postgres: add --json body example to create-role help

cmd/workspace/postgres/overrides.go

@@ -0,0 +1,34 @@
+package postgres
+
+import (
+	"github.com/databricks/databricks-sdk-go/service/postgres"
+	"github.com/spf13/cobra"
+)
+
+// createRoleOverride appends an example body to the auto-generated help.
+// The --json flag binds to the inner Role object (CreateRoleRequest.Role,
+// JSON-tagged "role"), so users supply spec/name/etc. directly. Without an
+// example, the auto-generated `// TODO: complex arg: spec` flags leave no
+// hint about the body shape and the API's "Field 'role' is required" error
+// is unhelpful when the request body is wrong.
+func createRoleOverride(createRoleCmd *cobra.Command, _ *postgres.CreateRoleRequest) {
+	createRoleCmd.Long += `
+
+  Body shape (passed via --json): fields go directly on the Role object.
+  Do not wrap them in '{"role": ...}' — the CLI will strip the unknown
+  outer key and the server will reject the empty body with "Field 'role'
+  is required".
+
+  Example — create a service-principal-backed role:
+
+    databricks postgres create-role projects/<PROJECT_ID>/branches/<BRANCH_ID> \
+      --role-id <SP_CLIENT_ID> \
+      --json '{"spec": {"identity_type": "SERVICE_PRINCIPAL", "postgres_role": "<SP_CLIENT_ID>", "auth_method": "LAKEBASE_OAUTH_V1", "membership_roles": ["DATABRICKS_SUPERUSER"]}}'
+
+  See databricks-sdk-go/service/postgres.RoleRoleSpec for the full set of
+  spec fields.`
+}
+
+func init() {
+	createRoleOverrides = append(createRoleOverrides, createRoleOverride)
+}