Merge pull request #1 from space307/feature/request_id

Add passing request id through context

Author: cv21

.gitignore

@@ -0,0 +1 @@
+.idea

client.go

@@ -5,8 +5,9 @@ package jsonrpc2
 import (
 	"context"
 	"encoding/json"
-	"math/rand"
 	"net/http"
+
+	uuid "github.com/gofrs/uuid"
 )
 
 const (
@@ -33,10 +34,10 @@ func (e *ResponseError) Error() string {
 // Request represents a jsonrpc2 request.
 //easyjson:json
 type Request struct {
-	Version string      `json:"jsonrpc"`
-	Method  string      `json:"method"`
-	Params  interface{} `json:"params"`
-	Id      uint64      `json:"id"`
+	Version string           `json:"jsonrpc"`
+	Method  string           `json:"method"`
+	Params  interface{}      `json:"params"`
+	Id      *json.RawMessage `json:"id"`
 }
 
 // Request represents a jsonrpc2 response.
@@ -45,6 +46,7 @@ type Response struct {
 	Version string           `json:"jsonrpc"`
 	Result  *json.RawMessage `json:"result"`
 	Error   *json.RawMessage `json:"error"`
+	Id      *json.RawMessage `json:"id"`
 }
 
 type (
@@ -85,7 +87,20 @@ func NewClient(rpcEndpointURL string, options ...clientOption) Client {
 
 // Call makes and does jsonrpc2 request.
 func (c *client) Call(ctx context.Context, methodName string, params interface{}, result interface{}) error {
-	encodedReq, err := encodeRequest(methodName, params)
+	requestID, _ := RequestIDFromContext(ctx)
+
+	if requestID == nil {
+		reqUUID, err := uuid.NewV4()
+		if err != nil {
+			return err
+		}
+
+		// We do not use json.Marshal because we know the json representation of a string.
+		requestIDVal := json.RawMessage("\"" + reqUUID.String() + "\"")
+		requestID = &requestIDVal
+	}
+
+	encodedReq, err := encodeRequest(requestID, methodName, params)
 	if err != nil {
 		return err
 	}
@@ -98,12 +113,12 @@ func (c *client) Call(ctx context.Context, methodName string, params interface{}
 	return decodeResponse(resp, result)
 }
 
-func encodeRequest(method string, args interface{}) ([]byte, error) {
+func encodeRequest(id *json.RawMessage, method string, args interface{}) ([]byte, error) {
 	return json.Marshal(&Request{
 		Version: protocolVersionStr,
 		Method:  method,
 		Params:  args,
-		Id:      uint64(rand.Int63()),
+		Id:      id,
 	})
 }
 
@@ -131,4 +146,4 @@ func decodeResponse(r []byte, reply interface{}) error {
 	}
 
 	return json.Unmarshal(*resp.Result, reply)
-}
+}

client_easyjson.go

@@ -2,6 +2,7 @@ package jsonrpc2
 
 import (
 	"context"
+
 	"github.com/semrush/zenrpc"
 )
 
@@ -18,6 +19,5 @@ func (TestService) Divide(ctx context.Context, a int, b int) (result float32, er
 	if b == 0 {
 		return 0, zenrpc.NewStringError(-32500, "Could not divide to zero")
 	}
-	return float32(a)/float32(b), nil
+	return float32(a) / float32(b), nil
 }
-

client_server_test.go

@@ -3,12 +3,13 @@ package jsonrpc2
 import (
 	"context"
 	"fmt"
-	"github.com/semrush/zenrpc"
-	"github.com/stretchr/testify/assert"
 	"net/http"
 	"net/http/httptest"
 	"os"
 	"testing"
+
+	"github.com/semrush/zenrpc"
+	"github.com/stretchr/testify/assert"
 )
 
 var serverURL string
@@ -29,8 +30,8 @@ func Test_client_Call_Sum_Ok(t *testing.T) {
 	client := NewClient(fmt.Sprintf("%s/rpc", serverURL))
 	var val int
 	err := client.Call(context.Background(), "Sum", struct {
-		A,B int
-	}{1,2}, &val)
+		A, B int
+	}{1, 2}, &val)
 	assert.NoError(t, err)
 	assert.Equal(t, 3, val)
 }
@@ -39,8 +40,8 @@ func Test_client_Call_Div_Ok(t *testing.T) {
 	client := NewClient(fmt.Sprintf("%s/rpc", serverURL))
 	var val int
 	err := client.Call(context.Background(), "Divide", struct {
-		A,B int
-	}{4,2}, &val)
+		A, B int
+	}{4, 2}, &val)
 	assert.NoError(t, err)
 	assert.Equal(t, 2, val)
 }
@@ -49,8 +50,8 @@ func Test_client_Call_Div_Fail(t *testing.T) {
 	client := NewClient(fmt.Sprintf("%s/rpc", serverURL))
 	var val int
 	err := client.Call(context.Background(), "Divide", struct {
-		A,B int
-	}{4,0}, &val)
+		A, B int
+	}{4, 0}, &val)
 	assert.Error(t, err)
 	assert.Zero(t, val)
 }

client_test.go

@@ -0,0 +1,23 @@
+package jsonrpc2
+
+import (
+	"context"
+	"encoding/json"
+)
+
+// key is the unique and unexported ctx key for the jsonrpc package.
+type key int
+
+// keyRequestID is particular ctx key for request id field.
+var keyRequestID key
+
+// WithRequestID returns a new Context that carries id.
+func WithRequestID(ctx context.Context, id *json.RawMessage) context.Context {
+	return context.WithValue(ctx, keyRequestID, id)
+}
+
+// RequestIDFromContext returns the id value stored in ctx, if any.
+func RequestIDFromContext(ctx context.Context) (*json.RawMessage, bool) {
+	u, ok := ctx.Value(keyRequestID).(*json.RawMessage)
+	return u, ok
+}

context.go

@@ -1,12 +1,11 @@
-module github.com/cv21/jsonrpc2
+module github.com/space307/jsonrpc2
 
 go 1.12
 
 require (
+	github.com/gofrs/uuid v3.2.0+incompatible
 	github.com/gorilla/websocket v1.4.1 // indirect
 	github.com/mailru/easyjson v0.7.0
-	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
-	github.com/modern-go/reflect2 v1.0.1 // indirect
 	github.com/prometheus/client_golang v1.1.0 // indirect
 	github.com/semrush/zenrpc v1.1.1
 	github.com/stretchr/testify v1.3.0

go.mod

@@ -11,6 +11,8 @@ github.com/go-kit/kit v0.8.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2
 github.com/go-logfmt/logfmt v0.3.0/go.mod h1:Qt1PoO58o5twSAckw1HlFXLmHsOX5/0LbT9GBnD5lWE=
 github.com/go-logfmt/logfmt v0.4.0/go.mod h1:3RMwSq7FuexP4Kalkev3ejPJsZTpXXBr9+V4qmtdjCk=
 github.com/go-stack/stack v1.8.0/go.mod h1:v0f6uXyyMGvRgIKkXu+yp6POWl0qKG85gN/melR3HDY=
+github.com/gofrs/uuid v3.2.0+incompatible h1:y12jRkkFxsd7GpqdSZ+/KCs/fJbqpEXSGd4+jfEaewE=
+github.com/gofrs/uuid v3.2.0+incompatible/go.mod h1:b2aQJv3Z4Fp6yNu3cdSllBxTCLRxnplIgP/c0N/04lM=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -72,5 +74,6 @@ golang.org/x/sys v0.0.0-20190801041406-cbf593c0f2f3 h1:4y9KwBHBgBNwDbtu44R5o1fdO
 golang.org/x/sys v0.0.0-20190801041406-cbf593c0f2f3/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=