How to interact with external merchants located outside the perimeter?

If merchants are located in the external perimeter, interaction with them is usually organized through APIs or integration gateways that ensure secure data exchange between internal systems and external services. It is important to consider security issues, such as using authentication and encryption.

Example approach:

• Use REST API with OAuth 2.0 for merchant authorization.
• Configure an API Gateway for access control and monitoring.
• Ensure logging and request tracing for audit purposes.

Example of a merchant API request in Go:

package main

import (
    "bytes"
    "fmt"
    "net/http"
)

func main() {
    url := "https://merchant.example.com/api/orders"
    jsonData := []byte(`{"order_id":12345}`)

    req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonData))
    if err != nil {
        panic(err)
    }
    req.Header.Set("Content-Type", "application/json")
    req.Header.Set("Authorization", "Bearer your_access_token")

    client := &http.Client{}
    resp, err := client.Do(req)
    if err != nil {
        panic(err)
    }
    defer resp.Body.Close()

    fmt.Println("Response status:", resp.Status)
}

Thus, interaction is built through protected APIs with access control and monitoring.