Fix garage mc not getting default secret key set correctly

entrypoint/src/cmd/entrypoint/garage.go

@@ -36,15 +36,12 @@ var subCmdGarageMC = subCmd{
 
 		s3APIAddr := hostBootstrap.ChooseGaragePeer().S3APIAddr()
 
-		if *keyID == "" || *keySecret == "" {
-
 		if *keyID == "" {
 			*keyID = hostBootstrap.Garage.GlobalBucketS3APICredentials.ID
 		}
 
 		if *keySecret == "" {
-				*keyID = hostBootstrap.Garage.GlobalBucketS3APICredentials.Secret
+			*keySecret = hostBootstrap.Garage.GlobalBucketS3APICredentials.Secret
-			}
 		}
 
 		args := flags.Args()
@@ -56,13 +53,15 @@ var subCmdGarageMC = subCmd{
 		args = append([]string{"mc"}, args...)
 
 		var (
+			mcHostVar = fmt.Sprintf(
+				"MC_HOST_garage=http://%s:%s@%s",
+				*keyID, *keySecret, s3APIAddr,
+			)
+
 			binPath = filepath.Join(envAppDirPath, "bin/mc")
 			cliEnv  = append(
 				os.Environ(),
-				fmt.Sprintf(
+				mcHostVar,
-					"MC_HOST_garage=http://%s:%s@%s",
-					*keyID, *keySecret, s3APIAddr,
-				),
 
 				// The garage docs say this is necessary, though nothing bad
 				// seems to happen if we leave it out *shrug*

entrypoint/src/cmd/entrypoint/garage_util.go

@@ -265,9 +265,14 @@ func garageApplyLayout(
 
 			id := bootstrapGarageHostForAlloc(thisHost, alloc).ID
 
+			zone := hostName
+			if alloc.Zone != "" {
+				zone = alloc.Zone
+			}
+
 			clusterLayout[id] = peerLayout{
 				Capacity: alloc.Capacity / 100,
-				Zone:     hostName,
+				Zone:     zone,
 				Tags:     []string{},
 			}
 		}

entrypoint/src/daemon/config.go

@@ -36,6 +36,10 @@ type ConfigStorageAllocation struct {
 	S3APIPort int    `yaml:"s3_api_port"`
 	RPCPort   int    `yaml:"rpc_port"`
 	AdminPort int    `yaml:"admin_port"`
+
+	// Zone is a secret option which makes it easier to test garage bugs, but
+	// which we don't want users to otherwise know about.
+	Zone string `yaml:"zone"`
 }
 
 // Config describes the structure of the daemon config file.