MerchantSlate SDK - onchain crypto payment database

MerchantSlate SDK is a TypeScript library for on-chain crypto payment databases, supporting front-end and back-end solutions across popular EVM chains. It enables product management, payment processing, and utility functions like fetching live token rates and data (e.g., relative to USDT). Install via npm, yarn, or CDN, and customize with RPCs.

Change Log

Change Log

Contract Deployed

Contract is currently deployed across popular EVM chains More Info

Example Implementation

This package is implemented at merchantslate.com Example Website Repo

Setup

Install using yarn add merchantslate or npm install merchantslate

OR use in browsers through CDN

<script 
  src="https://cdn.jsdelivr.net/npm/[email protected]/dist/browser/merchant.min.js"
></script>

Note merchant is the browser global object for this library functions.

Config

Accepts a MerchantConfigParams object (RPC urls, private key/seed, suffixes, contract address)

Note: Public RPCs obtained from https://chainlist.org/ are used as default for development only and should be updated using config

config({
  /** wallet private key (optional) 
   * used if no wallet can be connected in the setup environment 
   */
  walletPrivateKey?: string,
  /**
   * wallet seed phrase (optional) 
   * used if no wallet can be connected in the setup environment
   * cannot be used if private key is defined
   */
  walletSeedPhrase?: string,
  /** BSC RPC URL (same for any other chain)
   * all chains list available as SUPPORTED_CHAINS 
   */
  BSC_RPC: string,
  /** billion number suffix */
  billionSuffix?: string,
  /** million number suffix */
  millionSuffix?: string,
  /** MerchantSlate Contract Address (does not require change) */
  merchantSlateContract?: string,
  /** Chain RPC (pass as ${ChainId}_RPC) string for a single RPC or string[] for multiple RPCs */
  BSC_RPC?: string | string[],
});

Get Chains Data

Returns data of supported chains (BlockchainNetwork type)

getChainsData(): BlockchainNetwork[]

Get Config

Returns the current configuration object

getConfig(): MerchantConfigParams

Selected Chain

The currently selected chain ID

selectedChain: ChainIds

Set Selected Chain

Sets the selected chain

setSelectedChain(chain: ChainIds): void

Zero Address

The zero address constant

ZERO_ADDRESS: EVMAddress

Contract Errors

Object of possible error codes / messages from smart contract

contractErrors: Record<string, string>

Token

Get Token Data

Gets on-chain token metadata (symbol, name, decimals etc.)

getTokenData(
  tokenAddress: EVMAddress,
  chain: ChainIds
): Promise<TokenData>

Token Onchain Data

Maybe similar but includes additional data (e.g. balances?)

tokenOnchainData(
  tokenAddress: EVMAddress,
  chain: ChainIds
): Promise<OnchainTokenData>

Get Token Rate

Gets current rate / price of token in some unit or relative value

getTokenRate(
  tokenAddress: EVMAddress,
  chain: ChainIds
): Promise<number>

Merchant

Merchant Fee

Fee required to register as merchant on given chain (in wei or string)

merchantFee(chain: ChainIds): Promise<string>

Merchant Fee Value Text

Same as merchantFee but formatted as human readable text

merchantFeeValueText(chain: ChainIds): Promise<string>

Merchant Signup

Initiate merchant signup transaction

merchantSignup(
  chain: ChainIds
): Promise<{ hash?: string; merchantId?: string }>

Get Merchant Id

Get merchant id of connected wallet

getMerchantId(chain: ChainIds): Promise<string>

Products

Product Fee

Fee to add product on given chain

productFee(chain: ChainIds): Promise<string>

Product Fee Text

Product fee formatted as text

productFeeText(chain: ChainIds): Promise<string>

Add Product

Add or update product details

addProduct(params: { 
  chain: ChainIds; 
  productPrice: string;
  tokenAddress?: EVMAddress;
  quantity?: string; 
  commissionAddress?: string; 
  commissionPercentage?: string; 
  productId?: string; 
}): Promise<{ 
  hash: string; 
  productId: string; 
  isNew: boolean 
}>

Update Product

Update existing product

updateProduct(params: { 
  chain: ChainIds; 
  productPrice: string;
  tokenAddress?: EVMAddress;
  quantity?: string; 
  commissionAddress?: string; 
  commissionPercentage?: string; 
  productId?: string; 
}): Promise<{ 
  hash: string; 
  productId: string; 
  isNew: boolean 
}>

Delete Product

Delete a product; returns transaction hash

deleteProduct(
  chain: ChainIds, 
  productId: string
): Promise<string>

Get Products

Fetch products with optional pagination / filter

getProducts(
  chain: ChainIds, 
  pageNo?: string, 
  pageSize?: string, 
  isMerchantOnly?: boolean
): Promise<ProductDataAll>

Get Product Details

Get all data for a single product

getProductDetails(
  chain: ChainIds, 
  productId: string
): Promise<ProductData>

Load Products

Similar to getProducts but wrapped for UI loading etc.

loadProducts(params: { 
  chain: ChainIds; 
  pageNo: string; 
  pageSize: string; 
  isMerchantOnly?: boolean 
}): Promise<{ productsData: ProductDataAll }>

Payments

Get Payments

Fetch payments with pagination and optional filters

getPayments(
  chain: ChainIds, 
  pageNo?: string, 
  pageSize?: string, 
  isMerchantOnly?: boolean, 
  buyerWallet?: EVMAddress
): Promise<{ 
  currentPage: string; 
  previousPage?: string; 
  nextPage?: string; 
  totalPages: string; 
  paymentsData: PaymentDataAll 
}>

Load Payments

Same as getPayments but wrapped for UI

loadPayments(params: { 
  chain: ChainIds; 
  pageNo: string; 
  pageSize: string; 
  isMerchantOnly: boolean; 
  buyerWallet?: EVMAddress; 
}): Promise<{ 
  currentPage: string; 
  previousPage?: string; 
  nextPage?: string; 
  totalPages: string; 
  paymentsData: PaymentDataAll 
}>

Pay Product

Initiate payment transaction

payProduct(
  chain: ChainIds, 
  product: ProductChain, 
  quantity?: string
): Promise<{ 
  hash?: string; 
  paymentId?: string 
}>

Pay Value Text

Payment value converted to human readable text

payValueText(
  chain: ChainIds, 
  product: ProductChain, 
  quantity?: string
): Promise<string>

Pay Txs

Fetch transaction details for a list of payment IDs

payTxs(
  chain: ChainIds, 
  paymentIds: string[]
): Promise<{
  chainId: string,
  token: TokenData,
  amount: string,
  txs: TxObj[]
}>

Pay Validation

Validate that payment inputs are acceptable etc.

payValidation(
  chain: ChainIds, 
  product: ProductChain, 
  quantity?: string
): Promise<boolean>

Stakes

Total Stakes

Returns total stake units/stake count on the contract

totalStakes(chain: ChainIds): Promise<number>

Stakes Count

Returns count of stakes held by wallet + offered stakes

stakesCount(
  chain: ChainIds
): Promise<{ 
  holdings: number; 
  offered: number 
}>

Offer Stake

Owners offer stakes for public purchase

offerStake(
  chain: ChainIds, 
  stakeUnits: string, 
  totalValueWei: string
): Promise<string>

Stakes Offered

Get list of stake offers; optionally only for connected wallet

stakesOffered(
  chain: ChainIds, 
  walletOnly?: boolean
): Promise<{ 
  listedStakes: StakeOffers; 
  holderOffersCount: number 
}>

Transfer Stake

Transfer stakes to someone else

transferStake(
  chain: ChainIds, 
  stakeUnits: string, 
  recipientAddress: EVMAddress
): Promise<string>

Take Stake

Take an existing stake offer by id

takeStake(chain: ChainIds, offerId: string): Promise<string>

Remove Stake Offer

Remove a previously created stake offer

removeStakeOffer(
  chain: ChainIds,
  offerId: string
): Promise<string>

Wallet Methods

Browser Wallet

Returns the connected browser wallet signer or undefined

getBrowserWallet(): Promise<Signer | undefined>

Setup Provider

Returns the ethers provider based on the configuration

getProvider(): Provider

Contract Object

Returns the contract instance connected to the current chain

getContract(): Contract

Wallet Address

Returns address of connected wallet (if any)

getWalletAddress(): Promise<string | undefined>

General Methods

Integer String

Normalize number/string into integer string (no decimals)

integerString(num: string | number): string

To Wei

Convert from units to Wei (or smallest unit)

toWei(amount: string, decimals?: number): string

From Wei

Convert from Wei to human readable units

fromWei(amount: string, decimals?: number): string

Process Numbers

Format numbers suitably (commas etc.)

processNumbers(input: number | string): string

Time AMPM

Format a timestamp into human‐readable AM/PM time

timeAMPM(timestamp: number | string): string

Full Date Text

Format into full date string (day, month, year etc.)

fullDateText(timestamp: number | string): string

Truncate Text

Shorten text with ellipsis etc.

truncateText(text: string, length: number): string

Important Types

Here are major types exported:

• BlockchainNetwork — info about chain (name, chainId, etc.)
• ChainIds — supported chain IDs type
• ChainIdsEnum — supported chain IDs enum
• EVMAddress — string type representing valid Ethereum‐style address
• ErrorResponse — structure returned when some contract interaction fails
• MerchantConfigParams — config input object (RPCs, keys, suffixes, etc.)
• PayTxsData — data returned by payTxs
• Payment, PaymentChain, PaymentData, PaymentDataAll — various payment data shapes
• ProductChain, ProductData, ProductDataAll — product data shapes
• TxObj — transaction object type