fix: return 32-byte block hash from eth_getFilterChanges to ensure EVM compatibility

[romangzz]

Description:

Ensure eth_getFilterChanges returns a 32-byte block hash to match Ethereum's expectations.

• Truncate Hedera's 48-byte block hash (from mirror node record files) to 32 bytes
• Aligns with Ethereum's EVM compatibility requirements
• Enables valid usage of returned hashes with eth_getBlockByHash
• Fixes compatibility issue affecting downstream clients/tools

Notes for reviewer:

Previously, eth_getFilterChanges returned 48-byte block hashes, causing eth_getBlockByHash to fail with a parameter validation error. This PR ensures that only the first 32 bytes are returned, complying with Ethereum's JSON-RPC spec.

Example of uncorrected output response:

{
    "result": [
      "0x3c08bbbee74d287b1dcd3f0ca6d1d2cb92c90883c4acf9747de9f3f3162ad25b999fc7e86699f60f2a3fb3ed9a646c6b"
    ],
    "jsonrpc": "2.0",
    "id": 1
}

Example of corrected output response:

{
    "result": [
        "0x3c08bbbee74d287b1dcd3f0ca6d1d2cb92c90883c4acf9747de9f3f3162ad25b"
    ],
    "jsonrpc": "2.0",
    "id": 1
}

Documentation:

According to the Ethereum JSON-RPC Specification, the blockHash must match the following pattern: ^0x[0-9a-f]{64}$, which represents a 32-byte Ethereum block hash.

Fixes #3975.

Checklist

• Documented (Code comments, README, etc.)
• Tested (unit, integration, etc.)

[lfdt-bot]

🎉 Snyk checks have passed. No issues have been found so far.

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[quiet-node]

Hey @romangzz, thanks much for the PR great catch indeed! Could you kindly include some links to documentation, if any, supporting this update like from official Ethereum's JSON-RPC spec or whatnot? It’ll help provide context for future reference. If possible, please add the links to the PR description for better clarity.

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...vices/ethService/ethFilterService/FilterService.ts	50.00%	1 Missing ⚠️

@@           Coverage Diff           @@
##             main    #3863   +/-   ##
=======================================
  Coverage        ?   50.66%           
=======================================
  Files           ?       83           
  Lines           ?     4767           
  Branches        ?      972           
=======================================
  Hits            ?     2415           
  Misses          ?     1990           
  Partials        ?      362           

Files with missing lines	Coverage Δ
...vices/ethService/ethFilterService/FilterService.ts	17.50% <50.00%> (ø)

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[quiet-node]

Hey @romangzz are there any new updates on this PR?

[romangzz]

Hey @romangzz, thanks much for the PR great catch indeed! Could you kindly include some links to documentation, if any, supporting this update like from official Ethereum's JSON-RPC spec or whatnot? It’ll help provide context for future reference. If possible, please add the links to the PR description for better clarity.

Hey @quiet-node, sorry for the delay. I've just updated the PR description to include the Ethereum JSON-RPC specification that outlines the expected format of the response.

[quiet-node]

Hey @romangzz, thanks much for the PR great catch indeed! Could you kindly include some links to documentation, if any, supporting this update like from official Ethereum's JSON-RPC spec or whatnot? It’ll help provide context for future reference. If possible, please add the links to the PR description for better clarity.

Hey @quiet-node, sorry for the delay. I've just updated the PR description to include the Ethereum JSON-RPC specification that outlines the expected format of the response.

Hey @romangzz thanks much! The team will review soon! Seems like the tests are failing please resolve them when you have a chance.

[acuarica]

Hi @romangzz, nice catch indeed!

Please fix the failing test (it's failing because it's actually checking for 48-byte hashes)

hiero-json-rpc-relay/packages/server/tests/acceptance/rpc_batch3.spec.ts

Lines 1085 to 1103 in 8ef3c38

	it('@release should be able to call eth_getFilterChanges for NEW_BLOCK filter', async function () {
	const filterId = await relay.call(RelayCalls.ETH_ENDPOINTS.ETH_NEW_BLOCK_FILTER, [], requestId);
	await new Promise((r) => setTimeout(r, 4000));
	const result = await relay.call(RelayCalls.ETH_ENDPOINTS.ETH_GET_FILTER_CHANGES, [filterId], requestId);
	expect(result).to.exist;
	expect(result.length).to.gt(0, 'returns the latest block hashes');
	result.forEach((hash: string) => {
	expect(RelayAssertions.validateHash(hash, 96)).to.eq(true);
	});
	await new Promise((r) => setTimeout(r, 2000));
	const result2 = await relay.call(RelayCalls.ETH_ENDPOINTS.ETH_GET_FILTER_CHANGES, [filterId], requestId);
	expect(result2).to.exist;
	expect(result2.length).to.be.greaterThanOrEqual(1);
	expect(RelayAssertions.validateHash(result2[0], 96)).to.eq(true);
	});
	});

[quiet-node]

Nice work @romangzz but unit test CI is still failing. Please resolve when you have a chance

[acuarica]

There was an issue with the test

[acuarica]

@romangzz we just fix an issue on main that was making CI to fail. Please rebase this branch.

[romangzz]

Hey @acuarica, I just rebased the branch.

[quiet-node]

LGTM thanks much for the effort!

[acuarica]

Hi @romangzz, merged! thanks for your contribution!