Generates interface decorators with opentracing support.
go get github.com/gojuno/tracegen
type Cache interface {
Set(ctx context.Context, key, value []byte) error
Get(ctx context.Context, key []byte) (value []byte, err error)
}tracegen -i Cache -o example/cache_trace.go example
Will generate:
type CacheTracer struct {
next Cache
prefix string
}
func NewCacheTracer(next Cache, prefix string) *CacheTracer {
return &CacheTracer{
next: next,
prefix: prefix,
}
}
func (t *CacheTracer) Get(in context.Context, in1 []byte) (out []byte, out1 error) {
span, in := opentracing.StartSpanFromContext(in, t.prefix+".Cache.Get")
defer func() {
if out1 != nil {
ext.Error.Set(span, true)
span.LogFields(
log.String("event", "error"),
log.String("message", out1.Error()),
)
}
span.Finish()
}()
return t.next.Get(in, in1)
}
func (t *CacheTracer) Set(in context.Context, in1 []byte, in2 []byte) (out error) {
span, in := opentracing.StartSpanFromContext(in, t.prefix+".Cache.Set")
defer func() {
if out != nil {
ext.Error.Set(span, true)
span.LogFields(
log.String("event", "error"),
log.String("message", out.Error()),
)
}
span.Finish()
}()
return t.next.Set(in, in1, in2)
}