(*) Tracing

TODO

Tracing Execution Time

The @traceExecutionTime directive tracks how much time it takes to resolve a field (including all the involved directives), and adds the result under entry extensions.traces in the response.

As an example, we can use it to measure how fast is the @translate directive (which connects to the Google Translation API), and how fast it is after applying @cache to the translation (so that it doesn't connect to the external API anymore). For that, we execute this query with @traceExecutionTime first, and within 10 seconds again:

query {
  posts(limit:3) {
    id
    title @translate(from:"en", to:"es") @cache(time:10) @traceExecutionTime
  }
}

For the first execution, the logs inform us that resolving the field containing the @translate directive took 80.111 milliseconds to execute:

For the second execution, the logs indicate that the field was resolved in less than 1 millisecond:

The @traceExecutionTime directive then shows that caching results improve the performance of the API.

Configuration

Environment variables

Environment variable	Description	Default
SHOW_TRACES_IN_RESPONSE	Print the traces under entry extensions.traces	false
SEND_TRACES_TO_LOG	Print a human-readable summary of the traces under entry extensions.logs	false