// RTTResolver returns a Sliver from a Site with lowest RTT given a client's IP.
func RTTResolver(c appengine.Context, toolID string, ip net.IP) (net.IP, error) {
cgIP := rtt.GetClientGroup(ip).IP
rttKey := datastore.NewKey(c, "string", "rtt", 0, nil)
key := datastore.NewKey(c, "ClientGroup", cgIP.String(), 0, rttKey)
// Get ClientGroup from datastore.
var cg rtt.ClientGroup
err := data.GetData(c, MCKey_ClientGroup(cgIP), key, &cg)
if err != nil {
if err == datastore.ErrNoSuchEntity {
return nil, ErrNotEnoughData
}
return nil, err
}
// Get first error-less Site and a random SliverTool from selected Site.
var siteID string
var sliverTool *data.SliverTool
for _, sr := range cg.SiteRTTs {
siteID = sr.SiteID
sliverTool, err = data.GetRandomSliverFromSite(c, toolID, siteID)
if err == nil {
return net.ParseIP(sliverTool.SliverIPv4), nil
}
}
// No valid Site found.
return nil, ErrNotEnoughData
}
// GetLastSuccesfulImportDate returns the last recorded time of a successful
// bigquery import.
func GetLastSuccesfulImportDate(c appengine.Context) (time.Time, error) {
key := datastore.NewKey(c, "Stats", DSKeyStats, 0, DatastoreParentKey(c))
var s Stats
err := data.GetData(c, DSKeyStats, key, &s)
if err == datastore.ErrNoSuchEntity {
return EarliestTimewithRTTData, nil
} else if err != nil {
return s.LastSuccessfulImportDate, err
}
return s.LastSuccessfulImportDate, nil
}
// SetLastSuccesfulImportDate sets a time as the last recorded time of a
// successful bigquery import.
func SetLastSuccessfulImportDate(c appengine.Context, t time.Time) error {
key := datastore.NewKey(c, "Stats", DSKeyStats, 0, DatastoreParentKey(c))
var s Stats
if err := data.GetData(c, DSKeyStats, key, &s); err != datastore.ErrNoSuchEntity && err != nil {
return err
}
s.LastSuccessfulImportDate = t
if err := data.SetData(c, DSKeyStats, key, &s); err != nil {
return err
}
return nil
}