github.com/letsencrypt/trillian@v1.1.2-0.20180615153820-ae375a99d36a/util/etcd/election_test.go (about)

     1  // Copyright 2018 Google Inc. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package etcd
    16  
    17  import (
    18  	"context"
    19  	"sync"
    20  	"testing"
    21  	"time"
    22  
    23  	"github.com/coreos/etcd/clientv3"
    24  	"github.com/google/trillian/testonly/integration/etcd"
    25  	"github.com/google/trillian/util/election"
    26  )
    27  
    28  func TestMasterElectionThroughCommonClient(t *testing.T) {
    29  	_, client, cleanup, err := etcd.StartEtcd()
    30  	if err != nil {
    31  		t.Fatalf("StartEtcd(): %v", err)
    32  	}
    33  	defer cleanup()
    34  
    35  	ctx := context.Background()
    36  	fact := NewElectionFactory("serv", client, "trees/")
    37  
    38  	el1, err := fact.NewElection(ctx, 10)
    39  	if err != nil {
    40  		t.Fatalf("NewElection(10): %v", err)
    41  	}
    42  	el2, err := fact.NewElection(ctx, 20)
    43  	if err != nil {
    44  		t.Fatalf("NewElection(20): %v", err)
    45  	}
    46  
    47  	if err := el1.WaitForMastership(ctx); err != nil {
    48  		t.Fatalf("WaitForMastership(10): %v", err)
    49  	}
    50  	if err := el2.WaitForMastership(ctx); err != nil {
    51  		t.Fatalf("WaitForMastership(20): %v", err)
    52  	}
    53  
    54  	if err := el1.Close(ctx); err != nil {
    55  		t.Fatalf("Close(10): %v", err)
    56  	}
    57  	if err := el2.Close(ctx); err != nil {
    58  		t.Fatalf("Close(20): %v", err)
    59  	}
    60  }
    61  
    62  func everyoneAgreesOnMaster(ctx context.Context, t *testing.T, want string, elections []election.MasterElection) {
    63  	t.Helper()
    64  	for _, e := range elections {
    65  		for {
    66  			got, err := e.GetCurrentMaster(ctx)
    67  			if err == election.ErrNoMaster {
    68  				t.Error("No leader...")
    69  				time.Sleep(time.Second)
    70  				continue
    71  			} else if err != nil {
    72  				t.Fatalf("Failed to GetCurrentMaster: %v", err)
    73  			}
    74  			if got != want {
    75  				t.Errorf("Current master is %v, want %v", got, want)
    76  			}
    77  			break
    78  		}
    79  	}
    80  }
    81  
    82  func mustCreateClientFor(t *testing.T, e string) *clientv3.Client {
    83  	t.Helper()
    84  	c, err := clientv3.New(clientv3.Config{
    85  		Endpoints: []string{e},
    86  	})
    87  	if err != nil {
    88  		t.Fatalf("Error creating etcd client: %v", err)
    89  	}
    90  	return c
    91  }
    92  
    93  func TestGetCurrentMaster(t *testing.T) {
    94  	e, client, cleanup, err := etcd.StartEtcd()
    95  	if err != nil {
    96  		t.Fatalf("StartEtcd(): %v", err)
    97  	}
    98  	defer cleanup()
    99  	// add another active participant
   100  	client2 := mustCreateClientFor(t, e.Config().LCUrls[0].String())
   101  	defer client2.Close()
   102  
   103  	// add a couple of passive observers
   104  	ob1 := mustCreateClientFor(t, e.Config().LCUrls[0].String())
   105  	defer ob1.Close()
   106  	ob2 := mustCreateClientFor(t, e.Config().LCUrls[0].String())
   107  	defer ob2.Close()
   108  
   109  	ctx := context.Background()
   110  	pfx := "trees/"
   111  	facts := []*ElectionFactory{
   112  		NewElectionFactory("serv1", client, pfx),
   113  		NewElectionFactory("serv2", client2, pfx),
   114  		NewElectionFactory("ob1", ob1, pfx),
   115  		NewElectionFactory("ob2", ob2, pfx),
   116  	}
   117  
   118  	elections := make([]election.MasterElection, 0)
   119  	for _, f := range facts {
   120  		e, err := f.NewElection(ctx, 10)
   121  		if err != nil {
   122  			t.Fatalf("NewElection(10): %v", err)
   123  		}
   124  		elections = append(elections, e)
   125  	}
   126  
   127  	wg := &sync.WaitGroup{}
   128  	for _, e := range elections[0:2] {
   129  		wg.Add(1)
   130  		go func(e election.MasterElection) {
   131  			if err := e.WaitForMastership(ctx); err != nil {
   132  				t.Errorf("WaitForMastership(10): %v", err)
   133  			}
   134  			id := e.(*MasterElection).instanceID
   135  
   136  			everyoneAgreesOnMaster(ctx, t, id, elections)
   137  			if err := e.Close(ctx); err != nil {
   138  				t.Errorf("Close(10): %v", err)
   139  			}
   140  			wg.Done()
   141  		}(e)
   142  	}
   143  	wg.Wait()
   144  }
   145  
   146  func TestGetCurrentMasterReturnsNoLeader(t *testing.T) {
   147  	ctx := context.Background()
   148  	_, client, cleanup, err := etcd.StartEtcd()
   149  	if err != nil {
   150  		t.Fatalf("StartEtcd(): %v", err)
   151  	}
   152  	defer cleanup()
   153  	fact := NewElectionFactory("serv1", client, "trees/")
   154  	el, err := fact.NewElection(ctx, 10)
   155  	if err != nil {
   156  		t.Fatalf("NewElection(10): %v", err)
   157  	}
   158  	if err := el.WaitForMastership(ctx); err != nil {
   159  		t.Errorf("WaitForMastership(10): %v", err)
   160  	}
   161  	if err := el.Close(ctx); err != nil {
   162  		t.Errorf("Close(10): %v", err)
   163  	}
   164  	_, err = el.GetCurrentMaster(ctx)
   165  	if want := election.ErrNoMaster; err != want {
   166  		t.Errorf("GetCurrentMaster()=%v, want %v", err, want)
   167  	}
   168  }