payload)
+  end
+
+  def headers
+    {
+      "Authorization": "Key #{API_KEY}",
+      "Content-Type": "application/json",
+    }
+  end
+
+  def payload
+    { "inputs": [{ "data": { "image": { "base64": image_base64 } } }] }
+  end
+
+  def image_base64
+    Base64.encode64(image_file)
+  end
+
+  def image_file
+    File.read(@image_path)
+  end
 end

spec/lib/clarifai_spec.rb

@@ -3,37 +3,30 @@ ENV["CLARIFAI_API_KEY"] = "1234"
 require "clarifai"
 
 describe Clarifai do
-  describe ".predict" do
+  describe ".tags" do
     it "predicts tags for our image" do
-      stub_body = {
+      WebMock.
+        stub_request(:post, Clarifai::API_URL).
+        to_return(status: 200, body: stub_body.to_json)
+
+      clarifai_image = Clarifai.new("spec/fixtures/spectrum.jpg")
+
+      expect(clarifai_image.tags).to eq(["computer", "technology"])
+    end
+
+    def stub_body
+      {
         "outputs": [
           {
             "data": {
               "concepts": [
-                {
-                  "id": "ai_PpTcwbdQ",
-                  "name": "computer",
-                  "value": 0.96887743,
-                },
-                {
-                  "id": "ai_62K34TR4",
-                  "name": "technology",
-                  "value": 0.96544206,
-                },
+                { "name": "computer", "value": 0.96887743 },
+                { "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