Antoine Leblanc cf531b05cb Rewrite Tracing to allow for only one TraceT in the entire stack. ... This PR is on top of #7789. ### Description This PR entirely rewrites the API of the Tracing library, to make `interpTraceT` a thing of the past. Before this change, we ran traces by sticking a `TraceT` on top of whatever we were doing. This had several major drawbacks: - we were carrying a bunch of `TraceT` across the codebase, and the entire codebase had to know about it - we needed to carry a second class constraint around (`HasReporterM`) to be able to run all of those traces - we kept having to do stack rewriting with `interpTraceT`, which went from inconvenient to horrible - we had to declare several behavioral instances on `TraceT m` This PR rewrite all of `Tracing` using a more conventional model: there is ONE `TraceT` at the bottom of the stack, and there is an associated class constraint `MonadTrace`: any part of the code that happens to satisfy `MonadTrace` is able to create new traces. We NEVER have to do stack rewriting, `interpTraceT` is gone, and `TraceT` and `Reporter` become implementation details that 99% of the code is blissfully unaware of: code that needs to do tracing only needs to declare that the monad in which it operates implements `MonadTrace`. In doing so, this PR revealed **several bugs in the codebase**: places where we were expecting to trace something, but due to the default instance of `HasReporterM IO` we would actually not do anything. This PR also splits the code of `Tracing` in more byte-sized modules, with the goal of potentially moving to `server/lib` down the line. ### Remaining work This PR is a draft; what's left to do is: - [x] make Pro compile; i haven't updated `HasuraPro/Main` yet - [x] document Tracing by writing a note that explains how to use the library, and the meaning of "reporter", "trace" and "span", as well as the pitfalls - [x] discuss some of the trade-offs in the implementation, which is why i'm opening this PR already despite it not fully building yet - [x] it depends on #7789 being merged first PR-URL: https://github.com/hasura/graphql-engine-mono/pull/7791 GitOrigin-RevId: cadd32d039134c93ddbf364599a2f4dd988adea8		2023-03-13 17:38:39 +00:00
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Metadata	server: plumb StoredIntrospection while building the Schema Cache	2023-01-20 14:52:36 +00:00
MetadataAPI	harmonize network manager handling	2023-02-22 15:55:54 +00:00
SchemaCache	Rewrite Tracing to allow for only one TraceT in the entire stack.	2023-03-13 17:38:39 +00:00
Metadata.hs	scaffolding for remote-schemas module	2022-10-21 03:15:04 +00:00
MetadataAPI.hs	scaffolding for remote-schemas module	2022-10-21 03:15:04 +00:00
SchemaCache.hs	scaffolding for remote-schemas module	2022-10-21 03:15:04 +00:00