func()

in cli_tools/common/image/importer/inflater.go [209:283]
62 lines of code
13 McCabe index (conditional complexity)

func (facade *shadowTestInflaterFacade) Inflate() (persistentDisk, inflationInfo, error) {
	inflaterChan := make(chan string)

	// Launch main inflater.
	var pd persistentDisk
	var ii inflationInfo
	var err error
	go func() {
		pd, ii, err = facade.mainInflater.Inflate()
		if err != nil {
			inflaterChan <- sigMainInflaterErr
		} else {
			inflaterChan <- sigMainInflaterDone
		}
	}()

	// Launch shadow inflater.
	var shadowPd persistentDisk
	var shadowIi inflationInfo
	var shadowErr error
	go func() {
		shadowPd, shadowIi, shadowErr = facade.shadowInflater.Inflate()
		if shadowErr != nil {
			inflaterChan <- sigShadowInflaterErr
		} else {
			inflaterChan <- sigShadowInflaterDone
		}
	}()

	var matchResult string

	// Return early if main inflater finished first.
	result := <-inflaterChan
	if result == sigMainInflaterDone || result == sigMainInflaterErr {
		if result == sigMainInflaterDone {
			matchResult = "Main inflater finished earlier"
		} else {
			matchResult = "Main inflater failed earlier"
		}

		// Wait for shadowInflater.inflate() to be canceled. Otherwise, shadowInflater.inflate() may
		// be interrupted with temporary resources left: b/169073057
		cancelResult := facade.shadowInflater.Cancel("cleanup shadow PD")
		if cancelResult == false {
			matchResult += " cleanup failed"
		}
		return pd, ii, err
	}

	// Wait for main inflater to finish, then process shadow inflater's result.
	mainResult := <-inflaterChan
	if result == sigShadowInflaterDone {
		if mainResult == sigMainInflaterErr {
			matchResult = "Main inflater failed while shadow inflater succeeded"
		} else {
			matchResult = facade.compareWithShadowInflater(&pd, &shadowPd, &ii, &shadowIi)
		}
	} else if result == sigShadowInflaterErr && mainResult == sigMainInflaterDone {
		if isCausedByUnsupportedFormat(shadowErr) {
			matchResult = "Shadow inflater doesn't support the format while main inflater supports"
		} else if isCausedByAlphaAPIAccess(shadowErr) {
			matchResult = "Shadow inflater not executed: no Alpha API access"
		} else {
			matchResult = fmt.Sprintf("Shadow inflater failed while main inflater succeeded: [%v]", shadowErr)
		}
	}

	facade.logger.Metric(&pb.OutputInfo{
		ShadowDiskMatchResult: matchResult,
		InflationType:         ii.inflationType,
		InflationTimeMs:       []int64{ii.inflationTime.Milliseconds()},
		ShadowInflationTimeMs: []int64{shadowIi.inflationTime.Milliseconds()},
	})
	return pd, ii, err
}