Method Client

dgraphtest/local_cluster.go:1013–1058

Client returns a grpc client that can talk to any Alpha in the cluster

()

// Client returns a grpc client that can talk to any Alpha in the cluster
func (c *LocalCluster) Client() (*dgraphapi.GrpcClient, func(), error) {
	// TODO(aman): can we cache the connections?
	retryPolicy := `{
		"methodConfig": [{
			"retryPolicy": {
				"MaxAttempts": 4,
				"InitialBackoff": ".01s",
				"MaxBackoff": ".01s",
				"BackoffMultiplier": 1.0,
				"RetryableStatusCodes": [ "UNAVAILABLE" ]
			}
		}]
	}`
	var apiClients []api.DgraphClient
	var conns []*grpc.ClientConn
	for _, aa := range c.alphas {
		if !aa.isRunning {
			continue
		}
		url, err := aa.alphaURL(c)
		if err != nil {
			return nil, nil, errors.Wrap(err, "error getting health URL")
		}
		conn, err := grpc.NewClient(url,
			grpc.WithTransportCredentials(insecure.NewCredentials()),
			grpc.WithDefaultServiceConfig(retryPolicy))
		if err != nil {
			return nil, nil, errors.Wrap(err, "error connecting to alpha")
		}
		conns = append(conns, conn)
		apiClients = append(apiClients, api.NewDgraphClient(conn))
	}

	if len(apiClients) == 0 {
		return nil, nil, errors.New("no alphas running")
	}
	client := dgo.NewDgraphClient(apiClients...)
	cleanup := func() {
		for _, conn := range conns {
			if err := conn.Close(); err != nil {
				log.Printf("[WARNING] problem closing connection: %v", err)
			}
		}
	}
	return &dgraphapi.GrpcClient{Dgraph: client}, cleanup, nil
}

func (c *LocalCluster) AlphaClient(id int) (*dgraphapi.GrpcClient, func(), error) {
	alpha := c.alphas[id]