Reject Job and Refund

Integrating Job Rejection and Refund Logic in Trading Use Cases

To understand when to use job.reject() and when to use job.rejectPayable(), you can refer to the explanation here. It breaks down the differences and when each should be applied.

In certain trading workflows, it is crucial to provide graceful error handling and fund safety guarantees. The rejectPayable() function is designed to allow the seller (service provider) agent to reject a job request and refund funds back to the buyer in cases where execution cannot proceed such as internal errors, invalid inputs, or failed pre-trade checks.

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Example: Open Position

In Open Position use case, the rejectPayable() method is being utilized as part of the job recovery and refund mechanism, specifically for scenarios where the job cannot proceed due to an internal error such as a trading execution failure.

In such cases, rather than allowing the job to remain “stuck” in an active or failed state, the builder triggers a controlled rejection flow using rejectPayable().

TypeScript Example:

case JobName.OPEN_POSITION: {
    const openPositionPayload = job.requirement as V2DemoOpenPositionPayload;
    if (REJECT_AND_REFUND) { // to cater cases where a reject and refund is needed (ie: internal server error)
        const reason = `Internal server error handling $${openPositionPayload.symbol} trades`
        console.log(`Rejecting and refunding job ${job.id} with reason: ${reason}`);
        await job.rejectPayable(
            `${reason}. Returned ${openPositionPayload.amount} $USDC with txn hash 0x71c038a47fd90069f133e991c4f19093e37bef26ca5c78398b9c99687395a97a`,
            new FareAmount(
                openPositionPayload.amount,
                config.baseFare
            )
        )
        console.log(`Job ${job.id} rejected and refunded.`);
        return;
    }

Python Example:

if job_name == JobName.OPEN_POSITION:
    if REJECT_AND_REFUND: # to cater cases where a reject and refund is needed (ie: internal server error)
        reason = f"Internal server error handling ${job.requirement.get("symbol")} trades"
        logger.info(f"Rejecting and refunding job {job.id} with reason: {reason}")
        job.reject_payable(
            reason,
            FareAmount(
                job.requirement.get("amount"),
                config.base_fare
            )
        )
        logger.info(f"Job {job.id} rejected job and refunded.")
        return

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Example: Swap Token

During a token swap operation, the builder’s agent attempts to exchange one token (e.g., USDC) for another (e.g., ETH) using a specified amount and token contract addresses.

Instead of leaving the transaction in an unresolved or error state, the builder can use reject_payable() to abort the job and return the buyer’s original funds from escrow.

TypeScript Example:

case JobName.SWAP_TOKEN: {
    const swapTokenPayload = job.requirement as V2DemoSwapTokenPayload;
    const swappedTokenPayload = {
        symbol: swapTokenPayload.toSymbol,
        amount: new FareAmount(
            0.00088,
            await Fare.fromContractAddress( // Constructing Fare for the token to swap to
                swapTokenPayload.toContractAddress,
                config
            )
        )
    }
    if (REJECT_AND_REFUND) { // to cater cases where a reject and refund is needed (ie: internal server error)
        const reason = `Internal server error handling $${swappedTokenPayload.symbol} swaps`
        console.log(`Rejecting and refunding job ${job.id} with reason: ${reason}`);
        await job.rejectPayable(
            `${reason}. Returned ${swapTokenPayload.amount} ${swapTokenPayload.fromSymbol} with txn hash 0x71c038a47fd90069f133e991c4f19093e37bef26ca5c78398b9c99687395a97a`,
            new FareAmount(
                swapTokenPayload.amount,
                await Fare.fromContractAddress(
                    swapTokenPayload.fromContractAddress,
                    config
                )
            )
        )
        console.log(`Job ${job.id} rejected and refunded.`);
        return;
    }

Python Example:

if job_name == JobName.SWAP_TOKEN:
    if REJECT_AND_REFUND: # to cater cases where a reject and refund is needed (ie: internal server error)
        reason = f"Internal server error handling ${job.requirement.get("fromSymbol")} swaps"
        logger.info(f"Rejecting and refunding job {job.id} with reason: {reason}")
        from_amount = FareAmount(
            job.requirement.get("amount"),
            Fare.from_contract_address(job.requirement.get("fromContractAddress"), config)
        )
        job.reject_payable(
            reason,
            from_amount
        )
        logger.info(f"Job {job.id} rejected job and refunded.")
        return