Rename controller to nginx

controllers/nginx/nginx/command.go

@@ -0,0 +1,110 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 nginx
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"os/exec"
+
+	"github.com/golang/glog"
+
+	"k8s.io/kubernetes/pkg/healthz"
+)
+
+// Start starts a nginx (master process) and waits. If the process ends
+// we need to kill the controller process and return the reason.
+func (ngx *Manager) Start() {
+	glog.Info("Starting NGINX process...")
+	cmd := exec.Command("nginx")
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Start(); err != nil {
+		glog.Errorf("nginx error: %v", err)
+	}
+
+	if err := cmd.Wait(); err != nil {
+		glog.Errorf("nginx error: %v", err)
+	}
+}
+
+// CheckAndReload verify if the nginx configuration changed and sends a reload
+//
+// the master process receives the signal to reload configuration, it checks
+// the syntax validity of the new configuration file and tries to apply the
+// configuration provided in it. If this is a success, the master process starts
+// new worker processes and sends messages to old worker processes, requesting them
+// to shut down. Otherwise, the master process rolls back the changes and continues
+// to work with the old configuration. Old worker processes, receiving a command to
+// shut down, stop accepting new connections and continue to service current requests
+// until all such requests are serviced. After that, the old worker processes exit.
+// http://nginx.org/en/docs/beginners_guide.html#control
+func (ngx *Manager) CheckAndReload(cfg nginxConfiguration, ingressCfg IngressConfig) {
+	ngx.reloadRateLimiter.Accept()
+
+	ngx.reloadLock.Lock()
+	defer ngx.reloadLock.Unlock()
+
+	newCfg, err := ngx.writeCfg(cfg, ingressCfg)
+
+	if err != nil {
+		glog.Errorf("failed to write new nginx configuration. Avoiding reload: %v", err)
+		return
+	}
+
+	if newCfg {
+		if err := ngx.shellOut("nginx -s reload"); err == nil {
+			glog.Info("change in configuration detected. Reloading...")
+		}
+	}
+}
+
+// shellOut executes a command and returns its combined standard output and standard
+// error in case of an error in the execution
+func (ngx *Manager) shellOut(cmd string) error {
+	out, err := exec.Command("sh", "-c", cmd).CombinedOutput()
+	if err != nil {
+		glog.Errorf("failed to execute %v: %v", cmd, string(out))
+		return err
+	}
+
+	return nil
+}
+
+// check to verify Manager implements HealthzChecker interface
+var _ healthz.HealthzChecker = Manager{}
+
+// Name returns the healthcheck name
+func (ngx Manager) Name() string {
+	return "NGINX"
+}
+
+// Check returns if the nginx healthz endpoint is returning ok (status code 200)
+func (ngx Manager) Check(_ *http.Request) error {
+	res, err := http.Get("http://127.0.0.1:8080/healthz")
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode != 200 {
+		return fmt.Errorf("NGINX is unhealthy")
+	}
+
+	return nil
+}