Storing values in a context is quite flexible, but comes without strict type safety, and obscures the API. So what can we do about this? First, for type safety, we’re limited to runtime assertions: userID := ctx.Value(userIDKey).(string) But this can panic if we ever get an unexpected value (or even nil). So to make it safer, we can use the two-variable assignment form, which yields a bool indicating success: userID, ok := ctx.
