This PR separates ENGINE from Ethbackend. It makes it so:
1) EthBackend not a god class
2) We can abstract away engine API so that we can make it CL-like and
enable Consensus-Execution driven design
3) Objective is Json-RPC -> Engine Consensus Module -> Execution module.
- breaks dependency from staged_sync to package with block_reader
implementation
- breaks dependency from snap_sync to package with block_reader
implementation
- breaks dependency from mining to txpool implementation
attempt to address next issue:
> when I'm having a lot of websocket connections the node is freezing
and then it needs like 10 mins to sync. Then if I keep pushing requests
it falls out of sync all the time
When testing with `Bor` consensus turned on I discovered that
`SendRawTransaction` returns a 0x000... hash when transactions are
submitted during block transitions. This turns out to be spurious in the
sense that the transaction insertion is successful.
The cause is that `ReadCurrentBlockNumber` returns a nil block number.
This in turn is caused by the following: In `accessors_chain.go` there
are two methods: `WriteHeader` and `WriteHeadHeaderHash` when the first
is called the block number is written for the header. The second writes
the header has, but there is no guarantee when it does that the head
header will have been written yet. In fact it seems to happen sometime
later.
The problem for `SendRawTransation` is that it begins a transaction
after inserting into the txpool. And depending on timing this
transaction may see only the `WriteHeadHeaderHash` insertion, and hence
can't read the block number.
I have mitigated this by opening the db transaction before calling the
tx pool insertion, meaning that it is more likely to have a clean view
of the DB.
I have also moved the chain id check earlier in the code - as I think
that if this is invalid the method should not try to insert transactions
in the first place.
The `ReadCurrentBlockNumber` is only used to produce a log message - so
I've changed this to not fail the whole function but to just log an
unknown sender. Which means that the hash is still returned to the
sender after a successful txpool insertion
- allow store non-canonical blocks/senders
- optimize re-org: don't update/delete most of data
- allow mark chain as `Bad` - will be not visible by eth_getBlockByHash,
but can read if have hash+num
- always RLock all snapshots - to guarantee consistency
- introduce class View (analog of RoTx and MakeContext)
- move read methods to View object
- View object will be managed by temporal_tx
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Co-authored-by: Alex Sharp <alexsharp@Alexs-MacBook-Pro-2.local>
