product-sdk-contracts

Product SDK Contracts

@parity/product-sdk-contracts provides ergonomic, fully-typed smart contract interactions on Asset Hub. It supports both Solidity contracts (via pallet-revive) and PolkaVM contracts.

Quick Start: With cdm.json Manifest

import { createChainClient } from "@parity/product-sdk-chain-client";
import { paseo_asset_hub } from "@parity/product-sdk-descriptors/paseo-asset-hub";
import { ContractManager } from "@parity/product-sdk-contracts";
import cdmJson from "./cdm.json";

const client = await createChainClient({
    chains: { assetHub: paseo_asset_hub },
});

const manager = ContractManager.fromClient(cdmJson, client.raw.assetHub, paseo_asset_hub, {
    signerManager, // from @parity/product-sdk-signer
});

// Get a typed contract handle
const counter = manager.getContract("@example/counter");

// Read state
const { value } = await counter.getCount.query();
console.log("Count:", value);

// Write state
await counter.increment.tx();

client.destroy();

Quick Start: Ad-Hoc Contract

import { createChainClient } from "@parity/product-sdk-chain-client";
import { paseo_asset_hub } from "@parity/product-sdk-descriptors/paseo-asset-hub";
import { createContractFromClient } from "@parity/product-sdk-contracts";

const abi = [
    { type: "function", name: "getCount", inputs: [], outputs: [{ name: "", type: "uint32" }], stateMutability: "view" },
    { type: "function", name: "increment", inputs: [], outputs: [], stateMutability: "nonpayable" },
];

const client = await createChainClient({
    chains: { assetHub: paseo_asset_hub },
});

const counter = createContractFromClient(
    client.raw.assetHub,
    paseo_asset_hub,
    "0xYourContractAddress...",
    abi,
    { signerManager }
);

const { value } = await counter.getCount.query();
await counter.increment.tx();

client.destroy();

ContractManager vs createContract

	ContractManager	createContract / createContractFromClient
When	Multiple contracts with cdm.json manifest	Single contract, known address + ABI
Type safety	Full (with codegen)	Generic
Address management	Automatic from manifest	You provide it
Use case	Production dApps	Quick prototyping, ad-hoc contracts

Contract Methods

Each method on a contract handle has two variants:

query() — Read-Only Calls

.query() runs a ReviveApi.call dry-run on the chain — no transaction, no gas cost. Targets best-block by default so reads observe the same state a freshly-submitted .tx() sees (matching .tx()'s default resolution). Override per call with { at: "finalized" } or a block hash, or change the runtime default via createContractRuntimeFromClient(client, descriptor, { at }).

const result = await counter.getCount.query();
// result.value contains the return value on success
// No transaction, no gas cost
// Defaults to best-block; pass { at: "finalized" } for canonical state.

With options:

const result = await counter.getCount.query({
    origin: "0x...",       // Override caller address
    at: "finalized",       // Pin the dry-run to finalized state
                           // (runtime default is "best"; pass "best" | "finalized" | block hash)
});

Reverts. query() does NOT throw on a contract revert — it returns { success: false, value, gasRequired }. Two failure shapes are possible:

• Dispatch-level failures from the chain (e.g. { type: "ContractReverted" }, { type: "AccountNotMapped" }, { type: "Module", ... }) — passed through on value as-is.
• Contract-level reverts (REVERT flag set on a dispatched-OK call) — surfaced as a tagged payload: { type: "ContractRevertedWithPayload", data, reason?, decoded? }. reason is the decoded Error(string) message or a mapped Panic description; decoded carries the viem-decoded { errorName, args } for ABI-defined custom errors. Discriminate on value.type to tell the two failure paths apart.

tx() — State-Changing Transactions

const result = await counter.increment.tx();
// Submits a transaction, waits for inclusion
// result.blockHash contains the block hash

With options:

const result = await counter.increment.tx({
    signer: customSigner,  // Override the default signer
    waitFor: "finalized",  // Wait for finality (default: "best-block")
    at: "finalized",       // Pin the sizing dry-run to a block (default:
                           // runtime "best"). No-op when both gasLimit
                           // and storageDepositLimit are supplied.
    onStatus: (status) => console.log(status),
});

Pre-flight revert detection. Before submitting, tx() runs a dry-run. If the chain reports the REVERT flag is set, tx() throws ContractRevertedError and the extrinsic is NOT submitted (no gas paid). The error carries methodName, the raw data, and the same reason / decoded fields as the query payload. Passing both gasLimit AND storageDepositLimit in options skips the dry-run entirely — including this revert pre-check.

SignerManager Integration

Pass a SignerManager and a product-account signer to sign contract tx() calls:

import { SignerManager } from "@parity/product-sdk-signer";

const signerManager = new SignerManager({ ss58Prefix: 0, dappName: "your-app" });

// Establish the host session.
await signerManager.connect();

// Request a product account — its signer routes through
// `host_create_transaction` (PR #96), which preserves arbitrary signed
// extensions (e.g. `AsPgas` on Paseo Next v2). Required on any chain that
// ships signed extensions PJS doesn't know about.
const productRes = await signerManager.getProductAccount("your-app.dot", 0);
if (!productRes.ok) throw productRes.error;
const productAccount = productRes.value;

const manager = ContractManager.fromClient(cdmJson, client.raw.assetHub, paseo_asset_hub, {
    signerManager,
});

// All tx() calls sign via the product account's `host_create_transaction` path.
await counter.increment.tx({ signer: productAccount.getSigner() });

See examples/tx-demo/src/main.ts and examples/contracts-demo/src/main.ts for full end-to-end references.

You can also set a default signer or origin:

const manager = ContractManager.fromClient(cdmJson, client.raw.assetHub, paseo_asset_hub, {
    defaultSigner: mySigner,
    defaultOrigin: "0x...",
});

// Update defaults later
manager.setDefaults({
    signerManager: newSignerManager,
});

Type Codegen

Generate TypeScript types for your contracts:

import { generateContractTypes } from "@parity/product-sdk-contracts";
import { writeFileSync } from "fs";

const types = generateContractTypes([
    { library: "@example/counter", abi: counterAbi },
    { library: "@example/token", abi: tokenAbi },
]);

writeFileSync(".cdm/contracts.d.ts", types);

This generates a module augmentation that makes getContract() return fully-typed handles:

// After codegen
const counter = manager.getContract("@example/counter");
// counter.getCount is typed with correct args and return type

Loading cargo-pvm-contract Artifacts (without CDM)

For contracts built with cargo pvm-contract build, the toolchain emits two files per contract:

target/<name>.release.abi.json   # Solidity-flavoured ABI
target/<name>.release.polkavm    # PolkaVM bytecode

Use the ./pvm subpath to feed those artefacts into the contracts package without going through CDM:

import {
    parsePvmContractAbi,
    loadPvmContractAbi,
    loadPvmContractArtifacts,
} from "@parity/product-sdk-contracts/pvm";
import { createContractFromClient } from "@parity/product-sdk-contracts";
import { paseo_asset_hub } from "@parity/product-sdk-descriptors/paseo-asset-hub";

// 1. In-memory (browser-safe)
import abiJson from "./counter.release.abi.json" with { type: "json" };
const abi = parsePvmContractAbi(abiJson);

// 2. From disk (Node-only)
const abi2 = await loadPvmContractAbi("./target/counter.release.abi.json");

// 3. ABI + bytecode pair (Node-only) — useful when you also want to deploy
const { abi: abi3, bytecode } = await loadPvmContractArtifacts("./target/counter.release");

// Hand the parsed ABI straight to the existing factories
const counter = createContractFromClient(client.raw.assetHub, paseo_asset_hub, "0xC472...", abi);
const { value } = await counter.get.query();
await counter.increment.tx(1n, { signer });

The filesystem helpers lazy-import node:fs/promises so the ./pvm module remains importable in browser builds — only the call site needs to be in Node.

ContractRuntime Access

For advanced use cases, create a ContractRuntime directly:

import { createContractRuntimeFromClient, createContract } from "@parity/product-sdk-contracts";
import { paseo_asset_hub } from "@parity/product-sdk-descriptors/paseo-asset-hub";

// `at` controls which block runtime-API dry-runs target. "best" is the
// default and aligns with the .tx() resolution default; "finalized"
// reads canonical lagged state; a `0x…` block hash pins to a historical
// block. Applies to .query() *and* the .tx() / .prepare() sizing call.
// Override per call via `QueryOptions.at` / `TxOptions.at` / `PrepareOptions.at`.
const runtime = createContractRuntimeFromClient(client.raw.assetHub, paseo_asset_hub, {
    at: "best",
});

const counter = createContract(runtime, "0x...", abi, { signerManager });

The typed-API factory createContractRuntime(typedApi, { at }) is also exported — useful for tests where you already hold a typed API. Prefer createContractRuntimeFromClient on every production path.

Common Mistakes

1. Using api.contracts — There is no .contracts property on chain clients. Create ContractRuntime yourself or use ContractManager.fromClient().

2. Missing signerManager for tx() — If no signer is available, tx() throws ContractSignerMissingError.

3. Wrong signer type — Contract transactions need a PolkadotSigner. Don't confuse with StatementSignerWithKey (for statement-store).

4. Adding a spurious await — ContractManager.fromClient() and createContractFromClient() are synchronous; don't await them. Only the live-resolution factories ContractManager.fromLive() / fromLiveClient() (and withLiveContractAddresses()) return Promises.

5. Assuming tx() only fails for signer/dispatch reasons — tx() also throws ContractRevertedError when the dry-run shows the contract would revert. Catch it (or its base ContractError) if you're surfacing revert reasons to users.

6. Assuming query() throws on revert — It doesn't. Reverts come back as { success: false, value: { type: "ContractRevertedWithPayload", ... } }. Always check success before reading value as the return type.

7. Using manager.getSigner() (legacy account) on chains with unknown signed extensions — signerManager.connect() exposes legacy accounts, whose signer routes through PJS. On chains like Paseo Next v2 that ship AsPgas, PJS throws PJS does not support this signed-extension: AsPgas at signing time. Use signerManager.getProductAccount(<appOrigin>, 0) and productAccount.getSigner() instead — that path goes through host_create_transaction and preserves arbitrary extensions.

8. Assuming .query() reads finalized state — Dry-runs default to best-block, matching .tx()'s submission resolution. A .query() right after a .tx() will read what the just-landed transaction wrote, even before finalization. Pass { at: "finalized" } (per-call) or set the runtime default to "finalized" if your product needs canonical lagged reads.

Reference Files

• Contracts API - Full API surface