> For the complete documentation index, see [llms.txt](https://docs.thehemera.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.thehemera.com/hemera-indexer/use-cases/opensea/trigger-and-function.md).

# Trigger and Function

The Opensea job is triggered when an Opensea-related transaction occurs or an event is produced. Specifically:

ref: [Opensea Event and Errors](https://docs.opensea.io/docs/seaport-events-and-errors)

* `OrderFulfilled`: When an order is successfully fulfilled

![Screenshot of Opensea](/files/rQjOIH35627cttMLda23)

```python
def parse_opensea_transaction_order_fulfilled_event(
        transaction: Transaction, contract_address: str, protocol_version: str = 1.6, fee_addresses: List[str] = []
) -> List[OpenseaLog]:
    results = []
    logs = transaction.receipt.logs
    for log in logs:
        if (
                log.topic0 == OPENSEA_EVENT_ABI_SIGNATURE_MAPPING["ORDER_FULFILLED_EVENT"]
                and log.address == contract_address
        ):
            opensea_transaction = decode_log(OPENSEA_EVENT_ABI_MAPPING["ORDER_FULFILLED_EVENT"], log)

            results.append(
                OpenseaLog(
                    orderHash="0x" + opensea_transaction["orderHash"].hex(),
                    offerer=opensea_transaction["offerer"],
                    zone=opensea_transaction["zone"],
                    recipient=opensea_transaction["recipient"],
                    offer=opensea_transaction["offer"],
                    consideration=opensea_transaction["consideration"],
                    block_timestamp=transaction.block_timestamp,
                    block_hash=transaction.block_hash,
                    block_number=transaction.block_number,
                    transaction_hash=transaction.hash,
                    log_index=log.log_index,
                    protocol_version=protocol_version,
                    fee_addresses=fee_addresses,
                )
            )

    return results
```

and the function to extract the data from the opensea event log:

```python
def transfer(self, opensea_logs: List[OpenseaLog]):
        for opensea_log in opensea_logs:
            yield OpenseaOrder(
                order_hash=opensea_log.orderHash,
                zone=opensea_log.zone,
                offerer=opensea_log.offerer,
                recipient=opensea_log.recipient,
                offer=opensea_log.offer,
                consideration=opensea_log.consideration,
                block_timestamp=opensea_log.block_timestamp,
                block_hash=opensea_log.block_hash,
                transaction_hash=opensea_log.transaction_hash,
                block_number=opensea_log.block_number,
                log_index=opensea_log.log_index,
                protocol_version=opensea_log.protocol_version,
            )
            offer = calculate_total_amount(opensea_log.offer)
            consideration = calculate_total_amount(opensea_log.consideration)
            fee = calculate_fee_amount(opensea_log.consideration, opensea_log.fee_addresses)

            opensea_transaciton_type = get_opensea_transaction_type(opensea_log.offer, opensea_log.consideration)
            if opensea_log.offerer == opensea_log.recipient:
                continue
            yield AddressOpenseaTransaction(
                address=opensea_log.offerer,
                related_address=opensea_log.recipient,
                is_offer=True,
                transaction_type=opensea_transaciton_type.value,
                order_hash=opensea_log.orderHash,
                zone=opensea_log.zone,
                offer=offer,
                consideration=consideration,
                fee=fee,
                transaction_hash=opensea_log.transaction_hash,
                block_number=opensea_log.block_number,
                log_index=opensea_log.log_index,
                block_timestamp=opensea_log.block_timestamp,
                block_hash=opensea_log.block_hash,
                protocol_version=opensea_log.protocol_version,
            )
            yield AddressOpenseaTransaction(
                address=opensea_log.recipient,
                related_address=opensea_log.offerer,
                is_offer=False,
                transaction_type=(
                    1 - opensea_transaciton_type.value
                    if opensea_transaciton_type.value <= 1
                    else opensea_transaciton_type.value
                ),
                order_hash=opensea_log.orderHash,
                zone=opensea_log.zone,
                offer=offer,
                consideration=consideration,
                fee=fee,
                transaction_hash=opensea_log.transaction_hash,
                block_number=opensea_log.block_number,
                log_index=opensea_log.log_index,
                block_timestamp=opensea_log.block_timestamp,
                block_hash=opensea_log.block_hash,
                protocol_version=opensea_log.protocol_version,
            )
```


---

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