OpenLibx402 - Go Packages

Go implementation of the X402 protocol for enabling AI agents and APIs to autonomously pay for services using HTTP 402 "Payment Required" and Solana blockchain micropayments.

Packages

This repository contains the following packages:

• openlibx402-core - Core protocol implementation with models, errors, and Solana payment processing
• openlibx402-client - HTTP client with automatic and explicit payment handling
• openlibx402-nethttp - Middleware for standard Go net/http package
• openlibx402-echo - Middleware for Echo web framework

Installation

# Core package
go get github.com/openlibx402/go/openlibx402-core

# Client package
go get github.com/openlibx402/go/openlibx402-client

# net/http middleware
go get github.com/openlibx402/go/openlibx402-nethttp

# Echo middleware
go get github.com/openlibx402/go/openlibx402-echo

Quick Start

Server (net/http)

package main

import (
    "encoding/json"
    "net/http"

    nethttp "github.com/openlibx402/go/openlibx402-nethttp"
)

func main() {
    // Initialize X402
    nethttp.InitX402(&nethttp.Config{
        PaymentAddress: "YOUR_WALLET_ADDRESS",
        TokenMint:      "USDC_MINT_ADDRESS",
        Network:        "solana-devnet",
        AutoVerify:     true,
    })

    // Protected endpoint
    http.Handle("/premium-data", nethttp.PaymentRequired(nethttp.PaymentRequiredOptions{
        Amount:      "0.10",
        Description: "Premium market data",
    })(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        json.NewEncoder(w).Encode(map[string]string{"data": "premium content"})
    })))

    http.ListenAndServe(":8080", nil)
}

Client (Auto-Payment)

package main

import (
    "context"
    "io"
    "log"

    "github.com/gagliardetto/solana-go"
    client "github.com/openlibx402/go/openlibx402-client"
)

func main() {
    // Load your wallet keypair
    walletKeypair := solana.NewWallet()

    // Create auto client
    c := client.NewAutoClient(walletKeypair.PrivateKey, "", &client.AutoClientOptions{
        MaxPaymentAmount: "10.0",
        AutoRetry:        true,
    })
    defer c.Close()

    // Automatically handles 402 and pays
    resp, err := c.Get(context.Background(), "https://api.example.com/premium-data")
    if err != nil {
        log.Fatal(err)
    }
    defer resp.Body.Close()

    data, _ := io.ReadAll(resp.Body)
    log.Println(string(data))
}

Documentation

Each package has its own README with detailed documentation:

• openlibx402-core - Core protocol types and Solana integration
• openlibx402-client - HTTP client implementation
• openlibx402-nethttp - net/http middleware
• openlibx402-echo - Echo framework middleware

License

MIT License - See LICENSE for details