menu-feed/go/feed.go

/*
Menu feed example used in
https://developers.google.com/maps-booking/verticals/dining/guides/tutorials/tutorial-menu-feed-protos#go.
*
*/
package main

import (
	pb "feed/app/generated/food/menu/v1/proto"
	"fmt"

	localized_text "google.golang.org/genproto/googleapis/type/localized_text"
	money "google.golang.org/genproto/googleapis/type/money"
	"google.golang.org/protobuf/encoding/protojson"
	timestamppb "google.golang.org/protobuf/types/known/timestamppb"
	proto "google.golang.org/protobuf/proto"
)

func main() {

	//create a menu component
	menu := &pb.Menu{
		MenuId:      "menu1",
		MerchantIds: []string{"dining-1"},
		DisplayName: &pb.TextField{
			Text: []*localized_text.LocalizedText{{
				Text:         "Menu",
				LanguageCode: "en-us",
			}},
		},
		Language: "en-us",
		LastMerchantUpdateTime: &timestamppb.Timestamp{
			Seconds: 1633621547,
		},
	}

	//create a menu section component
	section := &pb.MenuSection{
		MenuSectionId: "appetizers",
		DisplayName: &pb.TextField{
			Text: []*localized_text.LocalizedText{{
				Text:         "Lunch Appetizers",
				LanguageCode: "en-us",
			}},
		},
		MenuItemIds: []string{"breadsticks-sauce"},
	}

	//create a menu item component
	item := &pb.MenuItem{
		MenuItemId: "breadsticks-sauce",
		DisplayName: &pb.TextField{
			Text: []*localized_text.LocalizedText{{
				Text:         "Breadsticks & Sauce",
				LanguageCode: "en-us",
			}},
		},
		Description: &pb.TextField{
			Text: []*localized_text.LocalizedText{{
				Text:         "Breakfast basket w/ side of tomato sauce (size 6 or 12)",
				LanguageCode: "en-us",
			}},
		},
		Pricing: &pb.MenuItem_MenuItemOptionSet_{
			MenuItemOptionSet: &pb.MenuItem_MenuItemOptionSet{
				MenuItemOptionIds: []string{"breadstick-sm", "breadstick-lg"},
			},
		},
	}
	imageUris := []string{
		"http://www.example.com/photos/breadsticks.jpg",
		"http://www.example.com/photos/sauce.jpg",
	}
	for _, uri := range imageUris {
		image := &pb.Image{
			Uri: uri,
		}
		item.Images = append(item.Images, image)
	}

	//create a menu item option
	option := &pb.MenuItemOption{
		MenuItemOptionId: "breadstick-sm",
		Value: &pb.MenuItemOptionProperty{
			PropertyType: pb.MenuItemOptionProperty_SIZE,
			Value: &pb.MenuItemOptionProperty_TextVal{
				TextVal: &pb.TextField{
					Text: []*localized_text.LocalizedText{{
						Text:         "Small",
						LanguageCode: "en-us",
					}},
				},
			},
		},
		OfferSet: &pb.OfferSet{
			Offers: []*pb.Offer{{
				Price: &money.Money{
					CurrencyCode: "USD",
					Units:        8,
					Nanos:        0,
				},
			}},
		},
	}

	//create feed
	feed := &pb.FoodMenuFeed{
		Data: []*pb.MenuComponent{{
			Type: &pb.MenuComponent_Menu{
				Menu: menu,
			},
		},
			{
				Type: &pb.MenuComponent_Section{
					Section: section,
				},
			},
			{
				Type: &pb.MenuComponent_Item{
					Item: item,
				},
			},
			{
				Type: &pb.MenuComponent_Option{
					Option: option,
				},
			}},
	}

	// Example testing for menu feed size
    // Protocol buffer message must be less than 2 GiB
    // https://protobuf.dev/programming-guides/proto-limits/
    // It is recommended to not exceed 200 MB, as there is an Actions
    // Center limit of 200 MB per file after compression.
	if proto.Size(feed) > 200 * 1024 * 1024 {
		// create new file
	}

	marshalOptions := protojson.MarshalOptions{
		UseProtoNames: true,
	}
	jsonBytes, _ := marshalOptions.Marshal(feed)
	fmt.Printf("message = %s", string(jsonBytes))
}