paginate eth logs

[ayrat555]

resolves #2353

Changelog

• paginate eth logs

[coveralls]

Pull Request Test Coverage Report for Build eac09c44-7f16-48e9-ab6b-8a74f692b56a

• 11 of 94 (11.7%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-1.3%) to 79.63%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/eth_controller.ex	2	3	66.67%
apps/explorer/lib/explorer/eth_rpc.ex	0	82	0.0%

Totals
Change from base Build e8dae500-635c-4255-b6c3-0243d5e67b8e:	-1.3%
Covered Lines:	5129
Relevant Lines:	6441

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💛 - Coveralls

[pasqu4le]

LGTM, only a couple nitpick suggestions

[vbaranov]

1. It is unclear from the docs is the pagination option is a part of params or pagination params are on the same level as params. If they are a part of params, they should be included in the example
2. If I try to request this endpoint w/out pagination api endpoint responds to me with the number much less then 1000 logs entries. Try transfer method: 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef
3. It is unclear should use all 3 params of pagination or could use only one to paginate
4. which include parameters from the last log received from the previous request. - this is a wrong statement because the previous call includes neither block_number nor transaction_index, log_index. All of them have other names in the response of previous call

[ayrat555]

@vbaranov

1. I added an example with paging options.
2. Did you include fromBlock, toBlock params?
   try curl -v -X POST --data '{"id": 0, "jsonrpc": "2.0", "method": "eth_getLogs", "params": [{"address": "0xc78Be425090Dbd437532594D12267C5934Cc6c6f", "fromBlock": "earliest", "toBlock": "latest", "topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]}]}' "http://localhost:4000/api/eth_rpc"
   response contains exactly 1_000 items
3. I updated a note
4. I changed param names to macth json rpc spec

[vbaranov]

@ayrat555

Did you include fromBlock, toBlock params?

Yes, that is what the issue.

1 - 4 ✔️. One more thing in order to improve pagination UX: is it possible (if no performance concerns) to reorder response in that way, that all three pagination's params would be together? Therefore, the user can copy them in one click. Because currently, a user should copy every parameter to collect them all to make a request for the next page.

[ayrat555]

@vbaranov it's possible. but do you think users will use pagination params not programmatically but by hand?

[vbaranov]

@vbaranov it's possible. but do you think users will use pagination params not programmatically but by hand?

Got your point. It makes sense, that programmatic control is prevalent for API. If API users will have this feature request, let's implement it. But for now, let's leave it as is.