go-ethereum/accounts/abi/event.go
2018-01-24 10:54:13 +02:00

58 lines
1.9 KiB
Go

// Copyright 2016 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 abi
import (
"fmt"
"strings"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
)
// Event is an event potentially triggered by the EVM's LOG mechanism. The Event
// holds type information (inputs) about the yielded output. Anonymous events
// don't get the signature canonical representation as the first LOG topic.
type Event struct {
Name string
Anonymous bool
Inputs Arguments
}
func (event Event) String() string {
inputs := make([]string, len(event.Inputs))
for i, input := range event.Inputs {
inputs[i] = fmt.Sprintf("%v %v", input.Name, input.Type)
if input.Indexed {
inputs[i] = fmt.Sprintf("%v indexed %v", input.Name, input.Type)
}
}
return fmt.Sprintf("event %v(%v)", event.Name, strings.Join(inputs, ", "))
}
// Id returns the canonical representation of the event's signature used by the
// abi definition to identify event names and types.
func (e Event) Id() common.Hash {
types := make([]string, len(e.Inputs))
i := 0
for _, input := range e.Inputs {
types[i] = input.Type.String()
i++
}
return common.BytesToHash(crypto.Keccak256([]byte(fmt.Sprintf("%v(%v)", e.Name, strings.Join(types, ",")))))
}