Added UTs

Signed-off-by: Athishpranav2003 <athishanna@gmail.com>

spec/fluent/plugin/in_prometheus_spec.rb

@@ -45,6 +45,24 @@
         expect(driver.instance.metrics_path).to eq('/_test')
       end
     end
+
+    describe 'content_encoding_identity' do
+      let(:config) { CONFIG + %[
+    content_encoding identity
+] }
+      it 'should be configurable' do
+        expect(driver.instance.content_encoding).to eq(:identity)
+      end
+    end
+
+    describe 'content_encoding_gzip' do
+      let(:config) { CONFIG + %[
+    content_encoding gzip
+] }
+      it 'should be configurable' do
+        expect(driver.instance.content_encoding).to eq(:gzip)
+      end
+    end
   end
 
   describe '#start' do
@@ -197,6 +215,40 @@
         end
       end
     end
+
+    context 'response content_encoding identity' do
+      let(:config) { LOCAL_CONFIG + %[
+        content_encoding identity
+  ] }
+      it 'exposes metric' do
+        driver.run(timeout: 1) do
+          registry = driver.instance.instance_variable_get(:@registry)
+          registry.counter(:test,docstring: "Testing metrics") unless registry.exist?(:test)
+          Net::HTTP.start("127.0.0.1", port) do |http|
+            req = Net::HTTP::Get.new("/metrics")
+            res = http.request(req)
+            expect(res.body).to include("test Testing metrics")
+          end
+        end
+      end
+    end
+
+    context 'response content_encoding gzip' do
+      let(:config) { LOCAL_CONFIG + %[
+        content_encoding gzip
+  ] }
+      it 'exposes metric' do
+        driver.run(timeout: 1) do
+          registry = driver.instance.instance_variable_get(:@registry)
+          registry.counter(:test,docstring: "Testing metrics") unless registry.exist?(:test)
+          Net::HTTP.start("127.0.0.1", port) do |http|
+            req = Net::HTTP::Get.new("/metrics")
+            res = http.request(req)
+            expect(res.body).to include("test Testing metrics")
+          end
+        end
+      end
+    end
   end
 
   describe '#run_multi_workers' do