diff --git a/go.mod b/go.mod
index 91f00e61ba..fc8849ecdf 100644
--- a/go.mod
+++ b/go.mod
@@ -10,6 +10,6 @@ require (
 	github.com/neelance/parallel v0.0.0-20160708114440-4de9ce63d14c
 	github.com/pkg/errors v0.8.0
 	github.com/sourcegraph/go-langserver v0.0.0-20180410094615-6d56335e3448
-	github.com/sourcegraph/jsonrpc2 v0.0.0-20180501180217-a3d86c792f0f
+	github.com/sourcegraph/jsonrpc2 v0.1.0
 	golang.org/x/net v0.0.0-20180420171651-5f9ae10d9af5
 )
diff --git a/go.sum b/go.sum
index 1225a325d7..3c8fcb8ce6 100644
--- a/go.sum
+++ b/go.sum
@@ -14,5 +14,7 @@ github.com/sourcegraph/go-langserver v0.0.0-20180410094615-6d56335e3448 h1:1qFoN
 github.com/sourcegraph/go-langserver v0.0.0-20180410094615-6d56335e3448/go.mod h1:bBMjfpzEHd6ijPRoQ7f+knFfw+e8R+W158/MsqAy77c=
 github.com/sourcegraph/jsonrpc2 v0.0.0-20180501180217-a3d86c792f0f h1:mHcjtPCPBj4hKeRIwIU/R+Tn6TEBvDZPQnhOquzzAgA=
 github.com/sourcegraph/jsonrpc2 v0.0.0-20180501180217-a3d86c792f0f/go.mod h1:eESpbCslcLDs8j2D7IEdGVgul7xuk9odqDTaor30IUU=
+github.com/sourcegraph/jsonrpc2 v0.1.0 h1:ohJHjZ+PcaLxDUjqk2NC3tIGsVa5bXThe1ZheSXOjuk=
+github.com/sourcegraph/jsonrpc2 v0.1.0/go.mod h1:ZafdZgk/axhT1cvZAPOhw+95nz2I/Ra5qMlU4gTRwIo=
 golang.org/x/net v0.0.0-20180420171651-5f9ae10d9af5 h1:ylIG3jIeS45kB0W95N19kS62fwermjMYLIyybf8xh9M=
 golang.org/x/net v0.0.0-20180420171651-5f9ae10d9af5/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/.travis.yml b/vendor/github.com/sourcegraph/jsonrpc2/.travis.yml
index 75e6db9944..7b2f9de0fc 100644
--- a/vendor/github.com/sourcegraph/jsonrpc2/.travis.yml
+++ b/vendor/github.com/sourcegraph/jsonrpc2/.travis.yml
@@ -1,6 +1,6 @@
 language: go
 go: 
- - 1.8
+ - 1.x
 
 script:
  - go test -race -v ./...
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/README.md b/vendor/github.com/sourcegraph/jsonrpc2/README.md
index afad9a4080..d2406ab078 100644
--- a/vendor/github.com/sourcegraph/jsonrpc2/README.md
+++ b/vendor/github.com/sourcegraph/jsonrpc2/README.md
@@ -1,4 +1,4 @@
-# jsonrpc2: JSON-RPC 2.0 implementation for Go [![Build Status](https://travis-ci.org/sourcegraph/jsonrpc2.svg)](https://travis-ci.org/sourcegraph/jsonrpc2) [![Sourcegraph](https://sourcegraph.com/github.com/sourcegraph/jsonrpc2/-/badge.svg)](https://sourcegraph.com/github.com/sourcegraph/jsonrpc2?badge)
+# jsonrpc2: JSON-RPC 2.0 implementation for Go [![Build Status](https://travis-ci.org/sourcegraph/jsonrpc2.svg)](https://travis-ci.org/sourcegraph/jsonrpc2) [![Sourcegraph](https://sourcegraph.com/github.com/sourcegraph/jsonrpc2/-/badge.svg)](https://sourcegraph.com/github.com/sourcegraph/jsonrpc2?badge) [![GoDoc](https://godoc.org/github.com/sourcegraph/jsonrpc2?status.svg)](https://godoc.org/github.com/sourcegraph/jsonrpc2)
 
 
 Package jsonrpc2 provides a [Go](https://golang.org) implementation of [JSON-RPC 2.0](http://www.jsonrpc.org/specification).
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/call_opt.go b/vendor/github.com/sourcegraph/jsonrpc2/call_opt.go
index b554baca87..73fe9c213b 100644
--- a/vendor/github.com/sourcegraph/jsonrpc2/call_opt.go
+++ b/vendor/github.com/sourcegraph/jsonrpc2/call_opt.go
@@ -28,3 +28,12 @@ func PickID(id ID) CallOption {
 		return nil
 	})
 }
+
+// StringID returns a call option that instructs the request ID to be set as a
+// string.
+func StringID() CallOption {
+	return callOptionFunc(func(r *Request) error {
+		r.ID.IsString = true
+		return nil
+	})
+}
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/conn_opt.go b/vendor/github.com/sourcegraph/jsonrpc2/conn_opt.go
index 0a4290437f..3779d7f0fb 100644
--- a/vendor/github.com/sourcegraph/jsonrpc2/conn_opt.go
+++ b/vendor/github.com/sourcegraph/jsonrpc2/conn_opt.go
@@ -2,10 +2,15 @@ package jsonrpc2
 
 import (
 	"encoding/json"
-	"log"
 	"sync"
 )
 
+// Logger interface implements one method - Printf.
+// You can use the stdlib logger *log.Logger
+type Logger interface {
+	Printf(format string, v ...interface{})
+}
+
 // ConnOpt is the type of function that can be passed to NewConn to
 // customize the Conn before it is created.
 type ConnOpt func(*Conn)
@@ -24,7 +29,7 @@ func OnSend(f func(*Request, *Response)) ConnOpt {
 
 // LogMessages causes all messages sent and received on conn to be
 // logged using the provided logger.
-func LogMessages(log *log.Logger) ConnOpt {
+func LogMessages(logger Logger) ConnOpt {
 	return func(c *Conn) {
 		// Remember reqs we have received so we can helpfully show the
 		// request method in OnSend for responses.
@@ -33,18 +38,21 @@ func LogMessages(log *log.Logger) ConnOpt {
 			reqMethods = map[ID]string{}
 		)
 
+		// Set custom logger from provided input
+		c.logger = logger
+
 		OnRecv(func(req *Request, resp *Response) {
 			switch {
-			case req != nil && resp == nil:
+			case req != nil:
 				mu.Lock()
 				reqMethods[req.ID] = req.Method
 				mu.Unlock()
 
 				params, _ := json.Marshal(req.Params)
 				if req.Notif {
-					log.Printf("--> notif: %s: %s", req.Method, params)
+					logger.Printf("jsonrpc2: --> notif: %s: %s\n", req.Method, params)
 				} else {
-					log.Printf("--> request #%s: %s: %s", req.ID, req.Method, params)
+					logger.Printf("jsonrpc2: --> request #%s: %s: %s\n", req.ID, req.Method, params)
 				}
 
 			case resp != nil:
@@ -57,10 +65,10 @@ func LogMessages(log *log.Logger) ConnOpt {
 				switch {
 				case resp.Result != nil:
 					result, _ := json.Marshal(resp.Result)
-					log.Printf("--> result #%s: %s: %s", resp.ID, method, result)
+					logger.Printf("jsonrpc2: --> result #%s: %s: %s\n", resp.ID, method, result)
 				case resp.Error != nil:
 					err, _ := json.Marshal(resp.Error)
-					log.Printf("--> error #%s: %s: %s", resp.ID, method, err)
+					logger.Printf("jsonrpc2: --> error #%s: %s: %s\n", resp.ID, method, err)
 				}
 			}
 		})(c)
@@ -69,9 +77,9 @@ func LogMessages(log *log.Logger) ConnOpt {
 			case req != nil:
 				params, _ := json.Marshal(req.Params)
 				if req.Notif {
-					log.Printf("<-- notif: %s: %s", req.Method, params)
+					logger.Printf("jsonrpc2: <-- notif: %s: %s\n", req.Method, params)
 				} else {
-					log.Printf("<-- request #%s: %s: %s", req.ID, req.Method, params)
+					logger.Printf("jsonrpc2: <-- request #%s: %s: %s\n", req.ID, req.Method, params)
 				}
 
 			case resp != nil:
@@ -85,10 +93,10 @@ func LogMessages(log *log.Logger) ConnOpt {
 
 				if resp.Result != nil {
 					result, _ := json.Marshal(resp.Result)
-					log.Printf("<-- result #%s: %s: %s", resp.ID, method, result)
+					logger.Printf("jsonrpc2: <-- result #%s: %s: %s\n", resp.ID, method, result)
 				} else {
 					err, _ := json.Marshal(resp.Error)
-					log.Printf("<-- error #%s: %s: %s", resp.ID, method, err)
+					logger.Printf("jsonrpc2: <-- error #%s: %s: %s\n", resp.ID, method, err)
 				}
 			}
 		})(c)
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/go.mod b/vendor/github.com/sourcegraph/jsonrpc2/go.mod
new file mode 100644
index 0000000000..95cca53caa
--- /dev/null
+++ b/vendor/github.com/sourcegraph/jsonrpc2/go.mod
@@ -0,0 +1,5 @@
+module github.com/sourcegraph/jsonrpc2
+
+go 1.12
+
+require github.com/gorilla/websocket v1.4.1
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/go.sum b/vendor/github.com/sourcegraph/jsonrpc2/go.sum
new file mode 100644
index 0000000000..1f9b923e90
--- /dev/null
+++ b/vendor/github.com/sourcegraph/jsonrpc2/go.sum
@@ -0,0 +1,2 @@
+github.com/gorilla/websocket v1.4.1 h1:q7AeDBpnBk8AogcD4DSag/Ukw/KV+YhzLj2bP5HvKCM=
+github.com/gorilla/websocket v1.4.1/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/handler_with_error.go b/vendor/github.com/sourcegraph/jsonrpc2/handler_with_error.go
index 6f056ccadc..2bd5c1d900 100644
--- a/vendor/github.com/sourcegraph/jsonrpc2/handler_with_error.go
+++ b/vendor/github.com/sourcegraph/jsonrpc2/handler_with_error.go
@@ -2,7 +2,6 @@ package jsonrpc2
 
 import (
 	"context"
-	"log"
 )
 
 // HandlerWithError implements Handler by calling the func for each
@@ -11,6 +10,7 @@ func HandlerWithError(handleFunc func(context.Context, *Conn, *Request) (result
 	return &HandlerWithErrorConfigurer{handleFunc: handleFunc}
 }
 
+// HandlerWithErrorConfigurer is a handler created by HandlerWithError.
 type HandlerWithErrorConfigurer struct {
 	handleFunc        func(context.Context, *Conn, *Request) (result interface{}, err error)
 	suppressErrClosed bool
@@ -21,7 +21,7 @@ func (h *HandlerWithErrorConfigurer) Handle(ctx context.Context, conn *Conn, req
 	result, err := h.handleFunc(ctx, conn, req)
 	if req.Notif {
 		if err != nil {
-			log.Printf("jsonrpc2 handler: notification %q handling error: %s", req.Method, err)
+			conn.logger.Printf("jsonrpc2 handler: notification %q handling error: %v\n", req.Method, err)
 		}
 		return
 	}
@@ -41,7 +41,7 @@ func (h *HandlerWithErrorConfigurer) Handle(ctx context.Context, conn *Conn, req
 	if !req.Notif {
 		if err := conn.SendResponse(ctx, resp); err != nil {
 			if err != ErrClosed || !h.suppressErrClosed {
-				log.Printf("jsonrpc2 handler: sending response %s: %s", resp.ID, err)
+				conn.logger.Printf("jsonrpc2 handler: sending response %s: %v\n", resp.ID, err)
 			}
 		}
 	}
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/jsonrpc2.go b/vendor/github.com/sourcegraph/jsonrpc2/jsonrpc2.go
index 3e0763d73f..005b65c07f 100644
--- a/vendor/github.com/sourcegraph/jsonrpc2/jsonrpc2.go
+++ b/vendor/github.com/sourcegraph/jsonrpc2/jsonrpc2.go
@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"os"
 	"strconv"
 	"sync"
 )
@@ -84,11 +85,12 @@ func (r *Request) UnmarshalJSON(data []byte) error {
 		return err
 	}
 	r.Method = r2.Method
-	if r2.Params == nil {
+	switch {
+	case r2.Params == nil:
 		r.Params = &jsonNull
-	} else if len(*r2.Params) == 0 {
+	case len(*r2.Params) == 0:
 		r.Params = nil
-	} else {
+	default:
 		r.Params = r2.Params
 	}
 	r.Meta = r2.Meta
@@ -212,22 +214,20 @@ func (e *Error) Error() string {
 	return fmt.Sprintf("jsonrpc2: code %v message: %s", e.Code, e.Message)
 }
 
+// Errors defined in the JSON-RPC spec. See
+// http://www.jsonrpc.org/specification#error_object.
 const (
-	// Errors defined in the JSON-RPC spec. See
-	// http://www.jsonrpc.org/specification#error_object.
-	CodeParseError       = -32700
-	CodeInvalidRequest   = -32600
-	CodeMethodNotFound   = -32601
-	CodeInvalidParams    = -32602
-	CodeInternalError    = -32603
-	codeServerErrorStart = -32099
-	codeServerErrorEnd   = -32000
+	CodeParseError     = -32700
+	CodeInvalidRequest = -32600
+	CodeMethodNotFound = -32601
+	CodeInvalidParams  = -32602
+	CodeInternalError  = -32603
 )
 
 // Handler handles JSON-RPC requests and notifications.
 type Handler interface {
 	// Handle is called to handle a request. No other requests are handled
-	// until it returns. If you do not require strict ordering behaviour
+	// until it returns. If you do not require strict ordering behavior
 	// of received RPCs, it is suggested to wrap your handler in
 	// AsyncHandler.
 	Handle(context.Context, *Conn, *Request)
@@ -297,6 +297,8 @@ type Conn struct {
 
 	disconnect chan struct{}
 
+	logger Logger
+
 	// Set by ConnOpt funcs.
 	onRecv []func(*Request, *Response)
 	onSend []func(*Request, *Response)
@@ -315,14 +317,18 @@ var ErrClosed = errors.New("jsonrpc2: connection is closed")
 //
 // NewClient consumes conn, so you should call Close on the returned
 // client not on the given conn.
-func NewConn(ctx context.Context, stream ObjectStream, h Handler, opt ...ConnOpt) *Conn {
+func NewConn(ctx context.Context, stream ObjectStream, h Handler, opts ...ConnOpt) *Conn {
 	c := &Conn{
 		stream:     stream,
 		h:          h,
 		pending:    map[ID]*call{},
 		disconnect: make(chan struct{}),
+		logger:     log.New(os.Stderr, "", log.LstdFlags),
 	}
-	for _, opt := range opt {
+	for _, opt := range opts {
+		if opt == nil {
+			continue
+		}
 		opt(c)
 	}
 	go c.readMessages(ctx)
@@ -342,7 +348,7 @@ func (c *Conn) Close() error {
 	return c.stream.Close()
 }
 
-func (c *Conn) send(ctx context.Context, m *anyMessage, wait bool) (cc *call, err error) {
+func (c *Conn) send(_ context.Context, m *anyMessage, wait bool) (cc *call, err error) {
 	c.sending.Lock()
 	defer c.sending.Unlock()
 
@@ -360,9 +366,14 @@ func (c *Conn) send(ctx context.Context, m *anyMessage, wait bool) (cc *call, er
 	// responses.
 	if m.request != nil && wait {
 		cc = &call{request: m.request, seq: c.seq, done: make(chan error, 1)}
-		if !m.request.ID.IsString && m.request.ID.Num == 0 {
-			// unset, use next seq as call ID
-			m.request.ID.Num = c.seq
+
+		isIDUnset := len(m.request.ID.Str) == 0 && m.request.ID.Num == 0
+		if isIDUnset {
+			if m.request.ID.IsString {
+				m.request.ID.Str = strconv.FormatUint(c.seq, 10)
+			} else {
+				m.request.ID.Num = c.seq
+			}
 		}
 		id = m.request.ID
 		c.pending[id] = cc
@@ -410,21 +421,50 @@ func (c *Conn) send(ctx context.Context, m *anyMessage, wait bool) (cc *call, er
 // its result is stored in result (a pointer to a value that can be
 // JSON-unmarshaled into); otherwise, a non-nil error is returned.
 func (c *Conn) Call(ctx context.Context, method string, params, result interface{}, opts ...CallOption) error {
+	call, err := c.DispatchCall(ctx, method, params, opts...)
+	if err != nil {
+		return err
+	}
+	return call.Wait(ctx, result)
+}
+
+// DispatchCall dispatches a JSON-RPC call using the specified method
+// and params, and returns a call proxy or an error. Call Wait()
+// on the returned proxy to receive the response. Only use this
+// function if you need to do work after dispatching the request,
+// otherwise use Call.
+func (c *Conn) DispatchCall(ctx context.Context, method string, params interface{}, opts ...CallOption) (Waiter, error) {
 	req := &Request{Method: method}
 	if err := req.SetParams(params); err != nil {
-		return err
+		return Waiter{}, err
 	}
 	for _, opt := range opts {
+		if opt == nil {
+			continue
+		}
 		if err := opt.apply(req); err != nil {
-			return err
+			return Waiter{}, err
 		}
 	}
 	call, err := c.send(ctx, &anyMessage{request: req}, true)
 	if err != nil {
-		return err
+		return Waiter{}, err
 	}
+	return Waiter{call: call}, nil
+}
+
+// Waiter proxies an ongoing JSON-RPC call.
+type Waiter struct {
+	*call
+}
+
+// Wait for the result of an ongoing JSON-RPC call. If the response
+// is successful, its result is stored in result (a pointer to a
+// value that can be JSON-unmarshaled into); otherwise, a non-nil
+// error is returned.
+func (w Waiter) Wait(ctx context.Context, result interface{}) error {
 	select {
-	case err, ok := <-call.done:
+	case err, ok := <-w.call.done:
 		if !ok {
 			err = ErrClosed
 		}
@@ -432,11 +472,10 @@ func (c *Conn) Call(ctx context.Context, method string, params, result interface
 			return err
 		}
 		if result != nil {
-			if call.response.Result == nil {
-				call.response.Result = &jsonNull
+			if w.call.response.Result == nil {
+				w.call.response.Result = &jsonNull
 			}
-			// TODO(sqs): error handling
-			if err := json.Unmarshal(*call.response.Result, result); err != nil {
+			if err := json.Unmarshal(*w.call.response.Result, result); err != nil {
 				return err
 			}
 		}
@@ -458,6 +497,9 @@ func (c *Conn) Notify(ctx context.Context, method string, params interface{}, op
 		return err
 	}
 	for _, opt := range opts {
+		if opt == nil {
+			continue
+		}
 		if err := opt.apply(req); err != nil {
 			return err
 		}
@@ -535,7 +577,7 @@ func (c *Conn) readMessages(ctx context.Context) {
 
 				switch {
 				case call == nil:
-					log.Printf("jsonrpc2: ignoring response #%s with no corresponding request", id)
+					c.logger.Printf("jsonrpc2: ignoring response #%s with no corresponding request\n", id)
 
 				case resp.Error != nil:
 					call.done <- resp.Error
@@ -567,7 +609,7 @@ func (c *Conn) readMessages(ctx context.Context) {
 	c.mu.Unlock()
 	c.sending.Unlock()
 	if err != io.ErrUnexpectedEOF && !closing {
-		log.Println("jsonrpc2: protocol error:", err)
+		c.logger.Printf("jsonrpc2: protocol error: %v\n", err)
 	}
 	close(c.disconnect)
 }
@@ -633,17 +675,22 @@ func (m *anyMessage) UnmarshalJSON(data []byte) error {
 		if len(msgs) == 0 {
 			return errors.New("jsonrpc2: invalid empty batch")
 		}
-		for _, msg := range msgs {
-			if err := checkType(&msg); err != nil {
+		for i := range msgs {
+			if err := checkType(&msg{
+				ID:     msgs[i].ID,
+				Method: msgs[i].Method,
+				Result: msgs[i].Result,
+				Error:  msgs[i].Error,
+			}); err != nil {
 				return err
 			}
 		}
 	} else {
-		var msg msg
-		if err := json.Unmarshal(data, &msg); err != nil {
+		var m msg
+		if err := json.Unmarshal(data, &m); err != nil {
 			return err
 		}
-		if err := checkType(&msg); err != nil {
+		if err := checkType(&m); err != nil {
 			return err
 		}
 	}
@@ -684,8 +731,3 @@ func (v *anyValueWithExplicitNull) UnmarshalJSON(data []byte) error {
 	*v = anyValueWithExplicitNull{}
 	return json.Unmarshal(data, &v.value)
 }
-
-var (
-	errInvalidRequestJSON  = errors.New("jsonrpc2: request must be either a JSON object or JSON array")
-	errInvalidResponseJSON = errors.New("jsonrpc2: response must be either a JSON object or JSON array")
-)
diff --git a/vendor/github.com/sourcegraph/jsonrpc2/stream.go b/vendor/github.com/sourcegraph/jsonrpc2/stream.go
index f38c026ac1..e7a90253c7 100644
--- a/vendor/github.com/sourcegraph/jsonrpc2/stream.go
+++ b/vendor/github.com/sourcegraph/jsonrpc2/stream.go
@@ -162,3 +162,16 @@ func (VSCodeObjectCodec) ReadObject(stream *bufio.Reader, v interface{}) error {
 	}
 	return json.NewDecoder(io.LimitReader(stream, int64(contentLength))).Decode(v)
 }
+
+// PlainObjectCodec reads/writes plain JSON-RPC 2.0 objects without a header.
+type PlainObjectCodec struct{}
+
+// WriteObject implements ObjectCodec.
+func (PlainObjectCodec) WriteObject(stream io.Writer, v interface{}) error {
+	return json.NewEncoder(stream).Encode(v)
+}
+
+// ReadObject implements ObjectCodec.
+func (PlainObjectCodec) ReadObject(stream *bufio.Reader, v interface{}) error {
+	return json.NewDecoder(stream).Decode(v)
+}
diff --git a/vendor/modules.txt b/vendor/modules.txt
index da14cd6e9b..7617898fc5 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -1,19 +1,29 @@
 # github.com/google/uuid v0.0.0-20161128191214-064e2069ce9c
+## explicit
 github.com/google/uuid
+# github.com/gorilla/websocket v1.4.1
+## explicit
 # github.com/hashicorp/errwrap v0.0.0-20141028054710-7554cd9344ce
+## explicit
 github.com/hashicorp/errwrap
 # github.com/hashicorp/go-multierror v0.0.0-20171204182908-b7773ae21874
+## explicit
 github.com/hashicorp/go-multierror
 # github.com/neelance/parallel v0.0.0-20160708114440-4de9ce63d14c
+## explicit
 github.com/neelance/parallel
 # github.com/pkg/errors v0.8.0
+## explicit
 github.com/pkg/errors
 # github.com/sourcegraph/go-langserver v0.0.0-20180410094615-6d56335e3448
+## explicit
 github.com/sourcegraph/go-langserver/pkg/lsp
 github.com/sourcegraph/go-langserver/pkg/lspext
-# github.com/sourcegraph/jsonrpc2 v0.0.0-20180501180217-a3d86c792f0f
+# github.com/sourcegraph/jsonrpc2 v0.1.0
+## explicit
 github.com/sourcegraph/jsonrpc2
 # golang.org/x/net v0.0.0-20180420171651-5f9ae10d9af5
-golang.org/x/net/trace
+## explicit
 golang.org/x/net/context
 golang.org/x/net/internal/timeseries
+golang.org/x/net/trace