feat: eth_get_balance rpc endpoint

[zachdaniel]

Resolves #2015

Example:

curl -H "Content-Type: application/json" -X POST --data '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xc94770007dda54cF92009BFF0dE90c06F603a09f", "latest"],"id":1}' <explorer>/api/eth_rpc

Changelog

Enhancements

This mimics the ethGetBalance json rpc. The only issue is that we don't currently create balances for accounts that have a balance at the genesis block. A ticket for doing that is here: #2080

• I added an entry to CHANGELOG.md with this PR
• If I added new functionality, I added tests covering it.
• If I fixed a bug, I added a regression test to prevent the bug from silently reappearing again.
• I checked whether I should update the docs and did so if necessary

[coveralls]

Pull Request Test Coverage Report for Build ee4ba479-d2ac-4a3c-95e5-1e27f866e37d

• 31 of 60 (51.67%) changed or added relevant lines in 8 files are covered.
• 57 unchanged lines in 13 files lost coverage.
• Overall coverage decreased (-1.2%) to 79.805%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
apps/block_scout_web/lib/block_scout_web/views/api/rpc/address_view.ex	0	1	0.0%
apps/block_scout_web/lib/block_scout_web/views/api/rpc/eth_rpc_view.ex	7	8	87.5%
apps/explorer/lib/explorer/chain/wei.ex	0	2	0.0%
apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/eth_controller.ex	21	26	80.77%
apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/address_controller.ex	0	10	0.0%
apps/explorer/lib/explorer/chain.ex	0	10	0.0%

Files with Coverage Reduction	New Missed Lines	%
apps/indexer/lib/indexer/transform/addresses.ex	1	79.17%
apps/block_scout_web/lib/block_scout_web/channels/exchange_rate_channel.ex	1	50.0%
apps/ethereum_jsonrpc/test/support/ethereum_jsonrpc/case/parity/http_websocket.ex	1	0.0%
apps/block_scout_web/lib/block_scout_web/controllers/address_token_controller.ex	2	76.47%
apps/block_scout_web/lib/block_scout_web/views/address_transaction_view.ex	2	50.0%
apps/block_scout_web/lib/block_scout_web/controllers/address_token_transfer_controller.ex	2	90.48%
apps/indexer/lib/indexer/block/fetcher.ex	3	84.0%
apps/ethereum_jsonrpc/test/support/ethereum_jsonrpc/web_socket/case/parity.ex	4	0.0%
apps/block_scout_web/lib/block_scout_web/channels/address_channel.ex	5	35.29%
apps/ethereum_jsonrpc/lib/ethereum_jsonrpc/web_socket/web_socket_client.ex	6	76.25%

Totals
Change from base Build 7c94713a-f520-4933-913d-641991a525ac:	-1.2%
Covered Lines:	4837
Relevant Lines:	6061

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💛 - Coveralls

[pasqu4le]

I'm not sure about the query that get_balance_as_of_block(address, :earliest) executes.

[pasqu4le]

Shouldn't this get the first known coin_balance for the address instead of the one at block 0?

This would fail for addresses whose first coin_balance is not at block 0, is this the intended behavior?

[ayrat555]

👍

[zachdaniel]

As far as I know, the "earliest" block does actually mean the genesis block. When I tried this endpoint out I couldn't get any address to respond w/ a non-zero balance on POA with the exception of the master of ceremony, implying that it is just talking about the first block.

[pasqu4le]

Ok if that's the case then there are no problems

[vbaranov]

@zachdaniel could you please drop a line in the PR description how to call this API endpoint?