Problem: web3 getBlock api could return empty transactions

[yihuang]

System info: ethermint 0.7.2

Steps to reproduce:

We found in production that, eth_getBlockByNumber API can return empty transactions occasionally. Which causes issues in explorer and other clients.

Investigation shows that for the problematic block, the tx indexer fails to work at all.

$ curl localhost:26657/tx_search?query=%22ethereum_tx.ethereumTxHash=%270x0e46038e00945639488178aeee4af84f63c6a2229d3c0658e8a8582fb5e63c42%27%22
{
  "jsonrpc": "2.0",
  "id": -1,
  "result": {
    "txs": [],
    "total_count": "0"
  }
}

And the web3 API tries to call GetTxsByEthHash for each tx, and fails to find them.

The tx indexer can also lag behind block commit since it's running async.

Expected behavior: getBlock API should work all the time

Actual behavior: fails occasionally

Additional info:

Possible solution:

• don't rely on GetTxsByEthHash at all in eth_getBlockByNumber and similar apis, we can call BlockResults to get the information we need.
• Still need to investigate why tx indexer fails occationally.

[leejw51crypto]

does it happen to latest block only?

[yihuang]

does it happen to latest block only?

tendermint/tendermint#7312
it can also happen when tx indexer miss a whole block.

[JayT106]

Can we see the log of the node which might have the missing tx indexing?