How long can events be retrieved for?

Question

Does anyone know how long events can be retrieved for?

I have events on the Kovan contract at 0x86e5b6d7648b8b994886aeb98e2b4770675e608d and it appears I can no longer retrieve events older than 14 days?

The code I'm using is as follows. Both get and watch are not retrieving events that are older than 14 days. I don't have anything in between today and 14 days, so I don't know if it stopped retrieving events older than a few days, or if there's a limit.

Thanks in advance for any help.

UPDATE: Ok, it seems the issue was that Parity had a different meaning of "fully sync'd" than I thought. If you see a line such as

2017-11-02 15:31:11 #4098136 23/25 peers 301 MiB chain 83 MiB db 0 bytes queue 10 MiB sync RPC: 1 conn, 3 req/s, 142 µs

in the console output, then what it means is that Parity hasn't fully downloaded all the logs yet, and it has only downloaded the logs for block 4098136 (in this case), even though you see

2017-11-02 15:31:13 Imported #4569744 1c13…0e14 (0 txs, 0.00 Mgas, 0.81 ms, 0.57 KiB)

let ContractAddr = "0x86E5b6D7648b8B994886aeB98E2B4770675e608D"; // on Kovan

    optionsShout = {
      fromBlock: 4289879,
      toBlock: 'latest',
      address: ContractAddr,
      topics: [web3.sha3('__Shout(string)')]
    }

    let filter, w;

    function getLogs() {
      var filter = web3.eth.filter(optionsShout);
      console.log("getLogs...");
      filter.get(function(error, event) {
        if (!error) {
          console.log("Event: " + event);
        } else
        {
          console.log("Error: " + error);
        }
      })
    }

    function startFilter() {
      console.log("Starting filter");
      filter = web3.eth.filter(optionsShout);

      filter.watch(function(error, event) {
        if (!error) {
          if (event.blockNumber > optionsShout.fromBlock) {
            optionsShout.fromBlock = event.blockNumber;
            displayEvent("event1", event);
          }
        } else
        {
          console.log("Error: "+error);

        }
      })
    }

Answer 1

There are a few possible problems here:

1) The node you're connected to may not have old events, or may have a policy against letting you retrieve them.

2) The range of logs you're requesting may be too wide. This can cause nodes to time out. Try finding a block where your contract has events and specifying just that block number as the range. If that shows your logs, try increasing the range until you find where the practical limit is, and fetch in batches limited to that range.

3) If you're using metamask, there seems to be some buggy behaviour around log fetching. After making sure you're on the right network, try closing all open Chrome windows then reopening it.

Answer 2

It doesn't really sound like you need a filter, just grab all the events:

let transferEvent = MyContract.Event({}, {fromBlock: 0, toBlock: 'latest'})
transferEvent.get((error, logs) => {
  // we have the logs, now print them
  logs.forEach(log => console.log(log.args))
  }