path: root/rpc/server_test.go

// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package rpc

import (
    "encoding/json"
    "fmt"
    "reflect"
    "testing"
    "time"

    "golang.org/x/net/context"
)

type Service struct{}

type Args struct {
    S string
}

func (s *Service) NoArgsRets() {
}

type Result struct {
    String string
    Int    int
    Args   *Args
}

func (s *Service) Echo(str string, i int, args *Args) Result {
    return Result{str, i, args}
}

func (s *Service) EchoWithCtx(ctx context.Context, str string, i int, args *Args) Result {
    return Result{str, i, args}
}

func (s *Service) Rets() (string, error) {
    return "", nil
}

func (s *Service) InvalidRets1() (error, string) {
    return nil, ""
}

func (s *Service) InvalidRets2() (string, string) {
    return "", ""
}

func (s *Service) InvalidRets3() (string, string, error) {
    return "", "", nil
}

func (s *Service) Subscription(ctx context.Context) (Subscription, error) {
    return nil, nil
}

func (s *Service) SubsriptionWithArgs(ctx context.Context, a, b int) (Subscription, error) {
    return nil, nil
}

func TestServerRegisterName(t *testing.T) {
    server := NewServer()
    service := new(Service)

    if err := server.RegisterName("calc", service); err != nil {
        t.Fatalf("%v", err)
    }

    if len(server.services) != 2 {
        t.Fatalf("Expected 2 service entries, got %d", len(server.services))
    }

    svc, ok := server.services["calc"]
    if !ok {
        t.Fatalf("Expected service calc to be registered")
    }

    if len(svc.callbacks) != 4 {
        t.Errorf("Expected 4 callbacks for service 'calc', got %d", len(svc.callbacks))
    }

    if len(svc.subscriptions) != 2 {
        t.Errorf("Expected 2 subscriptions for service 'calc', got %d", len(svc.subscriptions))
    }
}

// dummy codec used for testing RPC method execution
type ServerTestCodec struct {
    counter int
    input   []byte
    output  string
    closer  chan interface{}
}

func (c *ServerTestCodec) ReadRequestHeaders() ([]rpcRequest, bool, RPCError) {
    c.counter += 1

    if c.counter == 1 {
        var req JSONRequest
        json.Unmarshal(c.input, &req)
        return []rpcRequest{rpcRequest{id: *req.Id, isPubSub: false, service: "test", method: req.Method, params: req.Payload}}, false, nil
    }

    // requests are executes in parallel, wait a bit before returning an error so that the previous request has time to
    // be executed
    timer := time.NewTimer(time.Duration(2) * time.Second)
    <-timer.C

    return nil, false, &invalidRequestError{"connection closed"}
}

func (c *ServerTestCodec) ParseRequestArguments(argTypes []reflect.Type, payload interface{}) ([]reflect.Value, RPCError) {

    args, _ := payload.(json.RawMessage)

    argValues := make([]reflect.Value, len(argTypes))
    params := make([]interface{}, len(argTypes))

    n, err := countArguments(args)
    if err != nil {
        return nil, &invalidParamsError{err.Error()}
    }
    if n != len(argTypes) {
        return nil, &invalidParamsError{fmt.Sprintf("insufficient params, want %d have %d", len(argTypes), n)}

    }

    for i, t := range argTypes {
        if t.Kind() == reflect.Ptr {
            // values must be pointers for the Unmarshal method, reflect.
            // Dereference otherwise reflect.New would create **SomeType
            argValues[i] = reflect.New(t.Elem())
            params[i] = argValues[i].Interface()

            // when not specified blockNumbers are by default latest (-1)
            if blockNumber, ok := params[i].(*BlockNumber); ok {
                *blockNumber = BlockNumber(-1)
            }
        } else {
            argValues[i] = reflect.New(t)
            params[i] = argValues[i].Interface()

            // when not specified blockNumbers are by default latest (-1)
            if blockNumber, ok := params[i].(*BlockNumber); ok {
                *blockNumber = BlockNumber(-1)
            }
        }
    }

    if err := json.Unmarshal(args, &params); err != nil {
        return nil, &invalidParamsError{err.Error()}
    }

    // Convert pointers back to values where necessary
    for i, a := range argValues {
        if a.Kind() != argTypes[i].Kind() {
            argValues[i] = reflect.Indirect(argValues[i])
        }
    }

    return argValues, nil
}

func (c *ServerTestCodec) CreateResponse(id int64, reply interface{}) interface{} {
    return &JSONSuccessResponse{Version: jsonRPCVersion, Id: id, Result: reply}
}

func (c *ServerTestCodec) CreateErrorResponse(id *int64, err RPCError) interface{} {
    return &JSONErrResponse{Version: jsonRPCVersion, Id: id, Error: JSONError{Code: err.Code(), Message: err.Error()}}
}

func (c *ServerTestCodec) CreateErrorResponseWithInfo(id *int64, err RPCError, info interface{}) interface{} {
    return &JSONErrResponse{Version: jsonRPCVersion, Id: id,
        Error: JSONError{Code: err.Code(), Message: err.Error(), Data: info}}
}

func (c *ServerTestCodec) CreateNotification(subid string, event interface{}) interface{} {
    return &jsonNotification{Version: jsonRPCVersion, Method: notificationMethod,
        Params: jsonSubscription{Subscription: subid, Result: event}}
}

func (c *ServerTestCodec) Write(msg interface{}) error {
    if len(c.output) == 0 { // only capture first response
        if o, err := json.Marshal(msg); err != nil {
            return err
        } else {
            c.output = string(o)
        }
    }

    return nil
}

func (c *ServerTestCodec) Close() {
    close(c.closer)
}

func (c *ServerTestCodec) Closed() <-chan interface{} {
    return c.closer
}

func TestServerMethodExecution(t *testing.T) {
    server := NewServer()
    service := new(Service)

    if err := server.RegisterName("test", service); err != nil {
        t.Fatalf("%v", err)
    }

    id := int64(12345)
    req := JSONRequest{
        Method:  "echo",
        Version: "2.0",
        Id:      &id,
    }
    args := []interface{}{"string arg", 1122, &Args{"qwerty"}}
    req.Payload, _ = json.Marshal(&args)

    input, _ := json.Marshal(&req)
    codec := &ServerTestCodec{input: input, closer: make(chan interface{})}
    go server.ServeCodec(codec, OptionMethodInvocation)

    <-codec.closer

    expected := `{"jsonrpc":"2.0","id":12345,"result":{"String":"string arg","Int":1122,"Args":{"S":"qwerty"}}}`

    if expected != codec.output {
        t.Fatalf("expected %s, got %s\n", expected, codec.output)
    }
}

func TestServerMethodWithCtx(t *testing.T) {
    server := NewServer()
    service := new(Service)

    if err := server.RegisterName("test", service); err != nil {
        t.Fatalf("%v", err)
    }

    id := int64(12345)
    req := JSONRequest{
        Method:  "echoWithCtx",
        Version: "2.0",
        Id:      &id,
    }
    args := []interface{}{"string arg", 1122, &Args{"qwerty"}}
    req.Payload, _ = json.Marshal(&args)

    input, _ := json.Marshal(&req)
    codec := &ServerTestCodec{input: input, closer: make(chan interface{})}
    go server.ServeCodec(codec, OptionMethodInvocation)

    <-codec.closer

    expected := `{"jsonrpc":"2.0","id":12345,"result":{"String":"string arg","Int":1122,"Args":{"S":"qwerty"}}}`

    if expected != codec.output {
        t.Fatalf("expected %s, got %s\n", expected, codec.output)
    }
}