Code snippet

main.go

package main

import (
    "encoding/json"
    "net/http"
    "sync"
    "time"
    "github.com/gorilla/mux"
)
// TODO: Implement in-memory store
type Payment struct {
    ID string                  `json:"id"` // self generated
    ReferenceID string         `json:"reference_id"` // client generated
    Amount int                 `json:"amount"`
    Timestamp time.Time        `json:"timestamp"` 
    PartnerReferenceID string  `json:"partner_reference_id"`// partner generated
    Status string              `json:"status"`
}

// TODO: Implement createPaymentHandler
func createPaymentHandler(w http.ResponseWriter, r *http.Request) {...}

func main() {
    r := mux.NewRouter()
    r.HandleFunc("/payments", createPaymentHandler).Methods(http.MethodPost)

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

// TODO: Write unit tests for createPaymentHandler

// Helper function to generate a unique ID for each payment
func generateID() string {
    // Implement a unique ID generation logic
    return "some-unique-id"
}