Fixing a null-body crash in the Formbricks survey SDK, found by Sentry

This is a submission for DEV's Summer Bug Smash: Clear the Lineup powered by Sentry . A survey widget should not be able to take down the page it is embedded on. This one could: a single API response with a null body threw an uncaught TypeError in the visitor's browser. Sentry's bot found it, filed it as a GitHub issue, and Seer pointed at the exact line. Here is the fix. Project Overview Formbricks is an open-source survey and experience-management platform. Websites and apps embed a small JavaScript SDK that loads a survey, shows it to a user, and posts the answers back to the Formbricks API. The SDK lives in the monorepo as two packages: @formbricks/js-core (the loader and command queue) and @formbricks/surveys (the survey renderer). Both talk to the backend through a shared makeRequest helper. Bug Fix or Performance Improvement I fixed issue #6581 , a production crash that Sentry filed automatically: Bug: API data is not always validated in the surveys package TypeError: Cannot read properties of null (reading 'data') The issue was opened automatically by sentry[bot] , and its body carries the Sentry-captured (minified) stack trace plus a link to the source event, FORMBRICKS-CLOUD-3VE . Sentry did not just record this crash, it reported it. The SDK calls makeRequest to load a workspace's environment state. That code parsed the HTTP response and immediately read .data off the result: const json = ( await response . json ()) as ApiResponse ; // ... const successResponse = json as ApiSuccessResponse < T > ; return ok ( successResponse . data ); Two things go wrong here: response.json() on a body of literal null returns JavaScript null . Reading null.data throws TypeError: Cannot read properties of null (reading 'data') . The error path had the same problem one line up: errorResponse.code on a null body throws reading 'code' . response.json() is not guarded at all. A non-JSON body (an empty response, or an HTML error page from a proxy or CDN) makes it throw an unhan