Prevent timeout for getting Ethereum event logs

[shun-tak]

The following code fails with a timeout when the number of blocks to get is too big

cordage/cross-chain-atomic-swap-cordapp/src/main/kotlin/jp/co/layerx/cordage/crosschainatomicswap/flow/EventWatchFlow.kt

Lines 78 to 82 in 4821768

	val filter = EthFilter(DefaultBlockParameter.valueOf(watcherState.fromBlockNumber),
	DefaultBlockParameter.valueOf(watcherState.toBlockNumber),
	watcherState.targetContractAddress)
	val ethLogs = web3.ethGetLogs(filter).send()

Solution

• be able to choose fromBlockNumber when starting StartEventWatchFlow
• limit number of blocks to watch in one time