Substrate Smart Contracts Caller

Ver. 0.4.9

About

A backend tool for executing methods on Substrate based Smart Contracts, powered by Polkadot{.js}

Installation

1. Clone the repo

2. Install all the dependencies - yarn

3. Create a .env file in the root folder with the following variables:

PHRASE=<Mnemonic_phrase_of_the_wallet_account>
WSPROVIDER=<RPC_connection_provider>
CONTRACT_ADDRESS=<deployed_smart_contract_address>
PORT=<Port_for_the_app_instance>

4. Add metadata.json file to the ./contractAPI folder, with the ABI instructions of the given smart contract

5. Run the app with yarn start command

Requirements

• Node v19.0.1
• yarn v1.22.19

Built With

• express - The server for handling and routing HTTP requests
• polkadot{.js} - Library with JS tools for Substrate based Blockchains

Application Structure

• index.ts - The entry point to the application. This file defines the express server and connects it with routes
• account/ - initiation of the account wallet used for smart contract calls
• wsProviderAPI/ - RPC provider connection
• contractAPI/ - the logic related to connecting with Smart Contract
• utils/ - all of the smaller tools reused across the app
• routes/ - routes definitions for the app
• consts/ - Constant variables that are used in the app
• controllers/ - controllers with all of the functions that can be executed in the app

Routes

Smart Contract

• GET api/contract/read - Execution of the read method on the given smart contract

EXAMPLE QUERY

http://localhost:3000/api/contract/read/?methodName=getUserActivityScore&args[]=pawel

• GET api/contract/txUrl - Previously executed transaction's block url

EXAMPLE QUERY

http://localhost:3000/api/contract/txUrl/?tx=421d940c-fe60-4706-957d-dcc62fa856be

RESPONSE BODY

{
    "transactionBlockUrl": "https://test.azero.dev/?rpc=wss%3A%2F%2Fws.test.azero.dev#/explorer/query/<block_hash>"
}

• POST api/contract/write - Execution of the write method on the given smart contract

REQUEST BODY

{
    "methodName": "name_of_the_method",
    "args": [] // array with the arguments list
}

• GET api/contract/codeHash - Previously executed transaction's block url

EXAMPLE QUERY

http://localhost:3000/api/contract/codeHash/?contract=5Egajaq39MT1Q3Y17bh5fbrQXUBgckZahq87JmfW9dJ7KYpV

RESPONSE BODY

{
    "codeHash": "<code_hash>"
}

Accounts

• GET api/account/publicKey - Account's Public Key

RESPONSE BODY

{
    "accountPublicKey": "public_key"
}

Signatures

• GET api/signature/verify - Verification of the given signature

EXAMPLE QUERY

http://localhost:3000/api/signature/verify/?message=secretmessage&signature=356765865443643643634&publicAddress=46565475474374734

RESPONSE BODY

{
    "isSignatureValid": boolean
}

License

• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)