I'm having trouble getting a history of events. I'm unsure if I am misunderstanding how events work, if I'm coding wrong, or if it has anything to do with the recent Ethereum attacks slowing down the network. My workflow is that I have a single contract deployed called "KnowledgeExchangeManager" and it in turn creates "KnowledgeExchange" contracts when you submit a question. When a KnowledgeExchange contract is created it also creates a KnowledgeExchangeEvent so that I can later look up the contracts that have been generated.
Contract:
pragma solidity ^0.4.2;
contract KnowledgeExchangeManager {
address owner;
event KnowledgeExchangeEvent(
address indexed _from,
address _exchange
);
function KnowledgeExchangeManager() {
owner = msg.sender;
}
function submitQuestion(string _title, string _body) payable {
KnowledgeExchange exchangeContract = new KnowledgeExchange(msg.sender, _title, _body);
KnowledgeExchangeEvent(msg.sender, exchangeContract);
}
function kill() {
if (msg.sender == owner) selfdestruct(owner);
}
}
contract KnowledgeExchange {
event BountyClaimed(
address indexed _owner
);
struct Question {
address owner;
string title;
string body;
}
struct Answer {
address owner;
string body;
}
Question question;
Answer answer;
bool public answered;
function KnowledgeExchange(address questioner, string _title, string _body) payable {
question = Question(questioner, _title, _body);
answered = false;
}
function getQuestionDetails() returns (address, string, string, uint) {
return (question.owner, question.title, question.body, this.balance);
}
function submitAnswer(string _body) {
bool success = msg.sender.send(this.balance);
if (!success) {
throw;
}
answered = true;
answer = Answer(msg.sender, _body);
BountyClaimed(msg.sender);
}
function getAnswerDetails() returns (address, string) {
return (answer.owner, answer.body);
}
function getBounty() returns (uint256) {
return this.balance;
}
function kill() {
if (msg.sender == question.owner) selfdestruct(question.owner);
}
}
Javascript UI:
var accounts;
var account;
var knowledgeManager;
function refreshQuestions() {
console.log("Refreshing Questions...");
var exchangeEvent = knowledgeManager.KnowledgeExchangeEvent({fromBlock: 0, toBlock: 'latest'});
exchangeEvent.watch(function(error, events) {
console.log("Got Questions.");
if (!error) {
console.log(events);
} else {
console.log(error);
}
exchangeEvent.stopWatching();
});
};
function submitQuestion() {
knowledgeManager.submitQuestion("Test Question", "Lorem ipsum dolor amet", {from: account, gas: 900000}, function(error, txId) {
if (error) {
console.log(error);
} else {
console.log(txId);
}
});
};
window.onload = function() {
console.log("Loading App");
web3.eth.getAccounts(function(err, accs) {
if (err != null) {
alert("There was an error fetching your accounts.");
return;
}
if (accs.length == 0) {
alert("Couldn't get any accounts! Make sure your Ethereum client is configured correctly.");
return;
}
accounts = accs;
account = accounts[0];
knowledgeManager = web3.eth.contract(JSON.parse('[ { "constant": false, "inputs": [ { "name": "_title", "type": "string" }, { "name": "_body", "type": "string" } ], "name": "submitQuestion", "outputs": [], "payable": true, "type": "function" }, { "constant": false, "inputs": [], "name": "kill", "outputs": [], "payable": false, "type": "function" }, { "inputs": [], "type": "constructor" }, { "anonymous": false, "inputs": [ { "indexed": true, "name": "_from", "type": "address" }, { "indexed": false, "name": "_exchange", "type": "address" } ], "name": "KnowledgeExchangeEvent", "type": "event" } ]'))
.at("0xb52e407F7Feb3C2D14b1721584dd3ea34166C716");
refreshQuestions();
});
}
I had assumed the javascript should be fetching all events when the page loads, but it rarely ever does. If it does work it will be after quite a while (5 min). I have tested my application in both Chrome with Metamask running and in Mist Browser. I'm using the morden test network.
