line-mini-dapp

name

line-mini-dapp

description

Mini Dapp / Unifi Apps SDK official reference at API-reference depth — the DApp Portal documentation, now rebranded as Unifi. Covers the Unifi Apps SDK (`@linenext/dapp-portal-sdk`, class `DappPortalSDK`), the EIP-1193 wallet provider, the payment provider and Payment Server REST API, the event provider, Web3 gas-fee delegation, the Kaia blockchain, LINE MINI App / LINE Login LIFF / Web integration, NFT drops and rewards, and the Unifi Pay PG integration. Use this skill whenever the task touches LINE's Web3 / Mini Dapp ecosystem: integrating the Unifi Apps SDK or Mini Dapp SDK, building a Unifi App / Mini Dapp / LINE MINI App with crypto, connecting a Kaia wallet (Unifi Wallet, Kaia Wallet, OKX, Bitget), sending KAIA or USDT, signing transactions, creating in-app purchases (crypto / Stripe fiat / LINE IAP), handling payment webhooks (lockUrl, unlockUrl, paymentStatusChangeCallbackUrl), finalizing payments, settlement and chargebacks, gas-fee delegation, ERC-20 token balances, or onboarding/review of a Unifi App. Trigger on mentions of: Mini Dapp, Mini Dapp SDK, Unifi, Unifi Apps, Unifi Apps SDK, DApp Portal, Dapp Portal, DappPortalSDK, @linenext/dapp-portal-sdk, docs.dappportal.io, docs.unifi.me, payment.dappportal.io, getWalletProvider, getPaymentProvider, getEventProvider, walletProvider, paymentProvider, kaia_requestAccounts, kaia_accounts, kaia_connectAndSign, kaia_sendTransaction, kaia_signTransaction, personal_sign, getErc20TokenBalance, getErc20TokenBalanceWithDepositedBalance, startPayment, openPaymentHistory, createPayment, finalize payment, pgType, CRYPTO / STRIPE / LINE_IAP, clientId, clientSecret, chainId 1001 / 8217, Kaia blockchain, Kairos testnet, KAIA, USDT, WalletType, fee delegation, signAsFeePayer, Reown, projectId, LIFF SDK, LINE MINI App, GRAC, NFT drops.

Mini Dapp / Unifi Apps SDK Reference

API-reference-level coverage of the Mini Dapp / Unifi Apps SDK and the DApp Portal (now Unifi) ecosystem, extracted from the official documentation at https://docs.dappportal.io/ (which redirects to https://docs.unifi.me/).

The product was originally Dapp Portal and was rebranded to Unifi; Mini Dapp is now Unifi Apps and the Mini Dapp SDK is the Unifi Apps SDK. The npm package name did not change — it is still @linenext/dapp-portal-sdk, the class is still DappPortalSDK, and the API hosts still use dappportal.io.

This skill splits the docs into topic-scoped reference files. Read the reference file that matches the task — do not guess SDK method names, RPC method names, endpoint paths, or JSON shapes.

When this skill applies

Any work on a Unifi App / Mini Dapp — a Web3 service running inside LINE Messenger or on the web, powered by the Kaia blockchain:

• Installing and initializing the SDK (DappPortalSDK.init), managing the singleton instance.
• Connecting wallets and signing — WalletProvider (EIP-1193): kaia_accounts, kaia_requestAccounts, kaia_connectAndSign, personal_sign, kaia_sendTransaction, kaia_signTransaction, disconnectWallet, ERC-20 balances. Wallet types: Unifi Wallet, Kaia Wallet (extension/mobile), OKX, Bitget.
• Payments — PaymentProvider: startPayment, openPaymentHistory; the Payment Server REST API (createPayment, get info, get status, finalize); payment webhooks; pgType CRYPTO / STRIPE / LINE_IAP; settlement, refunds, chargebacks, cancellation policy.
• Mission rewards — EventProvider (getEventProvider, callback); the mission verification REST API.
• Web3 — Kaia gas-fee delegation (signAsFeePayer, fee payer servers).
• LINE integration — LINE MINI App, LINE Login LIFF, Official Account, Invite Friends (ShareTargetPicker), the LIFF SDK.
• Onboarding/review of a Unifi App; NFT drops, token/NFT rewards on the Unifi platform; the Unifi Pay PG integration.

Works for raw HTTP calls (curl, fetch) to the Payment / settlement APIs and for the SDK (@linenext/dapp-portal-sdk).

Key facts (do not get these wrong)

• npm package: @linenext/dapp-portal-sdk. SDK class: DappPortalSDK. Latest version v1.6.0. CDN: https://static.kaiawallet.io/js/dapp-portal-sdk-{version}.js.
• Blockchain: Kaia. chainId "1001" = Kairos testnet (default), "8217" = Kaia mainnet. RPC methods are prefixed kaia_.
• Credentials: clientId (used to init the SDK; becomes active only when a domain is registered) and clientSecret (server-side only, required for payments, never expose).
• API hosts: Payment Server https://payment.dappportal.io; settlement/B2B API https://api.dappportal.io; wallet https://wallet.dappportal.io.
• testMode must match chainId: testMode: true ↔ chainId 1001; testMode: false ↔ chainId 8217. A mismatch causes a payment error (v1.4.6+).
• USDT balance: Unifi auto-deposits USDT, so the pure on-chain balance often reads zero — use getErc20TokenBalanceWithDepositedBalance() for USDT.
• USDT contract on Kaia: 0xd077a400968890eacc75cdc901f0356c943e4fdb.
• In LINE MINI App / LINE Login LIFF: call liff.init() before DappPortalSDK.init(); do not trigger wallet connection on entry.

Reference file map

File	Contents
references/getting-started.md	Product naming & Dapp Portal→Unifi rebrand, SDK package & versions, obtaining clientId/clientSecret, install & DappPortalSDK.init(), the DappPortalSDK class (methods, singleton rules), build architecture (LINE MINI App / LINE Login LIFF / Web), the Unifi migration guide (USDT deposit balance, v1.6.0), demo apps & the starter template.
references/wallet-provider.md	WalletProvider (EIP-1193): getWalletProvider, getWalletType + WalletType enum, request() and every KAIA RPC method (kaia_accounts, kaia_requestAccounts, kaia_connectAndSign, personal_sign, kaia_getBalance, kaia_sendTransaction, kaia_signTransaction), disconnectWallet, getErc20TokenBalance, getErc20TokenBalanceWithDepositedBalance, error codes, compatible libraries, wallet-connect UX rules, Bitget Wallet domain verification via Reown.
references/payment-provider.md	Payment flow (6 steps), the Payment Server REST API (createPayment, get info, get status, finalize) with full request/response schemas, PaymentProvider methods (startPayment, openPaymentHistory) + error codes, payment webhooks (lock/unlock/status-change), the payment status enum, payment policy (methods, currencies, minimum charges, UX), refund / cancellation / chargeback policy, settlement (fiat & crypto, claiming USDT for Stripe).
references/event-and-web3-provider.md	EventProvider (getEventProvider, eventProvider.callback) for mission completion + the mission-verification REST API; Web3 Provider; Kaia gas-fee delegation (concept, fee payer servers, frontend & backend code, balance check).
references/line-integration.md	LINE MINI App vs LINE Login LIFF; full channel setup steps for each; Official Account setup, rich menu, multi-language welcome message automation; Invite Friends (ShareTargetPicker, isMultiple); the design guide (tab name, OpenGraph, connect button, z-index, landscape, maintenance, close dialog).
references/onboarding-and-review.md	The Join Us onboarding process; launching on Unifi Apps (eligibility, benefits, evaluation criteria); about Kaia & developer resources; review guidelines (version selection, the LINE MINI App and LIFF/Web self-checklists, compliance); "How to build successful Unifi Apps"; the full FAQ (SDK, wallet, payment, LINE integration, web3).
references/unifi-platform.md	The Unifi consumer platform (Home/Apps/Market/Trade/My); applying Apps images & info; NFT minting & Drops (collections, stages, mint flow); rewards (token/NFT missions, mission monitoring); fungible token info; the GRAC (South Korea) policy; the Growth Competition.
references/changelog.md	The SDK changelog — every version v1.2.0 → v1.6.0 with API-relevant changes (added methods, behavior changes, webhook field additions) and a compact table for stability-only releases.
references/unifi-pay.md	Unifi Pay — the separate PG-facing product (redirect-based stablecoin payment): overview, onboarding, HMAC authentication, the payment API (POST /api/v1/payment, GET /api/v1/payment/{transactionId}). Plus reusable code snippets (close confirmation dialog, React & Vanilla JS).

Quick reference

SDK surface

DappPortalSDK.init({ clientId, chainId })          → Promise<DappPortalSDK>
sdk.getWalletProvider()                            → WalletProvider
sdk.getPaymentProvider()                           → PaymentProvider
DappPortalSDK.getEventProvider()                   → EventProvider
sdk.isSupportedBrowser()                           → boolean
sdk.showUnsupportedBrowserGuide()                  → Promise<void>

walletProvider.getWalletType()                     → WalletType (Web|Liff|Extension|Mobile|OKX|BITGET)
walletProvider.request({ method, params })         → Promise<unknown>   (EIP-1193 / JSON-RPC)
walletProvider.disconnectWallet()                  → Promise<void>      (async since v1.2.12)
walletProvider.getErc20TokenBalance(contract, account)                  → Promise<hex string>
walletProvider.getErc20TokenBalanceWithDepositedBalance(contract, account) → Promise<hex string>  (use for USDT)

paymentProvider.startPayment(paymentId)            → Promise<unknown>   (resolves on CONFIRMED)
paymentProvider.openPaymentHistory()               → Promise<void>

eventProvider.callback(eventId, subMissionIndex)   → void               (mission completion banner)

KAIA RPC methods (walletProvider.request)

kaia_accounts            params: null                    → string[] (empty [] if not connected)
kaia_requestAccounts     params: null                    → string[] (shows wallet-select UI)
kaia_connectAndSign      params: [message]                → [account, signature]  (recommended)
personal_sign            params: [message, account]      → signature              (EIP-191)
kaia_getBalance          params: [account, 'latest'|'earliest'] → balance hex in kei (1 KAIA = 10^18 kei)
kaia_sendTransaction     params: [{from,to,value,gas}]    → transactionHash
kaia_signTransaction     params: [tx]                     → signed (RLP) tx        (fee-delegated flows)

Payment Server REST API — base https://payment.dappportal.io

POST /api/payment-v1/payment/create     headers X-Client-Id, X-Client-Secret  → { id }
GET  /api/payment-v1/payment/info        headers X-Client-Id, X-Client-Secret; ?id=  → full payment object
GET  /api/payment-v1/payment/status      ?id=  (no auth headers)               → { status }
POST /api/payment-v1/payment/finalize    body { id }                          → 200 (empty)

Payment webhooks (POST to your URLs): lockUrl, unlockUrl, paymentStatusChangeCallbackUrl — must use port 443 and return 200 OK.

Payment status: CREATED → STARTED → REGISTERED_ON_PG → CAPTURED → CONFIRMED → FINALIZED; plus CONFIRM_FAILED, CANCELED, REFUNDED, CHARGEBACK. pgType ∈ {CRYPTO, STRIPE, LINE_IAP}. currencyCode ∈ {USD, KRW, JPY, TWD, THB, KAIA, USDT}.

Settlement / B2B API — base https://api.dappportal.io

GET /api/b2b-v1/dapp-settlements/{client_id}/signed-receivable
    HMAC auth headers: X-Auth-Client-Id, X-Auth-Timestamp, X-Auth-Salt, X-Auth-Signature

Working rules

• Initialize the SDK once and keep it as a singleton — repeated init() calls can break the wallet connection window.
• clientId works only on a registered/whitelisted domain (http://localhost:3000 is allowed for testing). An unregistered origin → "Invalid Origin" error.
• clientSecret is server-side only — required for createPayment. Never ship it in frontend code or commit it.
• Only single-item purchases are supported in createPayment.
• Set lockUrl / unlockUrl to null when the product has no quantity limit.
• For USDT smart-contract transfers (e.g. Swap), when walletType is WEB or LIFF, add depositTokenAddress + depositAmount to kaia_sendTransaction; hard-code gas to ~0x30D40 (gas estimation reverts).
• For Bitget Wallet, complete Reown domain verification and register a projectId with Unifi, or Bitget is not shown in the wallet list.
• Crypto payment prices: KAIA up to 4 decimals, USDT up to 2 decimals. Stripe USD is in cents ($1 → 100); KRW/JPY are 1:1; THB/TWD are ×100.