bcfetch
Version:
A Node.js library to perform multiple fetch operations based on type, including HTTP requests, blockchain data fetching, smart contract calls, and AMM LP token price calculations.
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Markdown
[](https://badge.fury.io/js/bcfetch)
[](https://opensource.org/licenses/ISC)
A powerful library to perform multiple fetch operations based on type, including HTTP requests, blockchain data fetching, and AMM LP token price calculations. Supports both Node.js and browser environments.
- π **HTTP Operations**: GET and POST requests
- π **Blockchain Integration**: Balance queries for ERC20 tokens and Bitcoin, smart contract calls
- π° **Price Data**: Binance API integration for cryptocurrency prices
- π¦ **AMM Support**: Calculate LP token prices for Uniswap and other AMM protocols
- β‘ **Concurrent Execution**: All operations run in parallel for maximum performance
- π§ **Type-based**: Easy to extend with new operation types
```bash
npm install bcfetch
```
- **Node.js**: Full functionality
- **Browser**: All features
```javascript
const { fetch } = require('bcfetch');
const operations = [
{
type: 'http-get',
params: { url: 'https://jsonplaceholder.typicode.com/users/1' }
},
{
type: 'balanceOf',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
address: '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045'
}
},
{
type: 'binance',
params: { symbol: 'BTCUSDT' }
},
{
type: 'lpPrice',
params: {
chainid: 1,
contract: '0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc',
reverse: true
}
}
];
async function main() {
try {
const results = await fetch(operations);
console.log('Results:', results);
// results is now an array of strings in the same order as operations
} catch (error) {
console.error('Error:', error.message);
}
}
main();
```
For browser usage, the library automatically uses the browser-compatible version:
```javascript
// In browser, use the browser-compatible version
const { fetch } = require('bcfetch/browser-compatible');
const operations = [
{
type: 'binance',
params: { symbol: 'BTCUSDT' }
},
{
type: 'balanceOf',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
address: '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045'
}
}
];
async function fetchData() {
try {
const results = await fetch(operations);
console.log('Results:', results);
// results is now an array of strings in the same order as operations
} catch (error) {
console.error('Error:', error.message);
}
}
fetchData();
```
Perform HTTP GET requests.
**Parameters:**
- `url` (string): The URL to fetch
**Example:**
```javascript
{
type: 'http-get',
params: { url: 'https://api.example.com/data' }
}
```
Perform HTTP POST requests.
**Parameters:**
- `url` (string): The URL to send the request to
- `body` (object): The request body (will be JSON stringified)
**Example:**
```javascript
{
type: 'http-post',
params: {
url: 'https://api.example.com/users',
body: { name: 'John Doe', email: 'john@example.com' }
}
}
```
Get ERC20 token balance or Bitcoin balance.
**Parameters:**
- `chainid` (number|string): Chain ID (1 for Ethereum, 56 for BSC, 137 for Polygon, 'BTC' for Bitcoin)
- `contract` (string): ERC20 contract address (not required for Bitcoin)
- `address` (string): Wallet address to query
**Supported Chains:**
- Ethereum Mainnet (1)
- Binance Smart Chain (56)
- Polygon (137)
- Bitcoin ('BTC')
**Example:**
```javascript
// ERC20 token balance
{
type: 'balanceOf',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
address: '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045'
}
}
// Bitcoin balance
{
type: 'balanceOf',
params: {
chainid: 'BTC',
address: 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
}
}
```
Execute smart contract calls using raw hex data.
**Parameters:**
- `chainid` (number): Chain ID (1 for Ethereum, 56 for BSC, 137 for Polygon)
- `contract` (string): Smart contract address
- `data` (string): Raw hex data for the contract call (with or without 0x prefix)
**Supported Chains:**
- Ethereum Mainnet (1)
- Binance Smart Chain (56)
- Polygon (137)
**Example:**
```javascript
// Call ERC20 token name() method
// Function selector for name() is 0x06fdde03
{
type: 'call',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
data: '0x06fdde03'
}
}
// Call ERC20 token symbol() method
// Function selector for symbol() is 0x95d89b41
{
type: 'call',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
data: '0x95d89b41'
}
}
// Call ERC20 token balanceOf(address) method
// Function selector for balanceOf(address) is 0x70a08231
// Parameter: 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045
{
type: 'call',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
data: '0x70a08231000000000000000000000000d8dA6BF26964aF9D7eEd9e03E53415D37aA96045'
}
}
```
Get cryptocurrency prices from Binance API.
**Parameters:**
- `symbol` (string): Trading pair symbol (e.g., 'BTCUSDT', 'ETHUSDT')
**Example:**
```javascript
{
type: 'binance',
params: { symbol: 'BTCUSDT' }
}
```
Calculate AMM LP token prices for Uniswap and other AMM protocols.
**Parameters:**
- `chainid` (number): Chain ID (1 for Ethereum, 56 for BSC, 137 for Polygon)
- `contract` (string): LP contract address
- `reverse` (boolean): Price calculation direction
- `false`: Calculate token0/token1 price
- `true`: Calculate token1/token0 price
**Example:**
```javascript
// Calculate USDC/WETH price (token0/token1)
{
type: 'lpPrice',
params: {
chainid: 1,
contract: '0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc',
reverse: false
}
}
// Calculate WETH/USDC price (token1/token0)
{
type: 'lpPrice',
params: {
chainid: 1,
contract: '0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc',
reverse: true
}
}
```
Execute multiple operations concurrently and return results in the same order.
**Parameters:**
- `operations` (Array): Array of operation objects
**Returns:**
- `Promise<Array<string>>`: Array of string results in the same order as input operations
**Operation Object Structure:**
```javascript
{
type: string, // Operation type (http-get, http-post, balanceOf, call, binance, lpPrice)
params: object // Operation-specific parameters
}
```
**Result Array Structure:**
```javascript
[
"result1", // First operation result
"result2", // Second operation result
// ... more results in order
]
```
The library provides detailed error messages for different failure scenarios:
- **Invalid input**: "θΎε
₯εΏ
ι‘»ζ―δΈδΈͺζδ½ζ°η»γ"
- **Missing parameters**: Specific error for each operation type
- **Network errors**: HTTP and RPC call failures
- **Unsupported operations**: "δΈζ―ζηζδ½η±»ε: [type]"
```javascript
const { fetch } = require('bcfetch');
const operations = [
// HTTP GET request
{
type: 'http-get',
params: { url: 'https://jsonplaceholder.typicode.com/users/1' }
},
// HTTP POST request
{
type: 'http-post',
params: {
url: 'https://jsonplaceholder.typicode.com/posts',
body: { title: 'New Post', body: 'Content here', userId: 1 }
}
},
// ERC20 token balance
{
type: 'balanceOf',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
address: '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045'
}
},
// Smart contract call
{
type: 'call',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
data: '0x06fdde03' // name() function selector
}
},
// Bitcoin balance
{
type: 'balanceOf',
params: {
chainid: 'BTC',
address: 'bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq'
}
},
// Cryptocurrency price
{
type: 'binance',
params: { symbol: 'ETHUSDT' }
},
// AMM LP price
{
type: 'lpPrice',
params: {
chainid: 1,
contract: '0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc',
reverse: true
}
},
];
async function main() {
console.log('Starting operations...');
try {
const results = await fetch(operations);
console.log('All operations completed successfully!');
results.forEach((value, index) => {
console.log(`Result ${index + 1}:`, value);
});
} catch (error) {
console.error('Operation failed:', error.message);
}
}
main();
```
```javascript
const { fetch } = require('bcfetch');
// Check multiple token balances and prices
const portfolioOperations = [
// Token balances
{
type: 'balanceOf',
params: {
chainid: 1,
contract: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
address: '0xYourWalletAddress'
}
},
{
type: 'balanceOf',
params: {
chainid: 1,
contract: '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2',
address: '0xYourWalletAddress'
}
},
// Current prices
{
type: 'binance',
params: { symbol: 'USDCUSDT' }
},
{
type: 'binance',
params: { symbol: 'ETHUSDT' }
},
// LP token prices
{
type: 'lpPrice',
params: {
chainid: 1,
contract: '0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc',
reverse: false
}
}
];
async function checkPortfolio() {
try {
const results = await fetch(portfolioOperations);
// Calculate portfolio value
const usdcBalance = parseFloat(results[0]);
const wethBalance = parseFloat(results[1]);
const usdcPrice = parseFloat(results[2]);
const ethPrice = parseFloat(results[3]);
const totalValue = (usdcBalance * usdcPrice) + (wethBalance * ethPrice);
console.log('Portfolio Summary:');
console.log(`USDC: ${usdcBalance.toFixed(2)} ($${(usdcBalance * usdcPrice).toFixed(2)})`);
console.log(`WETH: ${wethBalance.toFixed(4)} ($${(wethBalance * ethPrice).toFixed(2)})`);
console.log(`Total Value: $${totalValue.toFixed(2)}`);
console.log(`USDC/WETH LP Price: ${results[4]}`);
} catch (error) {
console.error('Portfolio check failed:', error.message);
}
}
checkPortfolio();
```
- [ethers](https://www.npmjs.com/package/ethers) ^6.15.0 - Ethereum library for blockchain interactions
- [gemini-code](https://www.npmjs.com/package/gemini-code) ^0.2.4 - Additional utilities
- [cheerio](https://www.npmjs.com/package/cheerio) ^1.0.0-rc.12 - Server-side jQuery implementation for HTML parsing
- **Chain ID**: 1
- **RPC**: https://ethereum.publicnode.com
- **Chain ID**: 56
- **RPC**: https://bsc-dataseed.binance.org/
- **Chain ID**: 137
- **RPC**: https://polygon-rpc.com
- **Chain ID**: 'BTC'
- **API**: https://blockstream.info/api/
Contributions are welcome! Please feel free to submit a Pull Request.
1. Fork the repository
2. Create your feature branch (`git checkout -b feature/AmazingFeature`)
3. Commit your changes (`git commit -m 'Add some AmazingFeature'`)
4. Push to the branch (`git push origin feature/AmazingFeature`)
5. Open a Pull Request
## License
This project is licensed under the ISC License - see the [LICENSE](LICENSE) file for details.
## Changelog
### v0.6.0
- **NEW**: Added `call` operation type for smart contract calls using raw hex data
- Added support for direct contract calls with 16-bit hex data strings
- Added automatic 0x prefix handling for hex data
- Enhanced error handling for hex data validation
### v0.5.0
- **BREAKING CHANGE**: `fetch()` function now returns an array of strings instead of an array of objects
- Removed `name` field requirement from operation objects
- Simplified API - results are returned in the same order as input operations
- Updated all examples and documentation to reflect the new API
### v0.4.0
- Added support for extracting text content and attributes from web pages
- Added cheerio dependency for HTML parsing
### v0.3.1
- Fixed parameter naming consistency (chainId β chainid)
### v0.3.0
- Added `lpPrice` operation type for AMM LP token price calculations
- Added support for Uniswap V2 LP contracts
- Updated keywords and description
### v0.2.0
- Added `binance` operation type for cryptocurrency prices
- Added Bitcoin balance support
- Improved error handling
### v0.1.0
- Initial release
- HTTP GET/POST operations
- ERC20 token balance queries
- Concurrent execution support
## Support
If you encounter any issues or have questions, please open an issue on the [GitHub repository](https://github.com/your-username/bcfetch).
---
Made with β€οΈ by [Gemini](https://github.com/your-username)