Commit Graph
5 Commits
Author SHA1 Message Date
Eliza Weisman 44f65afcc6 trace: Allow field names to be separated by .s (#1027)
## Motivation

In order to support conventions that add namespacing to `tokio-trace`
field names, it's necessary to accept at least one type of separator
character. Currently, the `tokio-trace` macros only accept valid Rust
identifiers, so there is no clear separator character for namespaced
conventions. See also #1018.

## Solution

This branch changes the single `ident` fragment matcher for field names
to match *one or more* `ident` fragments separated by `.` characters.

## Notes

The resulting key is still exposed to `tokio-trace-core` as a string
constant created by stringifying the dotted expression. However, if
`tokio-trace-core` were later to adopt a first class notion of
hierarchical field keys, we would be able to track that change in
`tokio-trace` as an implementation detail.

Closes #1018.
Closes #1022.

Signed-off-by: Eliza Weisman <[email protected]>
2019-04-03 14:44:11 -07:00
João Oliveira 597f271c08 trace: Remove default trace level and make levels mandatory on span! macro (#1025)
## Motivation 

Was determined that having the span! macro default to the TRACE level is
probably not ideal (see discussion on #952). 

Closes #1013

## Solution 

Remove default trace level and make log lvl mandatory on span! macro,
and add the respective `trace_span!`, `debug_span!`, `info_span!`,
`warn_span!` and `error_span!` macros that behave as span! macro, but
with defined log levels

## Notes 

I think this is it, also removed some captures that were repeated, and
some testcases that also seemed repeated after adding the mandatory log
level, but please review it, if more tests or examples are needed happy
to provide (tried to find a way to get the generated macros log level,
but didn't find one, if there is a way i can add tests to assert that
the generated macro has the matching log level ). thanks
2019-04-02 11:29:23 -07:00
Eliza Weisman d8177f81ac trace: Allow trace instrumentation to emit log records (#992)
## Motivation

`tokio-trace` currently offers a strategy for compatibility with the
`log` crate: its macros can be dropped in as a replacement for `log`'s
macros, and a subscriber can be used that translates trace events to log
records. However, this requires the application to be aware of
`tokio-trace` and manually set up this subscriber.

Many libraries currently emit `log` records, and would like to be able
to emit `tokio-trace` instrumentation instead. The `tokio` runtimes are
one such example. However, with the current log compatibility strategy,
replacing existing logging with trace instrumentation would break
`tokio`'s logs for any downstream user which is using only `log` and not
`tokio-trace`. It is desirable for libraries to have the option to emit
both `log` _and_ `tokio-trace` diagnostics from the same instrumentation
points.

## Solution

This branch adds a `log` feature flag to the `tokio-trace` crate, which
when set, causes `tokio-trace` instrumentation to emit log records as well
as `tokio-trace` instrumentation. 

## Notes

In order to allow spans to log their names when they are entered and 
exited even when the span is disabled, this branch adds an 
`&'static Metadata` to the `Span` type. This was previously stored in
the `Inner` type and was thus only present when the span was enabled.
This makes disabled spans one word longer, but enabled spans remain
the same size.

Fixes: #949

Signed-off-by: Eliza Weisman <[email protected]>
2019-03-26 16:43:05 -07:00
Son 1524ee4b60 trace: Add static level filtering (#987)
## Motivation

`tokio-trace` should have static verbosity level filtering, like the
`log` crate. The static max verbosity level should be controlled at
compile time with a set of features. It should be possible to set a
separate max level for release and debug mode builds.

## Solution

We can do this fairly similarly to how the `log` crate does it:
`tokio-trace` should export a constant whose value is set based on the
static max level feature flags. Then, we add an if statement to the
`span!` and `event!` macros which tests if that event or span's level
is enabled.

Closes #959
2019-03-25 15:19:20 -07:00
Eliza Weisman 4313d65b38 trace: Switch to using local_inner_macros for instrumentation API (#969)
## Motivation

Currently, it isn't possible to import individual macros from
`tokio-trace` using the macros 1.2 syntax:

```rust
use tokio_trace::{debug, info, span};
```

This is because these macros require that `callsite` and `enabled` are
imported as well.

## Solution

This branch resolves the problem by adding the [`local_inner_macros`]
attribute to the instrumentation API's macros. This allows other macros
from within the crate to be used without requiring them to be explicitly
imported. 

However, this also requires duplicating any macros from other sources
(such as std and `tokio-trace-core`) with wrappers due to the behaviour
of `local_inner_macros`. I've added these wrapper macros as well.

Since the macros got even longer as a result of this, I've moved them
to a separate file to make `lib.rs` easier to read. I've also wrapped
some very long lines in the macros, and removed the explicit drop of
the result of evaluating some event macros (it's no longer necessary
as all event macros now evaluate to `()`).

[`local_inner_macros`]: https://doc.rust-lang.org/nightly/edition-guide/rust-2018/macros/macro-changes.html#local-helper-macros

Fixes #968

Signed-off-by: Eliza Weisman <[email protected]>
2019-03-11 14:48:23 -07:00