Add liveness\readiness probe for s3 api handler on /status path

Makefile

@@ -33,7 +33,7 @@ deps:
 	rm -rf /home/travis/gopath/src/github.com/coreos/etcd/vendor/golang.org/x/net/trace
 	rm -rf /home/travis/gopath/src/go.etcd.io/etcd/vendor/golang.org/x/net/trace
 
-build: deps
+build:
 	go build $(GO_FLAGS) -ldflags "$(LDFLAGS)" -o $(BINARY) $(SOURCE_DIR)
 
 install: deps

weed/s3api/s3api_server.go

@@ -2,12 +2,12 @@ package s3api
 
 import (
 	"fmt"
-	"github.com/chrislusf/seaweedfs/weed/filer"
-	. "github.com/chrislusf/seaweedfs/weed/s3api/s3_constants"
 	"net/http"
 	"strings"
 	"time"
 
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	. "github.com/chrislusf/seaweedfs/weed/s3api/s3_constants"
 	"github.com/gorilla/mux"
 	"google.golang.org/grpc"
 )
@@ -44,6 +44,10 @@ func NewS3ApiServer(router *mux.Router, option *S3ApiServerOption) (s3ApiServer
 func (s3a *S3ApiServer) registerRouter(router *mux.Router) {
 	// API Router
 	apiRouter := router.PathPrefix("/").Subrouter()
+
+	// Readiness Probe
+	apiRouter.Methods("GET").Path("/status").HandlerFunc(s3a.StatusHandler)
+
 	var routers []*mux.Router
 	if s3a.option.DomainName != "" {
 		domainNames := strings.Split(s3a.option.DomainName, ",")

weed/s3api/s3api_status_handlers.go

@@ -0,0 +1,8 @@
+package s3api
+
+import "net/http"
+
+func (s3a *S3ApiServer) StatusHandler(w http.ResponseWriter, r *http.Request) {
+	// write out the response code and content type header
+	writeSuccessResponseEmpty(w)
+}