From 10a41c914e785c1118c1053901999b68997fd4ae Mon Sep 17 00:00:00 2001
From: Jeff Mitchell <jeffrey.mitchell@gmail.com>
Date: Thu, 24 Sep 2020 13:14:45 -0400
Subject: [PATCH] Force worker to use the local controller when running in
 combined mode (#429)

---
 internal/cmd/commands/server/server.go | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/internal/cmd/commands/server/server.go b/internal/cmd/commands/server/server.go
index 31b2dcdbaa..ebe4935c38 100644
--- a/internal/cmd/commands/server/server.go
+++ b/internal/cmd/commands/server/server.go
@@ -172,7 +172,7 @@ func (c *Command) Run(args []string) int {
 	}
 
 	// Perform controller-specific listener checks here before setup
-	var foundCluster bool
+	var clusterAddr string
 	var foundApi bool
 	var foundProxy bool
 	for _, lnConfig := range c.Config.Listeners {
@@ -185,7 +185,10 @@ func (c *Command) Run(args []string) int {
 			purpose := lnConfig.Purpose[0]
 			switch purpose {
 			case "cluster":
-				foundCluster = true
+				clusterAddr = lnConfig.Address
+				if clusterAddr == "" {
+					clusterAddr = "127.0.0.1:9201"
+				}
 			case "api":
 				foundApi = true
 			case "proxy":
@@ -205,7 +208,7 @@ func (c *Command) Run(args []string) int {
 			c.UI.Error(`Config activates controller but no listener with "api" purpose found`)
 			return 1
 		}
-		if !foundCluster {
+		if clusterAddr == "" {
 			c.UI.Error(`Config activates controller but no listener with "cluster" purpose found`)
 			return 1
 		}
@@ -215,6 +218,20 @@ func (c *Command) Run(args []string) int {
 			c.UI.Error(`Config activates worker but no listener with "proxy" purpose found`)
 			return 1
 		}
+		if c.Config.Controller != nil {
+			switch len(c.Config.Worker.Controllers) {
+			case 0:
+			case 1:
+				if c.Config.Worker.Controllers[0] == clusterAddr {
+					break
+				}
+				fallthrough
+			default:
+				c.UI.Error(`When running a combined controller and worker, it's invalid to specify a "controllers" key in the worker block with any value other than the controller cluster address`)
+				return 1
+			}
+			c.Config.Worker.Controllers = []string{clusterAddr}
+		}
 	}
 	if err := c.SetupListeners(c.UI, c.Config.SharedConfig, []string{"api", "cluster", "proxy"}); err != nil {
 		c.UI.Error(err.Error())