Missing Synthetic Logs for CRYPTOTRANSFER initiated by another smart contract

[ted-yeh-vc]

Description

Here is a transfer of an HTS token where the log is emitted (by calling eth_getTransactionReceipt)
https://hashscan.io/mainnet/transaction/1718615133.322411003

Here is a transfer of an HTS token where the log is not emitted (calling eth_getTransactionReceipt returns an empty logs:[] field)
https://hashscan.io/mainnet/transaction/1719939759.390625006

If we were to look at the account involved in the transactions above (https://hashscan.io/mainnet/account/0.0.1142) and we filter by CRYPTOTRANSFERs involving the USDC token (https://hashscan.io/mainnet/token/0.0.456858),

we can find 14 transactions using the mirror node (GET /api/v1/transactions)

+-------------------+---------------------------+----------------------------------+-------------+--------------------+--------------------------------------------------------------+
| Consensus Time    | Timestamp                 | Transaction ID                   | Amount      | Found using relay  | Hashscan                                                     |
+-------------------+---------------------------+----------------------------------+-------------+--------------------+--------------------------------------------------------------+
| 1718615133.322411 | 2024-06-17T03:05:33-06:00 | 0.0.1142-1718615118-649398668    | 910507      | yes                | https://hashscan.io/mainnet/transaction/1718615133.322411003 |
| 1719939713.971043 | 2024-07-02T11:01:53-06:00 | 0.0.1055166-1719939703-963875922 | 2500000000  | yes                | https://hashscan.io/mainnet/transaction/1719939713.971042604 |
| 1719939759.390625 | 2024-07-02T11:02:39-06:00 | 0.0.1142-1719939746-108341164    | -2500910507 | no                 | https://hashscan.io/mainnet/transaction/1719939759.390625006 |
| 1722611485.493561 | 2024-08-02T09:11:25-06:00 | 0.0.1055166-1722611474-820259951 | 5560000000  | yes                | https://hashscan.io/mainnet/transaction/1722611485.493561003 |
| 1725040591.048449 | 2024-08-30T11:56:31-06:00 | 0.0.1142-1725040578-542090317    | -5560000000 | no                 | https://hashscan.io/mainnet/transaction/1725040591.048449006 |
| 1728572921.126551 | 2024-10-10T09:08:41-06:00 | 0.0.1142-1728572906-600505512    | 548175267   | yes                | https://hashscan.io/mainnet/transaction/1728572921.126551000 |
| 1731778794.676574 | 2024-11-16T10:39:54-07:00 | 0.0.1142-1731778780-544248843    | -492720371  | yes                | https://hashscan.io/mainnet/transaction/1731778794.676573449 |
| 1733161187.159266 | 2024-12-02T10:39:47-07:00 | 0.0.1142-1733161175-642389744    | 2496776839  | no                 | https://hashscan.io/mainnet/transaction/1733161187.159266003 |
| 1733408148.596359 | 2024-12-05T07:15:48-07:00 | 0.0.1142-1733408135-630249835    | -600000000  | no                 | https://hashscan.io/mainnet/transaction/1733408148.596359003 |
| 1734014534.596779 | 2024-12-12T07:42:14-07:00 | 0.0.1142-1734014522-621639492    | 2366428717  | no                 | https://hashscan.io/mainnet/transaction/1734014534.596779001 |
| 1735919476.561095 | 2025-01-03T08:51:16-07:00 | 0.0.1142-1735919462-730386058    | -875000000  | yes                | https://hashscan.io/mainnet/transaction/1735919476.561095000 |
| 1735919716.706294 | 2025-01-03T08:55:16-07:00 | 0.0.1142-1735919703-841779418    | -313000000  | yes                | https://hashscan.io/mainnet/transaction/1735919716.706294000 |
| 1740814994.812307 | 2025-03-01T00:43:14-07:00 | 0.0.1142-1740814985-663330866    | 1557412236  | no                 | https://hashscan.io/mainnet/transaction/1740814994.812307001 |
| 1740936081.111070 | 2025-03-02T10:21:21-07:00 | 0.0.1142-1740936073-664158289    | 1066011127  | no                 | https://hashscan.io/mainnet/transaction/1740936081.111070001 |
+-------------------+---------------------------+----------------------------------+-------------+--------------------+--------------------------------------------------------------+

2025/03/28 10:55:08     Mirror Node Transfers: 14

and 7 using the relay

+---------------------------+----------------+------------+--------------------------------------------------------------------+
| Timestamp                 | Consensus Time | Value      | Transaction ID                                                     |
+---------------------------+----------------+------------+--------------------------------------------------------------------+
| 2024-06-17T03:05:32-06:00 | 1718615132.00  | 910507     | 0xf700ce9f9ba9c2bcb049980323fe1724ea5f65837c6e4d196a3b85655fc80dcb |
| 2024-07-02T11:01:52-06:00 | 1719939712.00  | 2500000000 | 0xfd988861653f97b334e2f81a5c70a705eb0a39664ac35d767105c0caa234f0bf |
| 2024-08-02T09:11:24-06:00 | 1722611484.00  | 5560000000 | 0xd8f770b3ba619e13b213422819b4badd39e25ce85ee645922182377bbe84652c |
| 2024-10-10T09:08:40-06:00 | 1728572920.00  | 548175267  | 0x022e6e63fe57de9a66c743b46a53d022302b6318fe803a4a0473d3e5a52f6d01 |
| 2024-11-16T10:39:54-07:00 | 1731778794.00  | -492720371 | 0xdb2c71a6ec000bfcfbb2f34281fd4ad33856d26346aad466e59c46c361901404 |
| 2025-01-03T08:51:16-07:00 | 1735919476.00  | -875000000 | 0x08fd4cc5cb6ad7ee5a0df8088acb666c07c95cd11237b2108db7d80b6ce0735a |
| 2025-01-03T08:55:16-07:00 | 1735919716.00  | -313000000 | 0x759e15f759f7bfce53f7645745db51ab3f31f384635d365167542fe66351ec27 |
+---------------------------+----------------+------------+--------------------------------------------------------------------+

2025/03/28 10:55:07        EVM Event Transfers: 7

Steps to reproduce

1. get list of transactions using the mirror node for a account <-> token pair
2. get list of transactions using the relay by iterating over all blocks and looking for logs emitted from the token contract involving the account in question
3. find that relay returns much few transfer logs than the mirror node.

Additional context

No response

Hedera network

mainnet

Version

v0.66.0

Operating system

None

[natanasow]

Hey, @ted-yeh-vc, could you give us a little more context on why you need to get child transaction's receipt? What's your use case?

In Hedera, there is a concept where each nested contract call is interpreted as a child transaction. That's your case. Let's dive deep into https://hashscan.io/mainnet/transaction/1734014534.596779001.

• the transaction you want to fetch via eth_getTransactionReceipt is a child transaction - img #1
• here is the parent one - img #2
• we can get the parent transaction hash - img #3
• then we can query the relay and the right logs are being returned as expected img #4

If we explore transactions you provided in Hashscan, we can observe that there are no emitted events, which is actually right. All events are "collected" and returned in the parent transaction (the top-level call) as it's in other EVM chains. The misunderstanding here comes from the ability to query child transaction and that they have hash IMO which is not possible in other EVM chains.

The correct way to get eth_getTransactionReceipt and logs is by sending the parent transaction hash instead of child hashes.

PS: Meanwhile, I'm researching whether it is possible to return a child transaction with aligned logs to that internal call.

[kasey-alusi-vcc]

Hi @natanasow , thank you for digging into this! I work with Ted at Validation Cloud as well. Based on our understanding of the issue, I think the parent/child distinction is unrelated.

Effectively the system we are using parses data out of EVM smart contracts in the following steps:

1. Examine each block for events emitted from a particular address (in the case of ERC20 contracts, the token address)
2. If the address of the contract emitting events matches, parse and index the event

Note: All of this is done using the json-rpc-relay, the mirror node data that Ted shared above is just for investigation purposes.

In the case of ERC20 smart contracts, on most chains, if you do the above steps filtering for the single ERC20 smart contract address, you will have a list of all transfers for a token.

What we’ve found on hedera is that there are at least two addresses that can transfer a token:

1. The synthetic contract of the token itself (example of USDC: [0x000000000000000000000000000000000006f89a](https://hashscan.io/mainnet/token/0.0.456858)
2. Hedera Token Service Smart Contract: [0x0000000000000000000000000000000000000167](https://hashscan.io/mainnet/contract/0.0.359?pr=1)

Since standard ERC20 tokens only have to look at one address, the transfers that are done through the token service are missed.

An example of a transfer done through the USDC synthetic contract that is correctly found by looking at the USDC address:

https://hashscan.io/mainnet/transaction/1718615133.322411003

An example of a transfer event through the Hedera Token Service Smart Contract which is not trackable through the USDC synthetic contract:

https://hashscan.io/mainnet/transaction/1719939759.390625006

We would be happy to jump on a call if this would be easier to chat through live.

From our point of view, if one of the goals of the json-rpc relay is to support these ERC20 like a native EVM chain, we'd be able to get all events for the token using the address of that token only (no HTSSC).

[natanasow]

@kasey-alusi-vcc Thanks for the detailed explanation.

We're already working on that, and if we need more information, we can jump on a call 🙂. Will keep you guys up-to-date on the progress.

[ted-yeh-vc]

We're already working on that, and if we need more information, we can jump on a call 🙂. Will keep you guys up-to-date on the progress.

That's great to hear. Is there a HIP or Issue/Epic that we can follow for updates?

[natanasow]

We triaged your issue, so you can track the progress here.

[natanasow]

Waiting for a response from the MN team. The issue is here hiero-ledger/hiero-mirror-node#10829.