AddCors : AddCors is the middleware which will add the cors in the response and response with status ok on preflight request.

AddLogger logs request/response pair.

AddRequestID is a middleware that injects a request ID into the context of each request.

ChangeContext : ChangeContext is responsible to add the authorization token to the context so that in grpc server we can easily get authentication token and verify the authentication token.

GetReqID returns a request ID from the given context if one is present.

RequestIDKey is the key that holds th unique request ID in a request context.