nick-doc/02 - Data Models/Payment.md

title, tags, aliases

title	tags	aliases
Payment	data-model mongoose	Payment Record Escrow IPayment

Payment

Records every monetary movement in the marketplace: buyer pay-ins, seller payouts, and refunds. Designed around the SHKeeper crypto payment gateway with explicit fields for blockchain network, transaction hash, escrow state, and provider invoice ids. The provider and direction discriminators let one collection hold all four flow types (incoming buyer payment, outgoing seller payout, refund, and "other" provider integrations).

[!note] Source backend/src/models/Payment.ts:3 — schema definition backend/src/models/Payment.ts:257 — model export (default export)

[!warning] Mixed types purchaseRequestId, sellerOfferId, and sellerId use Schema.Types.Mixed. They are usually ObjectIds, but the template-checkout flow passes string ids that do not yet exist in the database, so the schema accepts both.

Schema

Field	Type	Required	Default	Validation	Index	Description
purchaseRequestId	Mixed (ObjectId or String)	yes	—	—	yes (compound, partial)	Linked PurchaseRequest id (or template id).
sellerOfferId	Mixed (ObjectId or String)	yes	—	—	—	Linked SellerOffer id (or template offer ref).
buyerId	ObjectId → User	yes	—	—	yes (compound)	Buyer paying.
sellerId	Mixed (ObjectId or String)	yes	—	—	yes (compound)	Seller receiving (or template seller).
amount.amount	Number	yes	—	—	—	Numeric amount.
amount.currency	String	yes	USDT	—	—	Settlement currency.
provider	String	no	shkeeper	enum: shkeeper / other	yes (compound, partial)	Payment processor.
direction	String	no	in	enum: in / out / refund	yes (compound, partial)	Flow direction.
blockchain.network	String	no	—	—	—	Network identifier.
blockchain.transactionHash	String	no	—	—	yes (sparse)	On-chain tx hash.
blockchain.blockchain	String	no	—	enum: ethereum / polygon / bsc / avalanche / solana / optimism / arbitrum / base / gnosis	—	Chain.
blockchain.token	String	no	—	—	—	Token symbol.
blockchain.sender	String	no	—	—	—	Source address.
blockchain.receiver	String	no	—	—	—	Destination address.
blockchain.confirmedAt	Date	no	—	—	—	When tx confirmed.
blockchain.confirmations	Number	no	0	—	—	Confirmation count.
status	String	no	pending	enum: pending / processing / confirmed / completed / failed / cancelled / refunded	yes (compound)	Lifecycle status.
escrowState	String	no	—	enum: funded / releasable / released / refunded / releasing / failed	—	Escrow lifecycle.
providerPaymentId	String	no	—	—	yes (sparse)	External provider id for idempotency.
metadata.userAgent	String	no	—	—	—	Browser UA.
metadata.ipAddress	String	no	—	—	—	Client IP.
metadata.walletType	String	no	—	—	—	Wallet category.
metadata.paymentMethod	String	no	—	—	—	Payment method label.
metadata.shkeeperUrl	String	no	—	—	—	Invoice URL.
metadata.shkeeperInvoiceId	String	no	—	—	—	Invoice id.
metadata.shkeeperData	Mixed	no	—	—	—	Raw provider payload.
metadata.shkeeperStatus	String	no	—	—	—	Provider status string.
metadata.balanceFiat	String	no	—	—	—	Fiat-equivalent balance.
metadata.balanceCrypto	String	no	—	—	—	Crypto balance.
metadata.cryptoName	String	no	—	—	—	Crypto label.
metadata.walletAddress	String	no	—	—	—	Wallet address.
metadata.shkeeperTaskId	String	no	—	—	—	Payout task id.
metadata.lastWebhookAt	Date	no	—	—	—	Last webhook timestamp.
metadata.webhookPayload	Mixed	no	—	—	—	Last webhook body.
metadata.createdVia	String	no	—	—	—	Origin marker.
metadata.payoutType	String	no	—	—	—	Payout sub-type.
metadata.error	String	no	—	—	—	Last error message.
metadata.failedAt	Date	no	—	—	—	When it failed.
createdAt	Date	auto	Date.now	—	yes (compound)	Mongoose timestamp.
processedAt	Date	no	—	—	—	When processing started.
completedAt	Date	no	—	—	—	When fully settled.
notes	String	no	—	—	—	Free-form notes.
updatedAt	Date	auto	—	—	—	Mongoose timestamp.

Virtuals

Virtual	Returns	Definition
paymentRef	PAY-<LAST_8_OF_ID_UPPERCASE>	backend/src/models/Payment.ts:191

The schema enables toJSON: { virtuals: true } and toObject: { virtuals: true } so the ref appears in API responses.

Indexes

Defined at backend/src/models/Payment.ts:174-188:

• { status: 1, createdAt: -1 } — admin queues.
• { buyerId: 1, status: 1 } — buyer dashboard.
• { sellerId: 1, status: 1 } — seller dashboard.
• { 'blockchain.transactionHash': 1 } (sparse) — webhook lookup by hash.
• { providerPaymentId: 1 } (sparse) — provider idempotency.
• { buyerId: 1, purchaseRequestId: 1, provider: 1, direction: 1 } (unique, partial: provider === 'shkeeper' && direction === 'in' && status === 'pending', name uniq_pending_shkeeper_by_buyer_session) — guards against duplicate pending invoices.

Pre/Post Hooks

None declared.

Instance Methods

None defined.

Static Methods

None defined.

Relationships

• References: User (buyerId, sometimes sellerId), PurchaseRequest (purchaseRequestId), SellerOffer (sellerOfferId).
• Referenced by: Indirectly through PurchaseRequest status transitions and Dispute resolution amounts; no model holds a direct foreign key back to Payment.

State Transitions

Payment status:

stateDiagram-v2
    [*] --> pending
    pending --> processing : webhook received
    processing --> confirmed : tx confirmed
    confirmed --> completed : escrow released / payout done
    pending --> cancelled : buyer aborts
    processing --> failed : provider error
    completed --> refunded : dispute resolved
    failed --> [*]
    cancelled --> [*]
    completed --> [*]
    refunded --> [*]

Escrow state (for direction: 'in'):

stateDiagram-v2
    [*] --> funded : buyer pays
    funded --> releasable : delivery confirmed
    releasable --> releasing : payout initiated
    releasing --> released : payout completed
    funded --> refunded : dispute refund
    releasing --> failed : payout error
    released --> [*]
    refunded --> [*]
    failed --> [*]

Common Queries

// Buyer history
Payment.find({ buyerId, direction: 'in' }).sort({ createdAt: -1 });

// Seller payouts
Payment.find({ sellerId, direction: 'out', status: 'completed' });

// Webhook lookup
Payment.findOne({ providerPaymentId });

// Pending escrows ready for release
Payment.find({ direction: 'in', escrowState: 'releasable' });

// Idempotent invoice creation (will fail by unique index if a pending one exists)
Payment.create({
  buyerId, purchaseRequestId, provider: 'shkeeper', direction: 'in', status: 'pending', ...
});

Related: PurchaseRequest, SellerOffer, User, Dispute.