parent
233c4171ef
commit
3cce2a17b1
@ -0,0 +1,81 @@ |
||||
'use strict' |
||||
var $ = require('jquery') |
||||
var ethJSABI = require('ethereumjs-abi') |
||||
|
||||
/** |
||||
* Register to txListener and extract events |
||||
* |
||||
*/ |
||||
class EventsDecoder { |
||||
constructor (opt = {}) { |
||||
this.txListener = opt.txListener |
||||
this.resolvedEvents = {} |
||||
} |
||||
|
||||
/** |
||||
* use Transaction Receipt to decode logs. assume that the transaction as already been resolved by txListener. |
||||
* logs are decoded only if the contract if known by remix. |
||||
* |
||||
* @param {Object} tx - transaction object |
||||
* @param {Function} cb - callback |
||||
*/ |
||||
parseLogs (tx, resolvedData, compiledContracts) { |
||||
this.txListener.resolveTransactionReceipt(tx, (error, receipt) => { |
||||
if (error) console.log(error) |
||||
this._decodeLogs(tx, receipt, resolvedData.contractName, compiledContracts) |
||||
}) |
||||
} |
||||
|
||||
eventsOf (hash) { |
||||
return this.resolvedEvents[hash] |
||||
} |
||||
|
||||
_decodeLogs (tx, receipt, contract, contracts) { |
||||
if (!contract || !receipt.logs) { |
||||
return |
||||
} |
||||
this._decodeEvents(tx, receipt.logs, contract, contracts) |
||||
} |
||||
|
||||
_eventABI (contractName, compiledContracts) { |
||||
var contractabi = JSON.parse(compiledContracts[contractName].interface) |
||||
var eventABI = {} |
||||
$.each(contractabi, function (i, funABI) { |
||||
if (funABI.type !== 'event') { |
||||
return |
||||
} |
||||
var hash = ethJSABI.eventID(funABI.name, funABI.inputs.map(function (item) { return item.type })) |
||||
eventABI[hash.toString('hex')] = { event: funABI.name, inputs: funABI.inputs } |
||||
}) |
||||
return eventABI |
||||
} |
||||
|
||||
_decodeEvents (tx, logs, contractName, compiledContracts) { |
||||
var eventABI = this._eventABI(contractName, compiledContracts) |
||||
// FIXME: support indexed events
|
||||
for (var i in logs) { |
||||
// [address, topics, mem]
|
||||
var log = logs[i] |
||||
var event |
||||
var decoded |
||||
|
||||
try { |
||||
var abi = eventABI[log.topics[0].replace('0x', '')] |
||||
event = abi.event |
||||
var types = abi.inputs.map(function (item) { |
||||
return item.type |
||||
}) |
||||
decoded = ethJSABI.rawDecode(types, new Buffer(log.data.replace('0x', ''), 'hex')) |
||||
decoded = ethJSABI.stringify(types, decoded) |
||||
} catch (e) { |
||||
decoded = log.data |
||||
} |
||||
if (!this.resolvedEvents[tx.hash]) { |
||||
this.resolvedEvents[tx.hash] = [] |
||||
} |
||||
this.resolvedEvents[tx.hash].push({ event: event, args: decoded }) |
||||
} |
||||
} |
||||
} |
||||
|
||||
module.exports = EventsDecoder |
Loading…
Reference in new issue