func (s *SteadyState) populateApps(resp *models.SteadyStateResponse) error {
req := resp.Request
resp.Apps = make([]models.App, req.NumApps)
var err error
totalInstances := 0
for i, _ := range resp.Apps {
resp.Apps[i].Id = i
resp.Apps[i].Size, err = s.AppSizeDistribution.Sample(float64(req.MeanInstancesPerApp))
if err != nil {
return fmt.Errorf("sampling app size: %s", err)
}
totalInstances += resp.Apps[i].Size
}
resp.TotalInstances = totalInstances
return nil
}
func (s *SteadyState) Execute(logger lager.Logger, req models.SteadyStateRequest) (*models.SteadyStateResponse, error) {
logger.Info("start", lager.Data{"input": req})
defer logger.Info("done")
var resp models.SteadyStateResponse
resp.Request = req
totalInstances := float64(req.NumApps) * float64(req.MeanInstancesPerApp)
resp.MeanInstancesPerHost = totalInstances / float64(req.NumHosts)
if err := s.populateApps(&resp); err != nil {
return nil, err
}
if err := s.populateInstances(&resp); err != nil {
return nil, err
}
logger.Info("success")
return &resp, nil
}
func (s *SteadyState) populateInstances(resp *models.SteadyStateResponse) error {
req := resp.Request
resp.Instances = make([]models.Instance, resp.TotalInstances)
appId := 0
appInstanceCounter := 0
for i := 0; i < resp.TotalInstances; i++ {
resp.Instances[i].Id = i
if appInstanceCounter >= resp.Apps[appId].Size {
appId++
appInstanceCounter = 0
}
appInstanceCounter++
resp.Instances[i].AppId = appId
resp.Instances[i].HostId = i % req.NumHosts
}
return nil
}