check conflict between scale and container_name

Signed-off-by: Nicolas De Loof <[email protected]>

loader/validate.go

@@ -109,11 +109,23 @@ func checkConsistency(project *types.Project) error {
 
 		if s.Scale != nil && s.Deploy != nil {
 			if s.Deploy.Replicas != nil && *s.Scale != *s.Deploy.Replicas {
-				return errors.Wrap(errdefs.ErrInvalid, "can't set distinct values on 'scale' and 'deploy.replicas'")
+				return errors.Wrapf(errdefs.ErrInvalid,
+					"services.%s: can't set distinct values on 'scale' and 'deploy.replicas'",
+					s.Name)
 			}
 			s.Deploy.Replicas = s.Scale
 		}
 
+		if s.GetScale() > 1 && s.ContainerName != "" {
+			attr := "scale"
+			if s.Scale == nil {
+				attr = "deploy.replicas"
+			}
+			return errors.Wrapf(errdefs.ErrInvalid,
+				"services.%s: can't set container_name and %s as container name must be unique",
+				attr,
+				s.Name)
+		}
 	}
 
 	for name, secret := range project.Secrets {

types/types.go

@@ -169,6 +169,24 @@ func (s *ServiceConfig) NetworksByPriority() []string {
 	return sorted
 }
 
+func (s *ServiceConfig) GetScale() int {
+	if s.Scale != nil {
+		return *s.Scale
+	}
+	if s.Deploy != nil && s.Deploy.Replicas != nil {
+		// this should not be required as compose-go enforce consistency between scale anr replicas
+		return *s.Deploy.Replicas
+	}
+	return 1
+}
+
+func (s *ServiceConfig) SetScale(scale int) {
+	s.Scale = &scale
+	if s.Deploy != nil {
+		s.Deploy.Replicas = &scale
+	}
+}
+
 const (
 	// PullPolicyAlways always pull images
 	PullPolicyAlways = "always"