path: root/rpc/xeth.go

package rpc

import (
    "encoding/json"
    "fmt"
    "reflect"
    "sync/atomic"

    "github.com/ethereum/go-ethereum/rpc/comms"
    "github.com/ethereum/go-ethereum/rpc/shared"
)

// Xeth is a native API interface to a remote node.
type Xeth struct {
    client comms.EthereumClient
    reqId  uint32
}

// NewXeth constructs a new native API interface to a remote node.
func NewXeth(client comms.EthereumClient) *Xeth {
    return &Xeth{
        client: client,
    }
}

// Call invokes a method with the given parameters are the remote node.
func (self *Xeth) Call(method string, params []interface{}) (map[string]interface{}, error) {
    // Assemble the json RPC request
    data, err := json.Marshal(params)
    if err != nil {
        return nil, err
    }
    req := &shared.Request{
        Id:      atomic.AddUint32(&self.reqId, 1),
        Jsonrpc: "2.0",
        Method:  method,
        Params:  data,
    }
    // Send the request over and process the response
    if err := self.client.Send(req); err != nil {
        return nil, err
    }
    res, err := self.client.Recv()
    if err != nil {
        return nil, err
    }
    value, ok := res.(map[string]interface{})
    if !ok {
        return nil, fmt.Errorf("Invalid response type: have %v, want %v", reflect.TypeOf(res), reflect.TypeOf(make(map[string]interface{})))
    }
    return value, nil
}