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Debugging OmniBridge Transactions


This page is mostly for application developers, if you sent tokens through the OmniBridge and would like to get the status whether the tokens were sent successfully or not, please use Bridge Explorer instead.

Firstly, the Foreign Arbitrary Message Bridge contract which is used by the OmniBridge, emits the UserRequestForAffirmation event as part of the a deposit request made by user (on the Ethereum side).

event UserRequestForAffirmation(bytes32 indexed messageId, bytes encodedData);

For example, this is the event in the OmniBridge transaction, and the topic 0x482515ce3d9494a37ce83f18b72b363449458435fafdd7a53ddea7460fe01b58
In the event definition and from the example, the Id of the AMB message is trackable as part of the event. The event from the example shows the message Id: 0x000500004ac82b41bd819dd871590b510316f2385cb196fb0000000000000402.
On the other side of the bridge, if the message was executed successfully the AMB contract emits the AffirmationCompleted event.

event AffirmationCompleted(
address indexed sender,
address indexed executor,
bytes32 indexed messageId,
bool status

Here is the event corresponding to the example
The topic of the event is 0xe194ef610f9150a2db4110b3db5116fd623175dca3528d7ae7046a1042f84fe7. And the message Id is represented as a separate topic in the event. That's why it is possible to use different ways to filter out the corresponding transaction if the message Id of the OmniBridge deposit is known (it always can be received from the deposit transaction). For example, you can use the BlockScout API for this: Example of the request to the BlockScout:

It will return the JSON with the transaction hash correlated to the emission of the event AffirmationCompleted with the message Id:

"message": "OK",
"result": [
"address": "0x75df5af045d91108662d8080fd1fefad6aa0bb59",
"blockNumber": "0xbc8133",
"data": "0x0000000000000000000000000000000000000000000000000000000000000001",
"gasPrice": "0x3b9aca00",
"gasUsed": "0x2d572",
"logIndex": "0x8",
"timeStamp": "0x5f7ab6dd",
"topics": [
"transactionHash": "0x092f1c8a02f305e5bfb671b923710cdd150c5b0e41df048c75b790538a25025b",
"transactionIndex": "0x5"
"status": "1"