Remove GenericController and add tests

pkg/ingress/controller/checker.go

@@ -0,0 +1,68 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package controller
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/golang/glog"
+	"github.com/ncabatoff/process-exporter/proc"
+)
+
+// Name returns the healthcheck name
+func (n NGINXController) Name() string {
+	return "Ingress Controller"
+}
+
+// Check returns if the nginx healthz endpoint is returning ok (status code 200)
+func (n NGINXController) Check(_ *http.Request) error {
+	res, err := http.Get(fmt.Sprintf("http://0.0.0.0:%v%v", n.cfg.ListenPorts.Status, ngxHealthPath))
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+	if res.StatusCode != 200 {
+		return fmt.Errorf("ingress controller is not healthy")
+	}
+
+	// check the nginx master process is running
+	fs, err := proc.NewFS("/proc")
+	if err != nil {
+		glog.Errorf("%v", err)
+		return err
+	}
+	f, err := ioutil.ReadFile("/run/nginx.pid")
+	if err != nil {
+		glog.Errorf("%v", err)
+		return err
+	}
+	pid, err := strconv.Atoi(strings.TrimRight(string(f), "\r\n"))
+	if err != nil {
+		return err
+	}
+	_, err = fs.NewProc(pid)
+	if err != nil {
+		glog.Errorf("%v", err)
+		return err
+	}
+
+	return nil
+}