Generating random numbers on-chain is a common task for many different projects. But generating them by simply calling randomize_lt() and random() is a bad idea, as was seen in the TON Hack Challenge example.
This repository contain two contracts that will help you in generating random numbers on-chain.
main.fc— contract that accepts queries (checkcontract/scheme.tlb) and responds with random numbers.skip.fc— contract that must be deployed in Masterchain (or some other workchain, different from the one wheremain.fcis deployed). It is just a basic echo contract. It is used to skip at least 1 block and guarantee that random is unpredictable.
- Contract sources (func):
contract/ - Tests (js):
test/
contract/skip.fc contract is deployed in Masterchain (wc -1) at address:
Ef8Nb7157K5bVxNKAvIWreRcF0RcUlzcCA7lwmewWVNtqM3s
contract/main.fc contract is deployed in Basechain (wc 0) at address:
EQB_tX9bf-CwCtfan3LaRik_K2MH0J60XRZtd0p_x3d6lW96
To generate random number, simply send a query internal message to the main contract and handle response internal message.
Check contract/scheme.tlb for exact scheme.
Tests are written in JS using Mocha and Chai libraries. Interactions with contracts are done with ton-emulator.
You can run tests with this command inside the project directory:
npm test