LinkedIn WhereHows数据集页JSON解析错误排查求助

Hey there, let's break down this issue and figure out where to start troubleshooting!

The SyntaxError: JSON.parse: unexpected character error tells us that the WhereHows frontend tried to parse a response from the backend as JSON, but the content it got back wasn't valid JSON. Specifically, the 3rd line, first character broke JSON formatting rules.

Most likely, the backend API (the one fetching dataset entities) returned something that isn't standard JSON—like an HTML error page (404/500), plain-text error messages (Java stack traces, DB connection failures), or even empty content. The frontend's JSON.parse() call chokes on this non-JSON data, hence the error.

• First, inspect the actual API response
  Open your browser's DevTools, go to the Network tab, and find the API request that's failing (it should be related to fetching datasets/entities). Check the Response tab for that request:

  • If you see an HTML error page: The API path is probably misconfigured, or the backend service isn't running/routing correctly.
  • If you see plain-text error messages: The backend threw an exception when processing the request, and didn't return a proper JSON error response.
  • If the response is empty: Either the backend has no data to return, or your request isn't authorized (so the backend isn't sending any content back).

• Double-check your Play frontend configuration variables
  Since you mentioned having these configs, verify these critical settings:

  • ws.url: Make sure this points to the correct base URL of your WhereHows backend (e.g., http://your-server-ip:8080). No extra trailing slashes or typos here!
  • auth.enabled: If authentication is turned on, ensure frontend auth settings match the backend (e.g., OAuth, cookie-based auth) and that your session is properly authenticated when making the request.
  • API path configs: Check variables like api.datasets to confirm they match the actual API endpoints exposed by the backend.

• Check backend service status and logs

  • Confirm all WhereHows backend services (main app, metadata collectors, etc.) are running without crashes.
  • Dive into the backend log files (usually in the logs folder of your WhereHows installation directory). Search for logs related to the failing dataset API request—you might find exceptions like DB connection failures, missing metadata, or permission errors here.

• Verify if metadata exists
  Since this is your first time using WhereHows, you might not have imported any dataset metadata yet. Follow the official docs to run a metadata collection task (for Hive, MySQL, or your target data source) first. If there's no metadata, the backend might return content that doesn't fit the frontend's expected JSON structure.

• Rule out browser cache or CORS issues

  • Clear your browser cache or open the WhereHows UI in incognito mode—stale cached configs can sometimes cause unexpected issues.
  • If your frontend and backend are hosted on different domains/ports, make sure the backend has CORS (Cross-Origin Resource Sharing) enabled. Without this, the browser might block the request, leading to invalid or missing responses.

内容的提问来源于stack exchange，提问作者lampShadesDrifter