timoth-y/kicksware-api

package events

import (
    "encoding/json"
    "fmt"

    "github.com/golang/glog"
    "github.com/streadway/amqp"
    "go.kicksware.com/api/shared/api/events"
    "go.kicksware.com/api/shared/config"

    "go.kicksware.com/api/services/rating/core/service"
    ratingJson "go.kicksware.com/api/services/rating/usecase/serializer/json"
)

type Handler struct {
    EventBus *events.Broker
    Service  service.RatingService
}

func NewHandler(service service.RatingService, config config.ConnectionConfig) *Handler {
    return &Handler{
        EventBus: events.NewEventsBroker(config, "amq.topic", ratingJson.NewSerializer()),
        Service: service,
    }
}

func (h *Handler) SubscribeHandlers() {
    forever := make(chan bool)
    if err := h.EventBus.Consume("rating.view", "rating.view", h.viewsHandler, 1); err != nil {
        glog.Fatalln(err)
    }
    if err := h.EventBus.Consume("rating.search", "rating.search", h.searchesHandler, 1); err != nil {
        glog.Fatalln(err)
    }
    if err := h.EventBus.Consume("rating.order", "rating.order", h.ordersHandler, 1); err != nil {
        glog.Fatalln(err)
    }
    fmt.Println("Event listeners active...")
    <- forever
}

func (h *Handler) viewsHandler(msg amqp.Delivery) bool {
    entity, ok := getEntity(msg.Body); if !ok {
        return false
    }
    if _, err := h.Service.IncrementViews(entity); err != nil {
        return false
    }
    fmt.Printf("view event handled for: %q\n", entity)
    return true
}

func (h *Handler) ordersHandler(msg amqp.Delivery) bool {
    entity, ok := getEntity(msg.Body); if !ok {
        return false
    }
    if _, err := h.Service.IncrementOrders(entity); err != nil {
        return false
    }
    fmt.Printf("order event handled for: %q\n", entity)
    return true
}

func (h *Handler) searchesHandler(msg amqp.Delivery) bool {
    entity, ok := getEntity(msg.Body); if !ok {
        return false
    }
    if _, err := h.Service.IncrementSearches(entity); err != nil {
        return false
    }
    fmt.Printf("search event handled for: %q\n", entity)
    return true
}

func getEntity(body []byte) (string, bool) {
    var entity string
    if err := json.Unmarshal(body, &entity); err != nil {
        glog.Errorln(err)
        return "", false
    }
    return entity, true
}