majiayu000 TypeScript Integration
Complete guide to integrating Midnight Compact contracts with TypeScript applications.
Type Mapping Quick Reference
| Compact Type | TypeScript Type | Notes |
|---|---|---|
Field |
bigint |
ZK field element |
Uint<N> |
bigint |
Any bit width maps to bigint |
Boolean |
boolean |
Direct mapping |
Bytes<N> |
Uint8Array |
Fixed-length byte array |
Opaque<'string'> |
string |
UTF-8 string data |
Opaque<'Uint8Array'> |
Uint8Array |
Binary data |
struct |
{ field: Type, ... } |
Object with typed fields |
enum |
Discriminated union | { tag: 'Variant', value: T } |
Vector<T, N> |
T[] |
Array of mapped type |
Witness Implementation Pattern
import { WitnessContext } from '@midnight-ntwrk/midnight-js-types';
// Compact declaration: witness get_secret(): Field;
const witnesses = {
get_secret: ({ privateState }: WitnessContext<PrivateState>): bigint => {
return privateState.secret;
}
};
Contract Interaction Flow
1. Compile Compact → Generated TypeScript types
2. Deploy contract → Get contract address
3. Create provider → Connect to Midnight node
4. Build witnesses → Implement private data access
5. Call circuits → Execute transactions
6. Read state → Query ledger values
Quick Examples
Calling a Circuit
import { Contract } from './contract';
const result = await contract.callTx.transfer({
to: recipientAddress,
amount: 1000n
}, witnesses);
Reading Ledger State
const balance = await contract.state.balances.get(userAddress);
// balance: bigint | undefined
Deploying a Contract
import { deployContract } from '@midnight-ntwrk/midnight-js-contracts';
const { contract, address } = await deployContract(provider, {
privateStateKey: 'my-contract',
initialPrivateState: { secret: 42n },
witnesses
});
References
For detailed documentation on each topic:
- Type Mapping - Complete Compact ↔ TypeScript type correspondence
- Witness Bridge - Implementing witnesses in TypeScript
- Contract API - Generated contract interface usage
- Deployment - Contract deployment from TypeScript
Examples
Working TypeScript examples:
- Witness Implementation - Complete witness patterns
- Deploy Contract - Contract deployment flow
- Read State - Reading ledger state