Fix placement option (#56)

* Fix placement option

* Update docs for placement_option

Author: skirsten

docs/resources/instance.md

@@ -49,7 +49,7 @@ resource "genesiscloud_instance" "example" {
 - `password` (String, Sensitive) The password to access the instance. Your password must have upper and lower chars, digits and length between 8-72. **Please Note**: Only one of `ssh_keys` or `password` can be provided. Password is less secure - we recommend you use an SSH key-pair.
   - If the value of this attribute changes, Terraform will destroy and recreate the resource.
   - The string length must be at least 16.
-- `placement_option` (String) The placement option identifier in which instances are physically located relative to each other within a zone.
+- `placement_option` (String) The placement option identifier in which instances are physically located relative to each other within a zone. For example A or B.
   - If the value of this attribute changes, Terraform will destroy and recreate the resource.
 - `security_group_ids` (Set of String) The security groups of the instance. If not provided will be set to the default security group.
 - `ssh_key_ids` (Set of String) The ssh keys of the instance.

internal/provider/instance_resource.go

@@ -122,7 +122,7 @@ func (r *InstanceResource) Schema(ctx context.Context, req resource.SchemaReques
 				},
 			}),
 			"placement_option": resourceenhancer.Attribute(ctx, schema.StringAttribute{
-				MarkdownDescription: "The placement option identifier in which instances are physically located relative to each other within a zone.",
+				MarkdownDescription: "The placement option identifier in which instances are physically located relative to each other within a zone. For example A or B.",
 				Optional:            true,
 				Computed:            true,
 				PlanModifiers: []planmodifier.String{
@@ -284,7 +284,10 @@ func (r *InstanceResource) Create(ctx context.Context, req resource.CreateReques
 	}
 
 	body.Region = genesiscloud.Region(data.Region.ValueString())
-	body.PlacementOption = pointer(data.PlacementOption.ValueString())
+
+	if !data.PlacementOption.IsNull() && !data.PlacementOption.IsUnknown() {
+		body.PlacementOption = pointer(data.PlacementOption.ValueString())
+	}
 
 	response, err := r.client.CreateInstanceWithResponse(ctx, body)
 	if err != nil {