Declare the action once. Route to REST, CLI, Cron, and AI Agents.

package main

import (
    "context"
    "fmt"
    "time"

    "github.com/nexssp/kernel/action"
    "github.com/nexssp/transport/cron"
    "github.com/nexssp/transport/tbus"
    "github.com/nexssp/transport/tcli"
    "github.com/nexssp/transport/thttp"
)

type CreateOrderReq struct {
    CustomerID string `json:"customer_id" cli:"customer,c" validate:"required"`
    SKU        string `json:"sku" cli:"sku,s" validate:"required"`
    Quantity   int    `json:"quantity" cli:"qty,q" validate:"min=1"`
}

type Order struct {
    ID     string  `json:"id"`
    Status string  `json:"status"`
    Total  float64 `json:"total"`
}

// Declare pure business logic once with production-grade contracts
var CreateOrder = action.New("orders.create", func(ctx context.Context, req CreateOrderReq) (Order, error) {
    // Pure domain logic — independent of transports and database drivers
    return orders.Create(ctx, req)
}).
    Description("Creates an order, reserves inventory, and charges the customer").
    // Multi-protocol bindings
    Route(
        thttp.POST("/v1/orders"),
        tcli.Command("order create", "Provision a new customer order"),
        tbus.Topic("orders.created"),
        cron.Every(1 * time.Hour), // Optional scheduled execution
    ).
    // Security & Tenancy Guards
    RequireAuth().
    RequireRole("operator").
    RequirePermission("orders:write").
    RequireTenant().
    // Resilience & Delivery Contracts
    Idempotent(). // Deduplicates replay requests via distributed store
    Timeout(3 * time.Second).
    Retry(3, action.ExponentialJitter(50*time.Millisecond, time.Second)).
    RateLimit(100, 20).
    Transactional(db).
    Audited(auditLogger, "billing", func(req CreateOrderReq, res Order) string {
        return fmt.Sprintf("order_id=%s sku=%s customer=%s", res.ID, req.SKU, req.CustomerID)
    }).
    Build()