Is tracing intended to be used as I am using it? How can I trace errors chain? - rust

Question

I'm using async-graphql and axum.
This is a reproduction of the issue: https://github.com/frederikhors/iss-async-graphql-error-handling.
To start:
cargo run
If you open the GraphiQL client at http://localhost:8000, you can use the below query to simulate what I'm trying to understand:
mutation {
mutateWithError
}
The backend response is:
{
"data": null,
"errors": [
{
"message": "I cannot mutate now, sorry!",
"locations": [
/*...*/
],
"path": ["mutateWithError"]
}
]
}
I like this, but what I don't understand is the tracing part:
2022-09-29T17:01:14.249236Z INFO async_graphql::graphql:84: close, time.busy: 626µs, time.idle: 14.3µs
in async_graphql::graphql::parse
in async_graphql::graphql::request
2022-09-29T17:01:14.252493Z INFO async_graphql::graphql:108: close, time.busy: 374µs, time.idle: 8.60µs
in async_graphql::graphql::validation
in async_graphql::graphql::request
2022-09-29T17:01:14.254592Z INFO async_graphql::graphql:146: error, error: I cannot mutate now, sorry!
in async_graphql::graphql::field with path: mutateWithError, parent_type: Mutation, return_type: String!
in async_graphql::graphql::execute
in async_graphql::graphql::request
2022-09-29T17:01:14.257389Z INFO async_graphql::graphql:136: close, time.busy: 2.85ms, time.idle: 30.8µs
in async_graphql::graphql::field with path: mutateWithError, parent_type: Mutation, return_type: String!
in async_graphql::graphql::execute
in async_graphql::graphql::request
2022-09-29T17:01:14.260729Z INFO async_graphql::graphql:122: close, time.busy: 6.31ms, time.idle: 7.80µs
in async_graphql::graphql::execute
in async_graphql::graphql::request
2022-09-29T17:01:14.264606Z INFO async_graphql::graphql:56: close, time.busy: 16.1ms, time.idle: 22.6µs
in async_graphql::graphql::request
Do you see the INFO async_graphql::graphql:146: error, error: I cannot mutate now, sorry!?
Why is it an INFO event? I would expect it to be an ERROR event.
And where is the innter error this is a DB error?
Code
The code is very simple:
pub struct Mutation;
#[Object]
impl Mutation {
async fn mutate_with_error(&self) -> async_graphql::Result<String> {
let new_string = mutate_with_error().await?;
Ok(new_string)
}
}
async fn mutate_with_error() -> anyhow::Result<String> {
match can_i_mutate_on_db().await {
Ok(s) => Ok(s),
Err(err) => Err(err.context("I cannot mutate now, sorry!")),
}
}
async fn can_i_mutate_on_db() -> anyhow::Result<String> {
bail!("this is a DB error!")
}
async fn graphql_handler(
schema: Extension<Schema<Query, Mutation, EmptySubscription>>,
req: GraphQLRequest,
) -> GraphQLResponse {
schema.execute(req.into_inner()).await.into()
}