func SetServers(svcId string, servers []core.Server) error {
// in case of failure
oldService, err := database.GetService(svcId)
if err != nil {
return err
}
oldServers := oldService.Servers
// implement in balancer
err = balance.SetServers(svcId, servers)
if err != nil {
return err
}
if !database.CentralStore {
// add to backend
err = database.SetServers(svcId, servers)
if err != nil {
// undo balance action
if uerr := balance.SetServers(svcId, oldServers); uerr != nil {
err = fmt.Errorf("%v - %v", err.Error(), uerr.Error())
}
return err
}
}
return nil
}
func (n None) SetServers(svcId string, servers []core.Server) error {
err := common.SetServers(svcId, servers)
if err != nil {
return err
}
if database.CentralStore {
return database.SetServers(svcId, servers)
}
return nil
}
// SetServers tells all members to replace a service's servers with a new set.
// rolls back on failure
func (r *Redis) SetServers(svcId string, servers []core.Server) error {
conn := pool.Get()
defer conn.Close()
service, err := common.GetService(svcId)
if err != nil {
return NoServiceError
}
oldServers := service.Servers
// publishStringJson to others
err = r.publishStringJson(conn, "set-servers", svcId, servers)
if err != nil {
return err
}
actionHash := fmt.Sprintf("%x", md5.Sum([]byte(fmt.Sprintf("set-servers %s %s", servers, svcId))))
// ensure all members applied action
err = r.waitForMembers(conn, actionHash)
if err != nil {
uActionHash := fmt.Sprintf("%x", md5.Sum([]byte(fmt.Sprintf("set-servers %s %s", oldServers, svcId))))
// cleanup rollback cruft. clear actionHash ensures no mistakes on re-submit
defer conn.Do("DEL", uActionHash, actionHash)
// attempt rollback - no need to waitForMembers here
uerr := r.publishStringJson(conn, "set-servers", svcId, oldServers)
if uerr != nil {
err = fmt.Errorf("%v - %v", err, uerr)
}
return err
}
if database.CentralStore {
return database.SetServers(svcId, servers)
}
return nil
}
func TestSetServers(t *testing.T) {
servers := []core.Server{}
servers = append(servers, testServer2)
if err := database.SetServers(testService1.Id, servers); err != nil {
t.Errorf("Failed to SET servers - %v", err)
}
service, err := ioutil.ReadFile("/tmp/scribbleTest/services/tcp-192_168_0_15-80.json")
if err != nil {
t.Error(err)
}
svc := testService1
svc.Servers = append(svc.Servers, testServer1)
jService, err := toJson(svc)
if err != nil {
t.Error(err)
}
if string(service) == string(jService) {
t.Errorf("Failed to clear old servers on PUT")
}
}