Dynamic control over tracing-flame span name

[jsouto18]

Feature Request

Allow for dynamic control over the written span name.

Crates

tracing-flame

Motivation

Currently tracing span names must be 'static. In the use case of running tracing spans over tests configured dynamically we're limited to the same span name.

Proposal

I believe this can be implemented without breaking changes by:

• Adding a new field to the Config struct defining the name of the span field to be considered as the span name replacement. Here
• Capturing this field if present and replacing the name write call. Here

I see no drawback for this implementation as of now.

I'm also happy to come up with the PR if this is accepted as a useful feature 😁

[mladedav]

To be clear, what you're proposing is to only change the output of tracing-flame span name, right?

So for example fmt would still output the 'static name and the span names may not be the same for tracing-flame output and other outputs if overridden, right?

[jsouto18]

Correct @mladedav!