func BuildResourceCircuitBreaker()

in core/circuitbreaker/rule_manager.go [404:447]
37 lines of code
9 McCabe index (conditional complexity)

func BuildResourceCircuitBreaker(res string, rulesOfRes []*Rule, oldResCbs []CircuitBreaker) []CircuitBreaker {
	newCbsOfRes := make([]CircuitBreaker, 0, len(rulesOfRes))
	for _, r := range rulesOfRes {
		if res != r.Resource {
			logging.Error(errors.Errorf("unmatched resource name expect: %s, actual: %s", res, r.Resource), "Unmatched resource name in circuitBreaker.BuildResourceCircuitBreaker()", "rule", r)
			continue
		}
		equalIdx, reuseStatIdx := calculateReuseIndexFor(r, oldResCbs)

		// First check equals scenario
		if equalIdx >= 0 {
			// reuse the old cb
			equalOldCb := oldResCbs[equalIdx]
			newCbsOfRes = append(newCbsOfRes, equalOldCb)
			// remove old cb from oldResCbs
			oldResCbs = append(oldResCbs[:equalIdx], oldResCbs[equalIdx+1:]...)
			continue
		}

		generator := cbGenFuncMap[r.Strategy]
		if generator == nil {
			logging.Warn("[CircuitBreaker BuildResourceCircuitBreaker] Ignoring the rule due to unsupported circuit breaking strategy", "rule", r)
			continue
		}

		var cb CircuitBreaker
		var e error
		if reuseStatIdx >= 0 {
			cb, e = generator(r, oldResCbs[reuseStatIdx].BoundStat())
		} else {
			cb, e = generator(r, nil)
		}
		if cb == nil || e != nil {
			logging.Warn("[CircuitBreaker BuildResourceCircuitBreaker] Ignoring the rule due to bad generated circuit breaker", "rule", r, "err", e.Error())
			continue
		}

		if reuseStatIdx >= 0 {
			oldResCbs = append(oldResCbs[:reuseStatIdx], oldResCbs[reuseStatIdx+1:]...)
		}
		newCbsOfRes = append(newCbsOfRes, cb)
	}
	return newCbsOfRes
}