github.com/codingfuture/orig-energi3@v0.8.4/accounts/abi/event.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package abi
    18  
    19  import (
    20  	"fmt"
    21  	"strings"
    22  
    23  	"github.com/ethereum/go-ethereum/common"
    24  	"github.com/ethereum/go-ethereum/crypto"
    25  )
    26  
    27  // Event is an event potentially triggered by the EVM's LOG mechanism. The Event
    28  // holds type information (inputs) about the yielded output. Anonymous events
    29  // don't get the signature canonical representation as the first LOG topic.
    30  type Event struct {
    31  	Name      string
    32  	Anonymous bool
    33  	Inputs    Arguments
    34  }
    35  
    36  func (e Event) String() string {
    37  	inputs := make([]string, len(e.Inputs))
    38  	for i, input := range e.Inputs {
    39  		inputs[i] = fmt.Sprintf("%v %v", input.Type, input.Name)
    40  		if input.Indexed {
    41  			inputs[i] = fmt.Sprintf("%v indexed %v", input.Type, input.Name)
    42  		}
    43  	}
    44  	return fmt.Sprintf("event %v(%v)", e.Name, strings.Join(inputs, ", "))
    45  }
    46  
    47  // Id returns the canonical representation of the event's signature used by the
    48  // abi definition to identify event names and types.
    49  func (e Event) Id() common.Hash {
    50  	types := make([]string, len(e.Inputs))
    51  	i := 0
    52  	for _, input := range e.Inputs {
    53  		types[i] = input.Type.String()
    54  		i++
    55  	}
    56  	return common.BytesToHash(crypto.Keccak256([]byte(fmt.Sprintf("%v(%v)", e.Name, strings.Join(types, ",")))))
    57  }