open-nomad/client/servers/manager_test.go
2018-02-15 13:59:01 -08:00

437 lines
9.9 KiB
Go

package servers_test
import (
"fmt"
"log"
"math/rand"
"net"
"os"
"strings"
"testing"
"github.com/hashicorp/nomad/client/servers"
)
type fauxAddr struct {
Addr string
}
func (fa *fauxAddr) String() string { return fa.Addr }
func (fa *fauxAddr) Network() string { return fa.Addr }
type fauxConnPool struct {
// failPct between 0.0 and 1.0 == pct of time a Ping should fail
failPct float64
}
func (cp *fauxConnPool) Ping(net.Addr) (bool, error) {
var success bool
successProb := rand.Float64()
if successProb > cp.failPct {
success = true
}
return success, nil
}
func testManager() (m *servers.Manager) {
logger := log.New(os.Stderr, "", log.LstdFlags)
shutdownCh := make(chan struct{})
m = servers.New(logger, shutdownCh, &fauxConnPool{})
return m
}
func testManagerFailProb(failPct float64) (m *servers.Manager) {
logger := log.New(os.Stderr, "", log.LstdFlags)
shutdownCh := make(chan struct{})
m = servers.New(logger, shutdownCh, &fauxConnPool{failPct: failPct})
return m
}
func TestServers_SetServers(t *testing.T) {
m := testManager()
var num int
num = m.NumServers()
if num != 0 {
t.Fatalf("Expected zero servers to start")
}
s1 := &servers.Server{Addr: &fauxAddr{"server1"}}
s2 := &servers.Server{Addr: &fauxAddr{"server2"}}
m.SetServers([]*servers.Server{s1, s2})
num = m.NumServers()
if num != 2 {
t.Fatalf("Expected two servers")
}
all := m.GetServers()
if l := len(all); l != 2 {
t.Fatalf("expected 2 servers got %d", l)
}
if all[0] == s1 || all[0] == s2 {
t.Fatalf("expected a copy, got actual server")
}
}
// func (m *Manager) AddServer(server *metadata.Server) {
func TestServers_AddServer(t *testing.T) {
m := testManager()
var num int
num = m.NumServers()
if num != 0 {
t.Fatalf("Expected zero servers to start")
}
s1 := &servers.Server{Addr: &fauxAddr{"server1"}}
m.AddServer(s1)
num = m.NumServers()
if num != 1 {
t.Fatalf("Expected one server")
}
m.AddServer(s1)
num = m.NumServers()
if num != 1 {
t.Fatalf("Expected one server (still)")
}
s2 := &servers.Server{Addr: &fauxAddr{"server2"}}
m.AddServer(s2)
num = m.NumServers()
if num != 2 {
t.Fatalf("Expected two servers")
}
all := m.GetServers()
if l := len(all); l != 2 {
t.Fatalf("expected 2 servers got %d", l)
}
if all[0] == s1 || all[0] == s2 {
t.Fatalf("expected a copy, got actual server")
}
}
// func (m *Manager) IsOffline() bool {
func TestServers_IsOffline(t *testing.T) {
m := testManager()
if !m.IsOffline() {
t.Fatalf("bad")
}
s1 := &servers.Server{Addr: &fauxAddr{"server1"}}
m.AddServer(s1)
if m.IsOffline() {
t.Fatalf("bad")
}
m.RebalanceServers()
if m.IsOffline() {
t.Fatalf("bad")
}
m.RemoveServer(s1)
m.RebalanceServers()
if !m.IsOffline() {
t.Fatalf("bad")
}
const failPct = 0.5
m = testManagerFailProb(failPct)
m.AddServer(s1)
var on, off int
for i := 0; i < 100; i++ {
m.RebalanceServers()
if m.IsOffline() {
off++
} else {
on++
}
}
if on == 0 || off == 0 {
t.Fatalf("bad: %d %d", on, off)
}
}
func TestServers_FindServer(t *testing.T) {
m := testManager()
if m.FindServer() != nil {
t.Fatalf("Expected nil return")
}
m.AddServer(&servers.Server{Addr: &fauxAddr{"s1"}})
if m.NumServers() != 1 {
t.Fatalf("Expected one server")
}
s1 := m.FindServer()
if s1 == nil {
t.Fatalf("Expected non-nil server")
}
if s1.String() != "s1" {
t.Fatalf("Expected s1 server")
}
s1 = m.FindServer()
if s1 == nil || s1.String() != "s1" {
t.Fatalf("Expected s1 server (still)")
}
m.AddServer(&servers.Server{Addr: &fauxAddr{"s2"}})
if m.NumServers() != 2 {
t.Fatalf("Expected two servers")
}
s1 = m.FindServer()
if s1 == nil || s1.String() != "s1" {
t.Fatalf("Expected s1 server (still)")
}
m.NotifyFailedServer(s1)
s2 := m.FindServer()
if s2 == nil || s2.String() != "s2" {
t.Fatalf("Expected s2 server")
}
m.NotifyFailedServer(s2)
s1 = m.FindServer()
if s1 == nil || s1.String() != "s1" {
t.Fatalf("Expected s1 server")
}
}
func TestServers_New(t *testing.T) {
logger := log.New(os.Stderr, "", log.LstdFlags)
shutdownCh := make(chan struct{})
m := servers.New(logger, shutdownCh, &fauxConnPool{})
if m == nil {
t.Fatalf("Manager nil")
}
}
func TestServers_NotifyFailedServer(t *testing.T) {
m := testManager()
if m.NumServers() != 0 {
t.Fatalf("Expected zero servers to start")
}
s1 := &servers.Server{Addr: &fauxAddr{"s1"}}
s2 := &servers.Server{Addr: &fauxAddr{"s2"}}
// Try notifying for a server that is not managed by Manager
m.NotifyFailedServer(s1)
if m.NumServers() != 0 {
t.Fatalf("Expected zero servers to start")
}
m.AddServer(s1)
// Test again w/ a server not in the list
m.NotifyFailedServer(s2)
if m.NumServers() != 1 {
t.Fatalf("Expected one server")
}
m.AddServer(s2)
if m.NumServers() != 2 {
t.Fatalf("Expected two servers")
}
s1 = m.FindServer()
if s1 == nil || s1.String() != "s1" {
t.Fatalf("Expected s1 server")
}
m.NotifyFailedServer(s2)
s1 = m.FindServer()
if s1 == nil || s1.String() != "s1" {
t.Fatalf("Expected s1 server (still)")
}
m.NotifyFailedServer(s1)
s2 = m.FindServer()
if s2 == nil || s2.String() != "s2" {
t.Fatalf("Expected s2 server")
}
m.NotifyFailedServer(s2)
s1 = m.FindServer()
if s1 == nil || s1.String() != "s1" {
t.Fatalf("Expected s1 server")
}
}
func TestServers_NumServers(t *testing.T) {
m := testManager()
var num int
num = m.NumServers()
if num != 0 {
t.Fatalf("Expected zero servers to start")
}
s := &servers.Server{Addr: &fauxAddr{"server1"}}
m.AddServer(s)
num = m.NumServers()
if num != 1 {
t.Fatalf("Expected one server after AddServer")
}
}
func TestServers_RebalanceServers(t *testing.T) {
const failPct = 0.5
m := testManagerFailProb(failPct)
const maxServers = 100
const numShuffleTests = 100
const uniquePassRate = 0.5
// Make a huge list of nodes.
for i := 0; i < maxServers; i++ {
nodeName := fmt.Sprintf("s%02d", i)
m.AddServer(&servers.Server{Addr: &fauxAddr{nodeName}})
}
// Keep track of how many unique shuffles we get.
uniques := make(map[string]struct{}, maxServers)
for i := 0; i < numShuffleTests; i++ {
m.RebalanceServers()
var names []string
for j := 0; j < maxServers; j++ {
server := m.FindServer()
m.NotifyFailedServer(server)
names = append(names, server.String())
}
key := strings.Join(names, "|")
uniques[key] = struct{}{}
}
// We have to allow for the fact that there won't always be a unique
// shuffle each pass, so we just look for smell here without the test
// being flaky.
if len(uniques) < int(maxServers*uniquePassRate) {
t.Fatalf("unique shuffle ratio too low: %d/%d", len(uniques), maxServers)
}
}
func TestManager_RemoveServer(t *testing.T) {
const nodeNameFmt = "s%02d"
m := testManager()
if m.NumServers() != 0 {
t.Fatalf("Expected zero servers to start")
}
// Test removing server before its added
nodeName := fmt.Sprintf(nodeNameFmt, 1)
s1 := &servers.Server{Addr: &fauxAddr{nodeName}}
m.RemoveServer(s1)
m.AddServer(s1)
nodeName = fmt.Sprintf(nodeNameFmt, 2)
s2 := &servers.Server{Addr: &fauxAddr{nodeName}}
m.RemoveServer(s2)
m.AddServer(s2)
const maxServers = 19
servs := make([]*servers.Server, maxServers)
// Already added two servers above
for i := maxServers; i > 2; i-- {
nodeName := fmt.Sprintf(nodeNameFmt, i)
server := &servers.Server{Addr: &fauxAddr{nodeName}}
servs = append(servs, server)
m.AddServer(server)
}
if m.NumServers() != maxServers {
t.Fatalf("Expected %d servers, received %d", maxServers, m.NumServers())
}
m.RebalanceServers()
if m.NumServers() != maxServers {
t.Fatalf("Expected %d servers, received %d", maxServers, m.NumServers())
}
findServer := func(server *servers.Server) bool {
for i := m.NumServers(); i > 0; i-- {
s := m.FindServer()
if s == server {
return true
}
}
return false
}
expectedNumServers := maxServers
removedServers := make([]*servers.Server, 0, maxServers)
// Remove servers from the front of the list
for i := 3; i > 0; i-- {
server := m.FindServer()
if server == nil {
t.Fatalf("FindServer returned nil")
}
m.RemoveServer(server)
expectedNumServers--
if m.NumServers() != expectedNumServers {
t.Fatalf("Expected %d servers (got %d)", expectedNumServers, m.NumServers())
}
if findServer(server) {
t.Fatalf("Did not expect to find server %s after removal from the front", server.String())
}
removedServers = append(removedServers, server)
}
// Remove server from the end of the list
for i := 3; i > 0; i-- {
server := m.FindServer()
m.NotifyFailedServer(server)
m.RemoveServer(server)
expectedNumServers--
if m.NumServers() != expectedNumServers {
t.Fatalf("Expected %d servers (got %d)", expectedNumServers, m.NumServers())
}
if findServer(server) == true {
t.Fatalf("Did not expect to find server %s", server.String())
}
removedServers = append(removedServers, server)
}
// Remove server from the middle of the list
for i := 3; i > 0; i-- {
server := m.FindServer()
m.NotifyFailedServer(server)
server2 := m.FindServer()
m.NotifyFailedServer(server2) // server2 now at end of the list
m.RemoveServer(server)
expectedNumServers--
if m.NumServers() != expectedNumServers {
t.Fatalf("Expected %d servers (got %d)", expectedNumServers, m.NumServers())
}
if findServer(server) == true {
t.Fatalf("Did not expect to find server %s", server.String())
}
removedServers = append(removedServers, server)
}
if m.NumServers()+len(removedServers) != maxServers {
t.Fatalf("Expected %d+%d=%d servers", m.NumServers(), len(removedServers), maxServers)
}
// Drain the remaining servers from the middle
for i := m.NumServers(); i > 0; i-- {
server := m.FindServer()
m.NotifyFailedServer(server)
server2 := m.FindServer()
m.NotifyFailedServer(server2) // server2 now at end of the list
m.RemoveServer(server)
removedServers = append(removedServers, server)
}
if m.NumServers() != 0 {
t.Fatalf("Expected an empty server list")
}
if len(removedServers) != maxServers {
t.Fatalf("Expected all servers to be in removed server list")
}
}