Incorect behavior of plugin apollo-server-plugin-response-cache in case of validation error on client request

[kolegm]

Hey guys

I have a bug related to the plugin apollo-server-plugin-response-cache.

Expected:
When the client sends a not well-formed request, server must answers with GraphQL error and validation details. Example of correct answer
{ name: 'ValidationError', message: 'Cannot query field "accommodations_foo" on type "Query". Did you mean "accommodations"?', code: 'GRAPHQL_VALIDATION_FAILED' } [ 'Cannot query field "accommodations_foo" on type "Query". Did you mean "accommodations"?',

Actually:
The client received the bag. Trace:
{ name: 'TypeError', message: 'Cannot read property \'operation\' of undefined', code: 'INTERNAL_SERVER_ERROR' } [ 'TypeError: Cannot read property \'operation\' of undefined', at isGraphQLQuery (/home/***/node_modules/apollo-server-plugin-response-cache/src/ 2:36)', at Object.<anonymous> (/home/***/node_modules/apollo-server-plugin-response-cache/ s:224:16)', at Generator.next (<anonymous>)', at /home/***/node_modules/apollo-server-plugin-response-cache/dist/ApolloServerPlu at new Promise (<anonymous>)', at __awaiter (/home/***/node_modules/apollo-server-plugin-response-cache/dist/Apolo, at Object.willSendResponse (/home/***/node_modules/apollo-server-plugin-response-cache/dist/ApolloServerPluginResponseCache.js:92:28)',

Would be great to fix the logic here:

apollo-server/packages/apollo-server-plugin-response-cache/src/ApolloServerPluginResponseCache.ts

Line 132 in bfe900d

return requestContext.operation!.operation === 'query';

Example of fix (just add checking of existing the operation level:
function isGraphQLQuery(requestContext) { return requestContext.operation && requestContext.operation.operation === 'query'; }

By the way, I'm developing my service on JavaScript, not TypeScript. Maybe it will help you navigate the nature of the error