Tablet move and group removal

dgraph/cmd/zero/zero.go

@@ -356,6 +356,10 @@ func (s *Server) removeNode(ctx context.Context, nodeId uint64, groupId uint32)
 	if _, ok := s.state.Groups[groupId].Members[nodeId]; !ok {
 		return x.Errorf("No node with nodeId %d found in group %d", nodeId, groupId)
 	}
+	if len(s.state.Groups[groupId].Members) == 1 && len(s.state.Groups[groupId].Tablets) > 0 {
+		return x.Errorf("Move all tablets from group %d before removing the last node", groupId)
+	}
+
 	return s.Node.proposeAndWait(ctx, zp)
 }
 

ee/backup/systest/backup_test.go

@@ -59,7 +59,7 @@ func BackupSetup(t *testing.T, c *dgo.Dgraph) {
 	require.NoError(t, err)
 	require.NoError(t, c.Alter(ctx, &api.Operation{Schema: string(schema)}))
 
-	fp, err := os.Open(`data/goldendata_export.rdf.gz`)
+	fp, err := os.Open(`../../../systest/data/goldendata_export.rdf.gz`)
 	x.Check(err)
 	defer fp.Close()
 

systest/nodes_test.go

@@ -0,0 +1,226 @@
+/*
+ * Copyright 2018 Dgraph Labs, Inc. and Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"compress/gzip"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/dgraph-io/dgo"
+	"github.com/dgraph-io/dgo/protos/api"
+	"github.com/dgraph-io/dgraph/x"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc"
+)
+
+func TestNodes(t *testing.T) {
+	wrap := func(fn func(*testing.T, *dgo.Dgraph)) func(*testing.T) {
+		return func(t *testing.T) {
+			conn, err := grpc.Dial("localhost:9180", grpc.WithInsecure())
+			x.Check(err)
+			dg := dgo.NewDgraphClient(api.NewDgraphClient(conn))
+			fn(t, dg)
+		}
+	}
+
+	t.Run("setup test data", wrap(NodesSetup))
+	t.Run("move tablets from 3", wrap(NodesMoveTablets3))
+	t.Run("test query 1", wrap(NodesTestQuery))
+	t.Run("move tablets from 2", wrap(NodesMoveTablets2))
+	t.Run("test query 2", wrap(NodesTestQuery))
+	t.Run("cleanup", wrap(NodesCleanup))
+}
+
+func NodesSetup(t *testing.T, c *dgo.Dgraph) {
+	ctx := context.Background()
+
+	require.NoError(t, c.Alter(ctx, &api.Operation{DropAll: true}))
+
+	schema, err := ioutil.ReadFile(`data/goldendata.schema`)
+	require.NoError(t, err)
+	require.NoError(t, c.Alter(ctx, &api.Operation{Schema: string(schema)}))
+
+	fp, err := os.Open(`data/goldendata_export.rdf.gz`)
+	x.Check(err)
+	defer fp.Close()
+
+	gz, err := gzip.NewReader(fp)
+	x.Check(err)
+	defer gz.Close()
+
+	var (
+		cnt int
+		bb  bytes.Buffer
+	)
+
+	reader := bufio.NewReader(gz)
+	for {
+		b, err := reader.ReadBytes('\n')
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			x.Check(err)
+		}
+		bb.Write(b)
+		cnt++
+		if cnt%100 == 0 {
+			_, err = c.NewTxn().Mutate(ctx, &api.Mutation{
+				CommitNow: true,
+				SetNquads: bb.Bytes(),
+			})
+			x.Check(err)
+			bb.Reset()
+		}
+	}
+}
+
+func NodesCleanup(t *testing.T, c *dgo.Dgraph) {
+	require.NoError(t, c.Alter(context.Background(), &api.Operation{DropAll: true}))
+}
+
+type response struct {
+	Groups map[string]struct {
+		Members map[string]interface{} `json:"members"`
+		Tablets map[string]struct {
+			GroupID   int    `json:"groupId"`
+			Predicate string `json:"predicate"`
+		} `json:"tablets"`
+	} `json:"groups"`
+}
+
+func getState() (*response, error) {
+	resp, err := http.Get("http://localhost:6080/state")
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	b, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var st response
+	if err := json.Unmarshal(b, &st); err != nil {
+		return nil, err
+	}
+	return &st, nil
+}
+
+func NodesMoveTablets3(t *testing.T, c *dgo.Dgraph) {
+	state1, err := getState()
+	require.NoError(t, err)
+
+	for pred := range state1.Groups["3"].Tablets {
+		url := fmt.Sprintf("http://localhost:6080/moveTablet?tablet=%s&group=2", pred)
+		resp, err := http.Get(url)
+		require.NoError(t, err)
+		resp.Body.Close()
+		time.Sleep(time.Second)
+	}
+
+	state2, err := getState()
+	require.NoError(t, err)
+
+	if len(state2.Groups["3"].Tablets) > 0 {
+		t.Errorf("moving tablets failed")
+	}
+
+	resp, err := http.Get("http://localhost:6080/removeNode?group=3&id=3")
+	require.NoError(t, err)
+	resp.Body.Close()
+
+	state2, err = getState()
+	require.NoError(t, err)
+
+	if _, ok := state2.Groups["3"]; ok {
+		t.Errorf("node removal failed")
+	}
+}
+
+func NodesMoveTablets2(t *testing.T, c *dgo.Dgraph) {
+	state1, err := getState()
+	require.NoError(t, err)
+
+	for pred := range state1.Groups["2"].Tablets {
+		url := fmt.Sprintf("http://localhost:6080/moveTablet?tablet=%s&group=1", pred)
+		resp, err := http.Get(url)
+		require.NoError(t, err)
+		resp.Body.Close()
+		time.Sleep(time.Second)
+	}
+
+	state2, err := getState()
+	require.NoError(t, err)
+
+	if len(state2.Groups["2"].Tablets) > 0 {
+		t.Errorf("moving tablets failed")
+	}
+
+	resp, err := http.Get("http://localhost:6080/removeNode?group=2&id=2")
+	require.NoError(t, err)
+	resp.Body.Close()
+
+	state2, err = getState()
+	require.NoError(t, err)
+
+	if _, ok := state2.Groups["2"]; ok {
+		t.Errorf("node removal failed")
+	}
+}
+
+func NodesTestQuery(t *testing.T, c *dgo.Dgraph) {
+	resp, err := c.NewTxn().Query(context.Background(), `
+	{
+	q(func:anyofterms(name@en, "good bad"), first: 5) {
+		name@en
+	}
+	}`)
+	require.NoError(t, err)
+
+	CompareJSON(t, `
+	{
+		"q": [
+			{
+				"name@en": "Such Good People"
+			},
+			{
+				"name@en": "You will come good"
+			},
+			{
+				"name@en": "A Good Match"
+			},
+			{
+				"name@en": "A Good Wife"
+			},
+			{
+				"name@en": "Good"
+			}
+		]
+	}`, string(resp.GetJson()))
+}