Use nginx upstreams and reload only if configuration changes

controllers/nginx-third-party/nginx/command.go

@@ -52,17 +52,20 @@ func (ngx *NginxManager) Start() {
 // 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 *NginxManager) Reload(cfg *nginxConfiguration, servicesL4 []Service) {
+func (ngx *NginxManager) CheckAndReload(cfg *nginxConfiguration, upstreams []Upstream, servers []Server, servicesL4 []Service) {
 	ngx.reloadLock.Lock()
 	defer ngx.reloadLock.Unlock()
 
-	if err := ngx.writeCfg(cfg, servicesL4); err != nil {
+	newCfg, err := ngx.writeCfg(cfg, upstreams, servers, servicesL4)
+	if err != nil {
 		glog.Errorf("Failed to write new nginx configuration. Avoiding reload: %v", err)
 		return
 	}
 
-	if err := ngx.shellOut("nginx -s reload"); err == nil {
-		glog.Info("Change in configuration detected. Reloading...")
+	if newCfg {
+		if err := ngx.shellOut("nginx -s reload"); err == nil {
+			glog.Info("Change in configuration detected. Reloading...")
+		}
 	}
 }
 

controllers/nginx-third-party/nginx/nginx.go

@@ -0,0 +1,92 @@
+package nginx
+
+// NGINXController Updates NGINX configuration, starts and reloads NGINX
+type NGINXController struct {
+	resolver       string
+	nginxConfdPath string
+	nginxCertsPath string
+	local          bool
+}
+
+// IngressNGINXConfig describes an NGINX configuration
+type IngressNGINXConfig struct {
+	Upstreams []Upstream
+	Servers   []Server
+}
+
+// Upstream describes an NGINX upstream
+type Upstream struct {
+	Name     string
+	Backends []UpstreamServer
+}
+
+type UpstreamByNameServers []Upstream
+
+func (c UpstreamByNameServers) Len() int      { return len(c) }
+func (c UpstreamByNameServers) Swap(i, j int) { c[i], c[j] = c[j], c[i] }
+func (c UpstreamByNameServers) Less(i, j int) bool {
+	return c[i].Name < c[j].Name
+}
+
+// UpstreamServer describes a server in an NGINX upstream
+type UpstreamServer struct {
+	Address string
+	Port    string
+}
+
+type UpstreamServerByAddrPort []UpstreamServer
+
+func (c UpstreamServerByAddrPort) Len() int      { return len(c) }
+func (c UpstreamServerByAddrPort) Swap(i, j int) { c[i], c[j] = c[j], c[i] }
+func (c UpstreamServerByAddrPort) Less(i, j int) bool {
+	iName := c[i].Address
+	jName := c[j].Address
+	if iName != jName {
+		return iName < jName
+	}
+
+	iU := c[i].Port
+	jU := c[j].Port
+	return iU < jU
+}
+
+// Server describes an NGINX server
+type Server struct {
+	Name              string
+	Locations         []Location
+	SSL               bool
+	SSLCertificate    string
+	SSLCertificateKey string
+}
+
+type ServerByNamePort []Server
+
+func (c ServerByNamePort) Len() int      { return len(c) }
+func (c ServerByNamePort) Swap(i, j int) { c[i], c[j] = c[j], c[i] }
+func (c ServerByNamePort) Less(i, j int) bool {
+	return c[i].Name < c[j].Name
+}
+
+// Location describes an NGINX location
+type Location struct {
+	Path     string
+	Upstream Upstream
+}
+
+type locByPathUpstream []Location
+
+func (c locByPathUpstream) Len() int      { return len(c) }
+func (c locByPathUpstream) Swap(i, j int) { c[i], c[j] = c[j], c[i] }
+func (c locByPathUpstream) Less(i, j int) bool {
+	return c[i].Path < c[j].Path
+}
+
+// NewUpstreamWithDefaultServer creates an upstream with the default server.
+// proxy_pass to an upstream with the default server returns 502.
+// We use it for services that have no endpoints
+func NewUpstreamWithDefaultServer(name string) Upstream {
+	return Upstream{
+		Name:     name,
+		Backends: []UpstreamServer{UpstreamServer{Address: "127.0.0.1", Port: "8181"}},
+	}
+}

controllers/nginx-third-party/nginx/template.go

@@ -60,10 +60,10 @@ func (ngx *NginxManager) loadTemplate() {
 	ngx.template = tmpl
 }
 
-func (ngx *NginxManager) writeCfg(cfg *nginxConfiguration, servicesL4 []Service) error {
+func (ngx *NginxManager) writeCfg(cfg *nginxConfiguration, upstreams []Upstream, servers []Server, servicesL4 []Service) (bool, error) {
 	file, err := os.Create(ngx.ConfigFile)
 	if err != nil {
-		return err
+		return false, err
 	}
 
 	fromMap := structs.Map(cfg)
@@ -72,6 +72,8 @@ func (ngx *NginxManager) writeCfg(cfg *nginxConfiguration, servicesL4 []Service)
 
 	conf := make(map[string]interface{})
 	conf["sslCertificates"] = ngx.sslCertificates
+	conf["upstreams"] = upstreams
+	conf["servers"] = servers
 	conf["tcpServices"] = servicesL4
 	conf["defBackend"] = ngx.defBackend
 	conf["defResolver"] = ngx.defResolver
@@ -94,8 +96,8 @@ func (ngx *NginxManager) writeCfg(cfg *nginxConfiguration, servicesL4 []Service)
 
 	err = ngx.template.Execute(file, conf)
 	if err != nil {
-		return err
+		return false, err
 	}
 
-	return nil
+	return true, nil
 }

controllers/nginx-third-party/nginx/utils.go

@@ -17,7 +17,6 @@ limitations under the License.
 package nginx
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
@@ -28,27 +27,6 @@ import (
 	"github.com/golang/glog"
 )
 
-// SyncIngress creates a GET request to nginx to indicate that is required to refresh the Ingress rules.
-func (ngx *NginxManager) SyncIngress(ingList []interface{}) error {
-	encData, _ := json.Marshal(ingList)
-	req, err := http.NewRequest("POST", "http://127.0.0.1:8080/update-ingress", bytes.NewBuffer(encData))
-	req.Header.Set("Content-Type", "application/json")
-	res, err := http.DefaultClient.Do(req)
-	if err != nil {
-		return err
-	}
-	defer res.Body.Close()
-
-	if res.StatusCode != 200 {
-		body, _ := ioutil.ReadAll(res.Body)
-		glog.Errorf("Error: %v", string(body))
-		return fmt.Errorf("nginx status is unhealthy")
-	}
-
-	return nil
-
-}
-
 // IsHealthy checks if nginx is running
 func (ngx *NginxManager) IsHealthy() error {
 	res, err := http.Get("http://127.0.0.1:8080/healthz")