cleanup, ensure haproxy is running and disallow writes to followers

pkg/api/server.go

@@ -104,8 +104,9 @@ func NewServer(c *config.Config, log logr.Logger) (*Server, error) {
 	return s, nil
 }
 
-func (s *Server) UpdateDB(db *db.DB) error {
+func (s *Server) UpdateDB(db *db.DB, leader bool) error {
 	s.Data.DB = db
+	s.Data.Leader = leader
 	if s.Data.Net == nil {
 		na, err := netalloc.NewGenericAlloc(db, s.cidr)
 		if err != nil {

pkg/api/types/context.go

@@ -14,9 +14,10 @@ import (
 )
 
 type ContextData struct {
-	Net  netalloc.Allocator
-	DB   *db.DB
-	Auth *Auth
+	Net    netalloc.Allocator
+	DB     *db.DB
+	Auth   *Auth
+	Leader bool
 }
 
 func NewContext(w http.ResponseWriter, r *http.Request, data *ContextData, log logr.Logger) *Context {
@@ -42,6 +43,10 @@ type Context struct {
 	Log  logr.Logger
 }
 
+func (c *Context) Leader() bool {
+	return c.Data.Leader
+}
+
 // Method returns the request method
 func (c *Context) Method() string {
 	return c.Request.Method

pkg/api/types/error.go

@@ -43,4 +43,5 @@ var (
 	ErrMNA          = newError("method not allowed", http.StatusMethodNotAllowed)
 	ErrExists       = newError("resource already exists", http.StatusConflict)
 	ErrISE          = newError("internal server error", http.StatusInternalServerError)
+	ErrFollower     = newError("follower write forbidden", http.StatusForbidden)
 )

pkg/api/v1/server/handler.go

@@ -4,6 +4,7 @@ import (
 	//"golang.org/x/crypto/bcrypt"
 	//"net/http"
 	"encoding/json"
+	"errors"
 	"net"
 
 	"git.giftfish.de/ston1th/haproxy-lb/pkg/api/types"
@@ -11,6 +12,8 @@ import (
 	"git.giftfish.de/ston1th/haproxy-lb/pkg/cluster"
 )
 
+var errFollower = errors.New("follower write")
+
 func authHandler(h types.CtxHandler) types.CtxHandler {
 	return func(ctx *types.Context) {
 		user, pass, ok := ctx.Request.BasicAuth()
@@ -65,6 +68,11 @@ func lbHandler(ctx *types.Context) {
 		}
 		ctx.Body(b)
 	case "POST":
+		if !ctx.Leader() {
+			ctx.Log.Error(errFollower, "error writing config: i am a follower", "cluster", cl, "name", n)
+			ctx.Err(types.ErrFollower)
+			return
+		}
 		b, err := ctx.ReadBody()
 		if err != nil {
 			ctx.Log.Error(err, "error reading request body", "cluster", cl, "name", n)
@@ -123,6 +131,11 @@ func lbHandler(ctx *types.Context) {
 		}
 		ctx.OK()
 	case "DELETE":
+		if !ctx.Leader() {
+			ctx.Log.Error(errFollower, "error writing config: i am a follower", "cluster", cl, "name", n)
+			ctx.Err(types.ErrFollower)
+			return
+		}
 		if !ctx.Data.DB.LBExists(name) {
 			ctx.Err(types.ErrNotFound)
 			return
@@ -169,6 +182,11 @@ func lbClusterHandler(ctx *types.Context) {
 	case "GET":
 		ctx.JSON(lbList(m))
 	case "DELETE":
+		if !ctx.Leader() {
+			ctx.Log.Error(errFollower, "error writing config: i am a follower", "cluster", cl, "name", name)
+			ctx.Err(types.ErrFollower)
+			return
+		}
 		for name, _ := range m {
 			cidr, err := ctx.Data.DB.GetCIDR(name)
 			if err != nil && err != cluster.ErrKeyNotFound {