xring_test.go

package xring

import (
	"testing"
)

func TestGet(t *testing.T) {
	nodes := []string{"a", "b", "c"}
	cnf := &Config{
		VirtualNodes: 0,
		LoadFactor:   1,
	}
	hashRing := NewRing(nodes, cnf)

	expectNodesABC(t, hashRing)
}

func expectNodesABC(t *testing.T, hashRing *Ring) {
	// Python hash_ring module test case
	expectNode(t, hashRing, "test", "a")
	expectNode(t, hashRing, "test", "a")
	expectNode(t, hashRing, "test1", "c")
	expectNode(t, hashRing, "test2", "c")
	expectNode(t, hashRing, "test3", "c")
	expectNode(t, hashRing, "test4", "c")
	expectNode(t, hashRing, "test5", "b")
	expectNode(t, hashRing, "aaaa", "c")
	expectNode(t, hashRing, "bbbb", "a")
}

func expectNode(t *testing.T, hashRing *Ring, key string, expected string) {
	node, err := hashRing.Get(key)
	if err != nil || node != expected {
		t.Error("GetNode(", key, ") expected", expected, "but got", node, err)
	}
	hashRing.Done(node)
}

func failNode(t *testing.T, hashRing *Ring, key string, expected string, expectedErr error) {
	node, err := hashRing.Get(key)
	if err != expectedErr || node != expected {
		t.Error("GetNode(", key, ") expected", expected, "but got", node, err)
	}
}

func TestHeavyLoad(t *testing.T) {
	nodes := []string{"a", "b", "c"}
	cnf := &Config{
		VirtualNodes: 0,
		LoadFactor:   1,
	}
	hashRing := NewRing(nodes, cnf)
	failNode(t, hashRing, "test", "a", nil)
	failNode(t, hashRing, "test", "b", nil)
	failNode(t, hashRing, "test", "c", nil)
	failNode(t, hashRing, "test", "", ERR_HEAVY_LOAD)

}

func TestDistribution(t *testing.T) {
	nodes := []string{"a", "b", "c"}
	cnf := &Config{
		VirtualNodes: 0,
		LoadFactor:   1,
	}
	hashRing := NewRing(nodes, cnf)
	failNode(t, hashRing, "test", "a", nil)
	failNode(t, hashRing, "test", "b", nil)
	failNode(t, hashRing, "test", "c", nil)

}