tracing-modality

tracing-modality provides a [tracing.rs] Subscriber for tracing systems written in [Rust] to Auxon Modality.

The quickest (and as of this version, only) way to get started is to let [TracingModality] register itself as the global default tracer, done most simply using [TracingModality::init()]

```rust use tracing::debug; use tracing_modality::TracingModality; use tracing::info;

fn main() { TracingModality::init().expect("init");

info!("my application has started");

} ```

Some basic configuration options are also available to be set at init with [TracingModality::init_with_options].

Usage

After the initial setup, shown above, this library is not used directly, but is used via macros defined in [tracing.rs]. These macros function much like the log crate's logging macros error, warn, info, debug and trace, except they also allow you to pass in structured values, in the form of fields, that are recorded in the trace data as standalone values rather than being stringified into the log message.

Additionally, tracing provides a similar set of macros for emitting spans: error_span, warn_span, info_span, debug_span, and trace_span. Spans are used to label regions of execution.

There are also many more ways to use tracing, such as the #[instrument] attribute and the Value trait. See tracing's documentation for the full API.

Metadata and Fields

Each event or span creation has the fields and message directly provided as well as some metadata about where it was called from. This data is mapped to Modality trace data as follows:

Metadata

• message or name -> event.name
• level -> event.severity
• module_path -> event.source.module
• file -> event.source.file
• line -> event.source.line
• the kind of event -> event.internal.rs.kind ["span:defined", "span:enter", "span:exit" ]
• id -> event.internal.rs.span_id

Fields

All fields are mapped directly as is to event.*, excect fields prefixed with modality. which are mapped to the datasource specific namespace event.internal.rs.*. Fields manually set will overwrite any any default values set by metadata, if present.

License

Copyright 2022 Auxon Corporation

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.