restructured eth rpc API

rpc/shared/errors.go

@@ -0,0 +1,96 @@
+package shared
+
+import "fmt"
+
+type InvalidTypeError struct {
+	method string
+	msg    string
+}
+
+func (e *InvalidTypeError) Error() string {
+	return fmt.Sprintf("invalid type on field %s: %s", e.method, e.msg)
+}
+
+func NewInvalidTypeError(method, msg string) *InvalidTypeError {
+	return &InvalidTypeError{
+		method: method,
+		msg:    msg,
+	}
+}
+
+type InsufficientParamsError struct {
+	have int
+	want int
+}
+
+func (e *InsufficientParamsError) Error() string {
+	return fmt.Sprintf("insufficient params, want %d have %d", e.want, e.have)
+}
+
+func NewInsufficientParamsError(have int, want int) *InsufficientParamsError {
+	return &InsufficientParamsError{
+		have: have,
+		want: want,
+	}
+}
+
+type NotImplementedError struct {
+	Method string
+}
+
+func (e *NotImplementedError) Error() string {
+	return fmt.Sprintf("%s method not implemented", e.Method)
+}
+
+func NewNotImplementedError(method string) *NotImplementedError {
+	return &NotImplementedError{
+		Method: method,
+	}
+}
+
+type DecodeParamError struct {
+	err string
+}
+
+func (e *DecodeParamError) Error() string {
+	return fmt.Sprintf("could not decode, %s", e.err)
+
+}
+
+func NewDecodeParamError(errstr string) error {
+	return &DecodeParamError{
+		err: errstr,
+	}
+}
+
+type ValidationError struct {
+	ParamName string
+	msg       string
+}
+
+func (e *ValidationError) Error() string {
+	return fmt.Sprintf("%s not valid, %s", e.ParamName, e.msg)
+}
+
+func NewValidationError(param string, msg string) error {
+	return &ValidationError{
+		ParamName: param,
+		msg:       msg,
+	}
+}
+
+type NotAvailableError struct {
+	Method string
+	Reason string
+}
+
+func (e *NotAvailableError) Error() string {
+	return fmt.Sprintf("%s method not available: %s", e.Method, e.Reason)
+}
+
+func NewNotAvailableError(method string, reason string) *NotAvailableError {
+	return &NotAvailableError{
+		Method: method,
+		Reason: reason,
+	}
+}

rpc/shared/types.go

@@ -0,0 +1,38 @@
+package shared
+
+import "encoding/json"
+
+// RPC request
+type Request struct {
+	Id      interface{}     `json:"id"`
+	Jsonrpc string          `json:"jsonrpc"`
+	Method  string          `json:"method"`
+	Params  json.RawMessage `json:"params"`
+}
+
+// RPC response
+type Response struct {
+	Id      interface{} `json:"id"`
+	Jsonrpc string      `json:"jsonrpc"`
+}
+
+// RPC success response
+type SuccessResponse struct {
+	Id      interface{} `json:"id"`
+	Jsonrpc string      `json:"jsonrpc"`
+	Result  interface{} `json:"result"`
+}
+
+// RPC error response
+type ErrorResponse struct {
+	Id      interface{}  `json:"id"`
+	Jsonrpc string       `json:"jsonrpc"`
+	Error   *ErrorObject `json:"error"`
+}
+
+// RPC error response details
+type ErrorObject struct {
+	Code    int    `json:"code"`
+	Message string `json:"message"`
+	// Data    interface{} `json:"data"`
+}