feat: support "safe" param for eth_getBlockByNumber for 30 blocks

[snissn]

Related Issues

#12083

$ curl  -s -X POST localhost:1234/rpc/v1   -H "Content-Type: application/json"   -d '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockByNumber",
    "params":["safe", true],
    "id":1
}'  | jq -r '.result.number' | xargs printf "%d\n"
1714033

$ curl  -s -X POST localhost:1234/rpc/v1   -H "Content-Type: application/json"   -d '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockByNumber",
    "params":["latest", true],
    "id":1
}'  | jq -r '.result.number' | xargs printf "%d\n"
1714063

Proposed Changes

Additional Info

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[github-actions]

All checks have completed

❌ Failed Test / Test (itest-eth_legacy_transactions) (pull_request)

[rvagg]

Would be worth doing finalized as well in this and then we'd have the complete set, no?

[aarshkshah1992]

@snissn "finalised" should be very similar to the "safe" implementation no ? Best to just add it to this PR.

[rvagg]

there's a build.Finality for that btw

[snissn]

Thanks @rvagg @aarshkshah1992 !!

I will move the safeEpochDelay to a const in eth_types and will use build.Finality for the additional case and request a review again when that is ready

[snissn]

I've added support for 'finalized' and created a const for the safe delay with the suggested comment

$ curl  -s -X POST localhost:1234/rpc/v1   -H "Content-Type: application/json"   -d '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockByNumber",
    "params":["safe", true],
    "id":1
}'  | jq -r '.result.number' | xargs printf "%d\n"
1717680

$ curl  -s -X POST localhost:1234/rpc/v1   -H "Content-Type: application/json"   -d '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockByNumber",
    "params":["latest", true],
    "id":1
}'  | jq -r '.result.number' | xargs printf "%d\n"
1717710

$ curl  -s -X POST localhost:1234/rpc/v1   -H "Content-Type: application/json"   -d '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockByNumber",
    "params":["finalized", true],
    "id":1
}'  | jq -r '.result.number' | xargs printf "%d\n"
1716810

[rvagg]

Lack of tests is a bit of a bummer on this and there's not an easy slot for a new unit test - but if you could come up with an easy way to do it locally there then that would be great.

Here's an integration test that would exercise it, which is something at least, stick this in itests/eth_api_test.go under TestEthGetGenesis which has a EthGetBlockByNumber call so it's in a similar ballpark:

func TestEthBlockNumberAliases(t *testing.T) {
	blockTime := 2 * time.Millisecond
	kit.QuietMiningLogs()
	client, _, ens := kit.EnsembleMinimal(t, kit.MockProofs(), kit.ThroughRPC())
	ens.InterconnectAll().BeginMining(blockTime)
	ens.Start()

	build.Clock.Sleep(time.Second)

	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
	defer cancel()

	head := client.WaitTillChain(ctx, kit.HeightAtLeast(build.Finality+100))

	// latest should be head-1 (parents)
	latestEthBlk, err := client.EVM().EthGetBlockByNumber(ctx, "latest", true)
	require.NoError(t, err)
	diff := int64(latestEthBlk.Number) - int64(head.Height()-1)
	require.GreaterOrEqual(t, diff, int64(0))
	require.LessOrEqual(t, diff, int64(2))

	// safe should be latest-30
	safeEthBlk, err := client.EVM().EthGetBlockByNumber(ctx, "safe", true)
	require.NoError(t, err)
	diff = int64(latestEthBlk.Number-30) - int64(safeEthBlk.Number)
	require.GreaterOrEqual(t, diff, int64(0))
	require.LessOrEqual(t, diff, int64(2))

	// finalized should be Finality blocks behind latest
	finalityEthBlk, err := client.EVM().EthGetBlockByNumber(ctx, "finalized", true)
	require.NoError(t, err)
	diff = int64(latestEthBlk.Number) - int64(build.Finality) - int64(finalityEthBlk.Number)
	require.GreaterOrEqual(t, diff, int64(0))
	require.LessOrEqual(t, diff, int64(2))
}

maybe that could be made more concise; the awkwardness is in wanting to allow a fast moving chain to move on between calls, so we can't guarantee we'll hit it precisely, hence the 2 epochs

[snissn]

Thanks that test looks great and it feels a lot better that we have this test coverage with this PR! 84199c2