fix #28

Author: sisby-folk

platform_api/src/main/java/net/modfest/platform/service/SubmissionService.java

@@ -11,7 +11,9 @@
 import org.jspecify.annotations.Nullable;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Lazy;
+import org.springframework.http.HttpStatus;
 import org.springframework.stereotype.Service;
+import org.springframework.web.server.ResponseStatusException;
 
 import java.util.*;
 import java.util.stream.Collectors;
@@ -253,6 +255,11 @@ public SubmissionData makeSubmissionModrinth(String eventId, Set<UserData> autho
 			throw new RuntimeException("submission already exists");
 		}
 
+		if (project.sourceUrl == null || project.sourceUrl.isBlank()) {
+			throw new ResponseStatusException(HttpStatus.BAD_REQUEST,
+				"Modrinth submissions MUST have visible source code!");
+		}
+
 		var latest = getLatestModrinth(subId, eventService.getEventById(eventId), project.projectType);
 
 		if (project.iconUrl != null) {