elect/elect_test.go

package elect_test

import (
	"testing"
	"time"

	"github.com/stretchr/testify/require"
)

func TestOne(t *testing.T) {
	t.Parallel()

	ts := NewTestSystem(t, 1)
	defer ts.Stop()

	require.False(t, ts.Candidate(0).IsLeader())

	require.Eventually(t, ts.Candidate(0).IsLeader, 20*time.Second, 100*time.Millisecond)
}

func TestThree(t *testing.T) {
	t.Parallel()

	ts := NewTestSystem(t, 3)
	defer ts.Stop()

	require.False(t, ts.Candidate(0).IsLeader())
	require.False(t, ts.Candidate(1).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())

	require.Eventually(t, ts.Candidate(0).IsLeader, 20*time.Second, 100*time.Millisecond)
	require.False(t, ts.Candidate(1).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())
}

func TestFailover(t *testing.T) {
	t.Parallel()

	ts := NewTestSystem(t, 3)
	defer ts.Stop()

	require.False(t, ts.Candidate(0).IsLeader())
	require.False(t, ts.Candidate(1).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())

	require.Eventually(t, ts.Candidate(0).IsLeader, 20*time.Second, 100*time.Millisecond)
	require.False(t, ts.Candidate(1).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())

	ts.SetServer(1)

	require.Eventually(t, func() bool { return !ts.Candidate(0).IsLeader() }, 15*time.Second, 100*time.Millisecond)

	// New candidate must not get leadership before old candidate loses it
	require.False(t, ts.Candidate(1).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())

	require.Eventually(t, ts.Candidate(1).IsLeader, 20*time.Second, 100*time.Millisecond)
	require.False(t, ts.Candidate(0).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())
}

func TestPartialVotes(t *testing.T) {
	t.Parallel()

	ts := NewTestSystem(t, 3)
	defer ts.Stop()

	ts.Voter(0).Stop()

	require.False(t, ts.Candidate(0).IsLeader())
	require.False(t, ts.Candidate(1).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())

	require.Eventually(t, ts.Candidate(0).IsLeader, 20*time.Second, 100*time.Millisecond)
	require.False(t, ts.Candidate(1).IsLeader())
	require.False(t, ts.Candidate(2).IsLeader())
}