Add builtins tracing for ds calls

[carabasdaniel]

No description provided.

[coveralls]

Pull Request Test Coverage Report for Build 4557094471

• 30 of 62 (48.39%) changed or added relevant lines in 8 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.2%) to 38.524%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
builtins/edge/ds/graph.go	0	1	0.0%
builtins/edge/ds/identity.go	0	1	0.0%
builtins/edge/ds/object.go	0	1	0.0%
builtins/edge/ds/relation.go	0	1	0.0%
builtins/edge/ds/user.go	0	1	0.0%
builtins/edge/ds/check.go	0	2	0.0%
builtins/edge/ds/helper.go	0	8	0.0%
pkg/testing/assets.go	30	47	63.83%

Files with Coverage Reduction	New Missed Lines	%
builtins/edge/ds/identity.go	1	60.0%

Totals
Change from base Build 4369546645:	0.2%
Covered Lines:	1180
Relevant Lines:	3063

---

💛 - Coveralls

[gertd]

I suggest we extract the trace logic and use the fnName passed in for each built-in to make it reusable. Now that we have a mechanism we might want to explore if there is anything we want to trace for the argument parsing.

[gertd]

Can we extract this in to helper.go as

func traceError(bctx topdown.BuiltinContext, fnName string, err error) {
	if bctx.TraceEnabled {
		if len(bctx.QueryTracers) > 0 {
			bctx.QueryTracers[0].TraceEvent(topdown.Event{
				Op:      topdown.FailOp,
				Message: fmt.Sprintf("%s error:%s", fnName, err.Error()),
			})
		}
	}
}

This will make it reusable and leverage the function name as used in the code at all times.

[gertd]

Line 175 there is no trace added for the CheckPermission call

[carabasdaniel]

LGTM