Add tests for etcd v2 provider

CHANGELOG.md

@@ -3,6 +3,10 @@
 BUG FIXES:
 - Fixed go.mod and go.sum files with go mod tidy.
 
+TESTS:
+
+- Added etcd v2 provider tests.
+
 ## v2.0.1
 
 in the v2.0.0 release there was a bug that did not allow go-get. Updating to v2 requires changing the module name

providers/etcd/provider.go

@@ -10,6 +10,12 @@ import (
 	"go.etcd.io/etcd/client/v2"
 )
 
+var (
+	ErrNodesError     = fmt.Errorf("etcd nodes err")
+	ErrClusterError   = fmt.Errorf("etcd cluster err")
+	ErrInstancesError = fmt.Errorf("etcd instances err")
+)
+
 // Check that provider implements TopologyProvider interface
 var _ vshardrouter.TopologyProvider = (*Provider)(nil)
 
@@ -63,6 +69,7 @@ func mapCluster2Instances(replicasets []vshardrouter.ReplicasetInfo,
 	return currentTopology
 }
 
+// nolint:contextcheck
 func (p *Provider) GetTopology() (map[vshardrouter.ReplicasetInfo][]vshardrouter.InstanceInfo, error) {
 	resp, err := p.kapi.Get(context.TODO(), p.path, &client.GetOptions{Recursive: true})
 	if err != nil {
@@ -71,7 +78,7 @@ func (p *Provider) GetTopology() (map[vshardrouter.ReplicasetInfo][]vshardrouter
 	nodes := resp.Node.Nodes
 
 	if nodes.Len() < 2 {
-		return nil, fmt.Errorf("etcd path %s subnodes <2; minimum 2 (/clusters & /instances)", p.path)
+		return nil, fmt.Errorf("%w: etcd path %s subnodes <2; minimum 2 (/clusters & /instances)", ErrNodesError, p.path)
 	}
 
 	var replicasets []vshardrouter.ReplicasetInfo
@@ -83,7 +90,7 @@ func (p *Provider) GetTopology() (map[vshardrouter.ReplicasetInfo][]vshardrouter
 		switch filepath.Base(node.Key) {
 		case "clusters":
 			if len(node.Nodes) < 1 {
-				return nil, fmt.Errorf("etcd path %s has no clusters", node.Key)
+				return nil, fmt.Errorf("%w: etcd path %s has no clusters", ErrClusterError, node.Key)
 			}
 
 			for _, rsNode := range node.Nodes {
@@ -109,7 +116,7 @@ func (p *Provider) GetTopology() (map[vshardrouter.ReplicasetInfo][]vshardrouter
 			}
 		case "instances":
 			if len(node.Nodes) < 1 {
-				return nil, fmt.Errorf("etcd path %s has no instances", node.Key)
+				return nil, fmt.Errorf("%w: etcd path %s has no instances", ErrInstancesError, node.Key)
 			}
 
 			for _, instanceNode := range node.Nodes {

providers/etcd/provider_test.go

@@ -0,0 +1,123 @@
+package etcd
+
+import (
+	"context"
+	"errors"
+	"log"
+	"net/url"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+	"go.etcd.io/etcd/client/v2"
+	"go.etcd.io/etcd/server/v3/embed"
+)
+
+func parseEtcdUrls(strs []string) []url.URL {
+	urls := make([]url.URL, 0, len(strs))
+
+	for _, str := range strs {
+		u, err := url.Parse(str)
+		if err != nil {
+			log.Printf("Invalid url %s, error: %s", str, err.Error())
+			continue
+
+		}
+		urls = append(urls, *u)
+	}
+
+	return urls
+
+}
+
+func TestProvider_Init(t *testing.T) {
+	ctx := context.Background()
+	config := embed.NewConfig()
+
+	config.Name = "localhost"
+	config.Dir = "/tmp/my-embedded-ectd-cluster"
+
+	config.ListenPeerUrls = parseEtcdUrls([]string{"http://0.0.0.0:2380"})
+	config.ListenClientUrls = parseEtcdUrls([]string{"http://0.0.0.0:2379"})
+	config.AdvertisePeerUrls = parseEtcdUrls([]string{"http://localhost:2380"})
+	config.AdvertiseClientUrls = parseEtcdUrls([]string{"http://localhost:2379"})
+	config.InitialCluster = "localhost=http://localhost:2380"
+	config.LogLevel = "panic"
+
+	// enable v2
+	config.EnableV2 = true
+
+	etcd, err := embed.StartEtcd(config)
+	require.NoError(t, err)
+
+	defer etcd.Close()
+
+	clientConfig := client.Config{Endpoints: []string{"http://127.0.0.1:2379"}}
+
+	c, err := client.New(clientConfig)
+	require.NoError(t, err)
+
+	kapi := client.NewKeysAPI(c)
+	require.NotNil(t, kapi)
+
+	time.Sleep(1 * time.Second)
+
+	t.Run("provider creates ok", func(t *testing.T) {
+		t.Parallel()
+
+		p, err := NewProvider(ctx, Config{EtcdConfig: clientConfig})
+		require.NoError(t, err)
+		require.NotNil(t, p)
+	})
+
+	t.Run("provider invalid config error", func(t *testing.T) {
+		t.Parallel()
+
+		invalidClientConfig := client.Config{Endpoints: []string{"http://0.0.0.0:23803"}}
+
+		p, err := NewProvider(ctx, Config{EtcdConfig: invalidClientConfig})
+		require.NoError(t, err)
+		require.NotNil(t, p)
+
+		_, err = p.GetTopology()
+		require.Error(t, err)
+	})
+
+	t.Run("nodes error", func(t *testing.T) {
+
+		nodesErrorPath := "/no-nodes"
+
+		p, err := NewProvider(ctx, Config{EtcdConfig: clientConfig, Path: nodesErrorPath})
+		require.NoError(t, err)
+		require.NotNil(t, p)
+
+		_, err = kapi.Set(ctx, nodesErrorPath, "test", &client.SetOptions{})
+		require.NoError(t, err)
+
+		_, err = p.GetTopology()
+		require.ErrorIs(t, err, ErrNodesError)
+	})
+
+	t.Run("no clusters or instances nodes error", func(t *testing.T) {
+		nodesClusterErrPath := "/test-nodes-cluster-instances-error"
+
+		p, err := NewProvider(ctx, Config{EtcdConfig: clientConfig, Path: nodesClusterErrPath})
+		require.NoError(t, err)
+		require.NotNil(t, p)
+
+		_, err = kapi.Set(ctx, nodesClusterErrPath, "", &client.SetOptions{Dir: true})
+		require.NoError(t, err)
+
+		_, err = kapi.Set(ctx, nodesClusterErrPath+"/clusters", "test", &client.SetOptions{})
+
+		require.NoError(t, err)
+
+		_, err = kapi.Set(ctx, nodesClusterErrPath+"/instances", "test", &client.SetOptions{})
+
+		require.NoError(t, err)
+
+		_, err = p.GetTopology()
+		require.NotErrorIs(t, err, ErrNodesError)
+		require.True(t, errors.Is(err, ErrClusterError) || errors.Is(err, ErrInstancesError))
+	})
+}