feat: Add integration for github.com/astaxie/beego

[reggiemcdonald]

github.com/astaxie/beego Integration

Description

This PR provides beego instrumentation.

Implementation

This integration makes use of the net/http integration to provide tracing to HTTP requests.

HTTP requests to the beego app running this middleware will be traced.

The following options are provided:

• WithTracer(trace.Tracer)
• WithMeter(metric.Meter)
• WithPropagators(propagation.Propagators)
• WithFilter(Filter)
• WithSpanNameFormatter(Formatter)

which allows users to specify the tracer, meter and propagators to be used. In accordance with the semantic conventions, span names are generated from the path of the HTTP request by default. Users are able to override this behaviour with the provided WithSpanNameFormatter option.
WithFilter allows users to filter out which requests should be traced.

Additionally, Beego supports HTML template rendering using calls to beego.Controller.Render. This instrumentation provides a wrapper function to add a child span to the rendering of the template files.

A dockerized example can be found here. In an effort to keep this PR shorter, I've decided to move the example to a separate PR, which I'll open once this gets merged.

TODO

• Additional testing
• Tracing render

Addresses: #82

/cc @nlehrer @danherr

[jmacd]

💯

[MrAlias]

The approach looks good, especially the testing, well done. Had some minor comments/suggestions around naming and docs.

[Aneurysm9]

@reggiemcdonald can you add a CHANGELOG.md entry for this? I think this is otherwise ready to merge.