Replit
api
Request Validation Failed on Replit
API returns 400 Bad Request with validation errors. Request payload doesn't match expected format or constraints.
Request validation catches invalid or malformed data before processing.
Error Messages You Might See
400 Bad Request
validation failed
field validation error
Common Causes
- Missing required fields in request body
- Field type mismatch (string instead of number)
- Constraint violation (length, pattern, range)
- Unknown fields in request (if validation strict)
- Date format incorrect
How to Fix It
For Spring Boot, use @Valid with bean validation annotations (@NotNull, @Size, @Email). Check validation error messages in response. Use @JsonIgnoreProperties(ignoreUnknown=false) to reject unknown fields. Test request format with Postman. Return detailed validation error responses to client.
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Nam Tran
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You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.
Get HelpFrequently Asked Questions
How do I add validation?
Use annotations: @NotNull, @Size(min=1, max=100), @Email on fields
How do I return validation errors?
@ExceptionHandler catches MethodArgumentNotValidException and returns errors