Adds test for remote datacenter selection and query logic.

This commit is contained in:
James Phillips 2015-11-10 21:16:04 -08:00
parent bbc5185000
commit d06e2a535d
2 changed files with 384 additions and 5 deletions

View File

@ -305,7 +305,7 @@ func (p *PreparedQuery) Execute(args *structs.PreparedQueryExecuteRequest,
// by the query setup.
if len(reply.Nodes) == 0 {
wrapper := &queryServerWrapper{p.srv}
if err := queryFailover(wrapper, query, args, reply); err != nil {
if err := queryFailover(wrapper, query, args.Limit, args.QueryOptions, reply); err != nil {
return err
}
}
@ -488,7 +488,7 @@ func (q *queryServerWrapper) ForwardDC(method, dc string, args interface{}, repl
// queryFailover runs an algorithm to determine which DCs to try and then calls
// them to try to locate alternative services.
func queryFailover(q queryServer, query *structs.PreparedQuery,
args *structs.PreparedQueryExecuteRequest,
limit int, options structs.QueryOptions,
reply *structs.PreparedQueryExecuteResponse) error {
// Pull the list of other DCs. This is sorted by RTT in case the user
@ -543,10 +543,10 @@ func queryFailover(q queryServer, query *structs.PreparedQuery,
remote := &structs.PreparedQueryExecuteRemoteRequest{
Datacenter: dc,
Query: *query,
Limit: args.Limit,
QueryOptions: args.QueryOptions,
Limit: limit,
QueryOptions: options,
}
if err := q.ForwardDC("PreparedQuery.ExecuteRemote", dc, &remote, &reply); err != nil {
if err := q.ForwardDC("PreparedQuery.ExecuteRemote", dc, remote, reply); err != nil {
q.GetLogger().Printf("[WARN] consul.prepared_query: Failed querying for service '%s' in datacenter '%s': %s", query.Service.Service, dc, err)
continue
}

View File

@ -1,7 +1,9 @@
package consul
import (
"bytes"
"fmt"
"log"
"net/rpc"
"os"
"reflect"
@ -1800,3 +1802,380 @@ func TestPreparedQuery_Wrapper(t *testing.T) {
t.Fatalf("err: %v", err)
}
}
type mockQueryServer struct {
Datacenters []string
DatacentersError error
QueryLog []string
QueryFn func(dc string, args interface{}, reply interface{}) error
Logger *log.Logger
LogBuffer *bytes.Buffer
}
func (m *mockQueryServer) JoinQueryLog() string {
return strings.Join(m.QueryLog, "|")
}
func (m *mockQueryServer) GetLogger() *log.Logger {
if m.Logger == nil {
m.LogBuffer = new(bytes.Buffer)
m.Logger = log.New(m.LogBuffer, "", 0)
}
return m.Logger
}
func (m *mockQueryServer) GetOtherDatacentersByDistance() ([]string, error) {
return m.Datacenters, m.DatacentersError
}
func (m *mockQueryServer) ForwardDC(method, dc string, args interface{}, reply interface{}) error {
m.QueryLog = append(m.QueryLog, fmt.Sprintf("%s:%s", dc, method))
if ret, ok := reply.(*structs.PreparedQueryExecuteResponse); ok {
ret.Datacenter = dc
}
if m.QueryFn != nil {
return m.QueryFn(dc, args, reply)
} else {
return nil
}
}
func TestPreparedQuery_queryFailover(t *testing.T) {
query := &structs.PreparedQuery{
Service: structs.ServiceQuery{
Failover: structs.QueryDatacenterOptions{
NearestN: 0,
Datacenters: []string{""},
},
},
}
nodes := func() structs.CheckServiceNodes {
return structs.CheckServiceNodes{
structs.CheckServiceNode{
Node: &structs.Node{Node: "node1"},
},
structs.CheckServiceNode{
Node: &structs.Node{Node: "node2"},
},
structs.CheckServiceNode{
Node: &structs.Node{Node: "node3"},
},
}
}
// Datacenters are available but the query doesn't use them.
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 0 || reply.Datacenter != "" || reply.Failovers != 0 {
t.Fatalf("bad: %v", reply)
}
}
// Make it fail to get datacenters.
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
DatacentersError: fmt.Errorf("XXX"),
}
var reply structs.PreparedQueryExecuteResponse
err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply)
if err == nil || !strings.Contains(err.Error(), "XXX") {
t.Fatalf("bad: %v", err)
}
if len(reply.Nodes) != 0 || reply.Datacenter != "" || reply.Failovers != 0 {
t.Fatalf("bad: %v", reply)
}
}
// The query wants to use other datacenters but none are available.
query.Service.Failover.NearestN = 3
{
mock := &mockQueryServer{
Datacenters: []string{},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 0 || reply.Datacenter != "" || reply.Failovers != 0 {
t.Fatalf("bad: %v", reply)
}
}
// Try the first three nearest datacenters, first one has the data.
query.Service.Failover.NearestN = 3
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "dc1" {
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "dc1" || reply.Failovers != 1 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc1:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
}
// Try the first three nearest datacenters, last one has the data.
query.Service.Failover.NearestN = 3
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "dc3" {
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "dc3" || reply.Failovers != 3 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc1:PreparedQuery.ExecuteRemote|dc2:PreparedQuery.ExecuteRemote|dc3:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
}
// Try the first four nearest datacenters, nobody has the data.
query.Service.Failover.NearestN = 4
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 0 ||
reply.Datacenter != "xxx" || reply.Failovers != 4 {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc1:PreparedQuery.ExecuteRemote|dc2:PreparedQuery.ExecuteRemote|dc3:PreparedQuery.ExecuteRemote|xxx:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
}
// Try the first two nearest datacenters, plus a user-specified one that
// has the data.
query.Service.Failover.NearestN = 2
query.Service.Failover.Datacenters = []string{"dc4"}
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "dc4" {
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "dc4" || reply.Failovers != 3 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc1:PreparedQuery.ExecuteRemote|dc2:PreparedQuery.ExecuteRemote|dc4:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
}
// Add in a hard-coded value that overlaps with the nearest list.
query.Service.Failover.NearestN = 2
query.Service.Failover.Datacenters = []string{"dc4", "dc1"}
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "dc4" {
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "dc4" || reply.Failovers != 3 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc1:PreparedQuery.ExecuteRemote|dc2:PreparedQuery.ExecuteRemote|dc4:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
}
// Now add a bogus user-defined one to the mix.
query.Service.Failover.NearestN = 2
query.Service.Failover.Datacenters = []string{"nope", "dc4", "dc1"}
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "dc4" {
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "dc4" || reply.Failovers != 3 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc1:PreparedQuery.ExecuteRemote|dc2:PreparedQuery.ExecuteRemote|dc4:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
if !strings.Contains(mock.LogBuffer.String(), "Skipping unknown datacenter") {
t.Fatalf("bad: %s", mock.LogBuffer.String())
}
}
// Same setup as before but dc1 is going to return an error and should
// get skipped over, still yielding data from dc4 which comes later.
query.Service.Failover.NearestN = 2
query.Service.Failover.Datacenters = []string{"dc4", "dc1"}
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "dc1" {
return fmt.Errorf("XXX")
} else if dc == "dc4" {
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "dc4" || reply.Failovers != 3 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc1:PreparedQuery.ExecuteRemote|dc2:PreparedQuery.ExecuteRemote|dc4:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
if !strings.Contains(mock.LogBuffer.String(), "Failed querying") {
t.Fatalf("bad: %s", mock.LogBuffer.String())
}
}
// Just use a hard-coded list and now xxx has the data.
query.Service.Failover.NearestN = 0
query.Service.Failover.Datacenters = []string{"dc3", "xxx"}
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "xxx" {
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 0, structs.QueryOptions{}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "xxx" || reply.Failovers != 2 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "dc3:PreparedQuery.ExecuteRemote|xxx:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
}
// Make sure the limit and query options are plumbed through.
query.Service.Failover.NearestN = 0
query.Service.Failover.Datacenters = []string{"xxx"}
{
mock := &mockQueryServer{
Datacenters: []string{"dc1", "dc2", "dc3", "xxx", "dc4"},
QueryFn: func(dc string, args interface{}, reply interface{}) error {
inp := args.(*structs.PreparedQueryExecuteRemoteRequest)
ret := reply.(*structs.PreparedQueryExecuteResponse)
if dc == "xxx" {
if inp.Limit != 5 {
t.Fatalf("bad: %d", inp.Limit)
}
if inp.RequireConsistent != true {
t.Fatalf("bad: %v", inp.RequireConsistent)
}
ret.Nodes = nodes()
}
return nil
},
}
var reply structs.PreparedQueryExecuteResponse
if err := queryFailover(mock, query, 5, structs.QueryOptions{RequireConsistent: true}, &reply); err != nil {
t.Fatalf("err: %v", err)
}
if len(reply.Nodes) != 3 ||
reply.Datacenter != "xxx" || reply.Failovers != 1 ||
!reflect.DeepEqual(reply.Nodes, nodes()) {
t.Fatalf("bad: %v", reply)
}
if queries := mock.JoinQueryLog(); queries != "xxx:PreparedQuery.ExecuteRemote" {
t.Fatalf("bad: %s", queries)
}
}
}