Wrappergen

Warning Very WIP, no tests, no guarantees.

Code-gen to add tracing, timing wrappers and constructors.

Timing and tracing code is very common boilerplate scattered around entire codebases. Wrappergen aims make use of codegen to remove that boilerplate.

Example

This repo contains ./example/example.go which looks like so:

package example

import (
	"context"
)

type Example interface {
	Test(context.Context, int64) uint8
}

type example struct {
	attribute string
}

func (e *example) Test(ctx context.Context, i int64) uint8 {
	return 5
}

Timing

$ wrappergen timing --indir ./example/ --interface Example

// Code generated by wrappergen v0.0.1. DO NOT EDIT.
package example

import i0 "github.com/hfaulds/wrappergen/timing"
import i1 "context"

func NewExampleTimer(p0 Example, p1 i0.Timing) Example {
	return timeExample{
		wrapped: p0,
		timing:  p1,
	}
}

type timeExample struct {
	wrapped Example
	timing  i0.Timing
}

func (t timeExample) Test(p0 i1.Context, p1 int64) uint8 {
	timer := t.timing.Timer()
	defer timer.End(ctx, "Test")
	return t.wrapped.Test(p0, p1)
}

Tracing

$ wrappergen tracing --indir ./example/ --interface Example

// Code generated by wrappergen v0.0.1. DO NOT EDIT.
package example

import i0 "github.com/hfaulds/wrappergen/tracing"
import i1 "context"

func NewExampleTracer(p0 Example, p1 i0.Tracing) Example {
	return traceExample{
		wrapped: p0,
		trace:   p1,
	}
}

type traceExample struct {
	wrapped Example
	trace   i0.Tracing
}

func (t traceExample) Test(p0 i1.Context, p1 int64) uint8 {
	ctx, span := t.trace.ChildSpan(p0, "Test")
	defer span.Finish()
	return t.wrapped.Test(ctx, p1)
}

Constructor

$ wrappergen constructor --indir ./example/ --interface Example --struct example --timing --tracing

// Code generated by wrappergen v0.0.1. DO NOT EDIT.
package example

import i0 "github.com/hfaulds/wrappergen/tracing"
import i1 "github.com/hfaulds/wrappergen/timing"

func NewExample(p0 string, p1 i0.Tracing, p2 i1.Timing) Example {
	return NewExampleTracer(
		NewExampleTimer(
			example{
				attribute: p0,
			},
			p1,
		),
		p2,
	)
}

TODO

• Testing
• CI
• Tidy up code generation