Dans le tutoriel suivant, nous allons vous montrer comment créer un flux au format JSON à l'aide de la définition Google Protocol Buffers (protobuf). Nous allons utiliser le compilateur protobuf pour générer le code source en fonction du schéma protobuf. La création d'un flux à l'aide du code source généré fournit une interface simple et empêche la création d'entités de flux avec des noms ou des types de champs incorrects.
Configuration du projet
- Créez un répertoire de projet.
- Copiez le contenu de offer.proto money.proto dayofweek.proto timeofday.proto date.proto à partir des définitions proto en tant que nouveaux fichiers dans la racine du répertoire de votre projet.
- Installer le compilateur protoc
Pour générer du code source à partir des fichiers .proto, vous aurez besoin du compilateur protoc. Téléchargez le dernier binaire précompilé depuis la page de versions GitHub de Protocol Buffers.
Extrayez le fichier zip et ajoutez le chemin du fichier bin à la variable d'environnement PATH, par exemple :
unzip protoc-22.0-linux-x86_64.zip -d /usr/local/protoc export PATH="$PATH:/usr/local/protoc/bin"
Générer le code source
Python
- Installer la bibliothèque Python protobuf
pip install protobuf
- Générez le code source du client.
Créez le répertoire de sortie proto : generated
protoc --python_out=./generated offer.proto money.proto dayofweek.proto timeofday.proto date.proto
Mettez à jour la variable d'environnement PYTHONPATH pour inclure le chemin généré, par exemple :
export PYTHONPATH="$PYTHONPATH:./generated"
Si vous utilisez Bazel, essayez la règle py_proto_library au lieu d'exécuter protoc.
Exemple d'utilisation
Pour consulter l'intégralité de l'exemple de projet, cliquez ici.
import json from google.protobuf.json_format import MessageToDict from google.protobuf.timestamp_pb2 import Timestamp # Replace these imports with your actual generated proto package paths from generated import offer_pb2 from generated import money_pb2 from generated import dayofweek_pb2 from generated import timeofday_pb2 _MAX_BYTES_DATA_FILE = 200 * 1024 * 1024 def generate_offer_feed(): # Create OfferFeed feed = offer_pb2.OfferFeed() # Build the offers offer = offer_pb2.Offer( offer_id="offer-1", entity_ids=["dining-1"], offer_source=offer_pb2.OFFER_SOURCE_AGGREGATOR, action_type=offer_pb2.ACTION_TYPE_DINING, offer_modes=[ offer_pb2.OFFER_MODE_WALK_IN, offer_pb2.OFFER_MODE_FREE_RESERVATION ], offer_category=offer_pb2.OFFER_CATEGORY_BASE_OFFER, offer_details=offer_pb2.OfferDetails( offer_display_text="₹100 off on your order", # Note: If this is a 'oneof', you set the field name directly discount_value=money_pb2.Money( currency_code="INR", units=100 ) ), offer_restrictions=offer_pb2.OfferRestrictions( combinable_with_other_offers=True, combinable_offer_categories=[ offer_pb2.OFFER_CATEGORY_ADD_ON_PAYMENT_OFFER, offer_pb2.OFFER_CATEGORY_ADD_ON_COUPON_OFFER ] ), terms=offer_pb2.Terms( restricted_to_certain_users=False, terms_and_conditions="Valid on all menu items." ), validity_periods=[ offer_pb2.ValidityPeriod( valid_period=offer_pb2.ValidityRange( valid_from_time=Timestamp(seconds=1687062000), valid_through_time=Timestamp(seconds=1956556800) ), time_of_day=[ # Monday - Thursday Window offer_pb2.TimeOfDayWindow( time_windows=offer_pb2.TimeOfDayRange( open_time=timeofday_pb2.TimeOfDay(hours=13), close_time=timeofday_pb2.TimeOfDay(hours=23) ), day_of_week=[ dayofweek_pb2.DayOfWeek.MONDAY, dayofweek_pb2.DayOfWeek.TUESDAY, dayofweek_pb2.DayOfWeek.WEDNESDAY, dayofweek_pb2.DayOfWeek.THURSDAY ] ), # Friday - Sunday Window offer_pb2.TimeOfDayWindow( time_windows=offer_pb2.TimeOfDayRange( open_time=timeofday_pb2.TimeOfDay(hours=13), close_time=timeofday_pb2.TimeOfDay(hours=23, minutes=59, seconds=59) ), day_of_week=[ dayofweek_pb2.DayOfWeek.FRIDAY, dayofweek_pb2.DayOfWeek.SATURDAY, dayofweek_pb2.DayOfWeek.SUNDAY ] ) ] ) ], offer_url="https://www.example-restaurant.com/offer/base_offer_1", image_url="https://www.example-restaurant.com/images/offer_base.jpg" ) # 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 feed.ByteSize() + offer.ByteSize() < _MAX_BYTES_DATA_FILE: feed.data.append(offer) # else write current feed to file and start a new feed # Serialize to JSON # preserving_proto_field_names=True ensures camelCase becomes snake_case if defined that way in .proto json_output = json.dumps( MessageToDict(feed, preserving_proto_field_name=True) ) print(json_output) if __name__ == "__main__": generate_offer_feed()
L'exemple de code montre comment créer un flux d'offres RESTAURATION. L'exemple montre ensuite comment sérialiser le flux au format JSON.
L'API Python permet l'initialisation différée des objets imbriqués en définissant les propriétés.Java
- Ajoutez les dépendances protobuf-java et protobuf-java-util à votre projet à l'aide de Maven ou Gradle, comme décrit ici.
- Générez le code source du client.
protoc --java_out=src/main/java offer.proto money.proto dayofweek.proto timeofday.proto date.proto
Vous pouvez utiliser le protobuf-maven-plugin pour générer le code source lors de la compilation lorsque vous utilisez Maven.
Si vous utilisez Bazel, essayez la règle java_proto_library au lieu d'exécuter protoc.
Exemple d'utilisation
Pour consulter l'intégralité de l'exemple de projet, cliquez ici.
package com.example.offers; import com.google.protobuf.util.JsonFormat; import ext.maps.booking.feeds.offers.Offer; import ext.maps.booking.feeds.offers.OfferFeed; import ext.maps.booking.feeds.offers.OfferDetails; import ext.maps.booking.feeds.offers.OfferRestrictions; import ext.maps.booking.feeds.offers.Terms; import ext.maps.booking.feeds.offers.ValidityPeriod; import ext.maps.booking.feeds.offers.ValidityRange; import ext.maps.booking.feeds.offers.OfferCategory; import ext.maps.booking.feeds.offers.OfferMode; import ext.maps.booking.feeds.offers.OfferSource; import ext.maps.booking.feeds.offers.ActionType; import ext.maps.booking.feeds.offers.TimeOfDayWindow; import ext.maps.booking.feeds.offers.TimeOfDayRange; import com.google.type.Money; import com.google.protobuf.Timestamp; import com.google.type.DayOfWeek; import com.google.type.TimeOfDay; public class OfferFeedGenerator { // 200 MB public static final int MAX_BYTES_DATA_FILE = 200 * 1024 * 1024; public static void main(String[] args) throws Exception { // Create OfferFeed OfferFeed.Builder feed = OfferFeed.newBuilder(); // Build the offers Offer offer = Offer.newBuilder() .setOfferId("offer-1") .addEntityIds("dining-1") .setOfferSource(OfferSource.OFFER_SOURCE_AGGREGATOR) .setActionType(ActionType.ACTION_TYPE_DINING) .addOfferModes(OfferMode.OFFER_MODE_WALK_IN) .addOfferModes(OfferMode.OFFER_MODE_FREE_RESERVATION) .setOfferCategory(OfferCategory.OFFER_CATEGORY_BASE_OFFER) .setOfferDetails(OfferDetails.newBuilder() .setOfferDisplayText("₹100 off on your order") .setDiscountValue(Money.newBuilder() .setCurrencyCode("INR") .setUnits(100))) .setOfferRestrictions(OfferRestrictions.newBuilder() .setCombinableWithOtherOffers(true) .addCombinableOfferCategories(OfferCategory.OFFER_CATEGORY_ADD_ON_PAYMENT_OFFER) .addCombinableOfferCategories(OfferCategory.OFFER_CATEGORY_ADD_ON_COUPON_OFFER)) .setTerms(Terms.newBuilder() .setRestrictedToCertainUsers(false) .setTermsAndConditions("Valid on all menu items.")) .addValidityPeriods(ValidityPeriod.newBuilder() .setValidPeriod(ext.maps.booking.feeds.offers.ValidityRange.newBuilder() .setValidFromTime(Timestamp.newBuilder().setSeconds(1687062000)) .setValidThroughTime(Timestamp.newBuilder().setSeconds(1956556800))) // // Monday - Thursday Window .addTimeOfDay(ext.maps.booking.feeds.offers.TimeOfDayWindow.newBuilder() .setTimeWindows(ext.maps.booking.feeds.offers.TimeOfDayRange.newBuilder() .setOpenTime(com.google.type.TimeOfDay.newBuilder().setHours(13)) .setCloseTime(com.google.type.TimeOfDay.newBuilder().setHours(23))) .addDayOfWeek(DayOfWeek.MONDAY) .addDayOfWeek(DayOfWeek.TUESDAY) .addDayOfWeek(DayOfWeek.WEDNESDAY) .addDayOfWeek(DayOfWeek.THURSDAY)) // Friday - Sunday Window .addTimeOfDay(ext.maps.booking.feeds.offers.TimeOfDayWindow.newBuilder() .setTimeWindows(ext.maps.booking.feeds.offers.TimeOfDayRange.newBuilder() .setOpenTime(com.google.type.TimeOfDay.newBuilder().setHours(13)) .setCloseTime(com.google.type.TimeOfDay.newBuilder().setHours(23).setMinutes(59).setSeconds(59))) .addDayOfWeek(DayOfWeek.FRIDAY) .addDayOfWeek(DayOfWeek.SATURDAY) .addDayOfWeek(DayOfWeek.SUNDAY)) ) .setOfferUrl("https://www.example-restaurant.com/offer/base_offer_1") .setImageUrl("https://www.example-restaurant.com/images/offer_base.jpg") .build(); // Example testing for offer 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. int offerSize = offer.getSerializedSize(); int currentFeedSize = feed.build().getSerializedSize(); if (currentFeedSize + offerSize < MAX_BYTES_DATA_FILE) { feed.addData(offer); } else { // 1. Serialize and save the current 'feed' to a file // 2. Reset 'feed' to a new empty OfferFeed // 3. Add the 'offer' to the new feed } // Serialize to JSON String jsonOutput = JsonFormat.printer() .preservingProtoFieldNames() .print(feed); System.out.println(jsonOutput); } }
L'exemple de code montre comment créer un flux d'offres RESTAURATION. L'exemple montre ensuite comment sérialiser le flux au format JSON.
Go
- Installer le plug-in protoc pour Go
go install google.golang.org/protobuf/cmd/protoc-gen-go@latest
Mettez à jour la variable d'environnement PATH pour inclure le plug-in protoc-gen-go, par exemple :
export PATH="$PATH:$(go env GOPATH)/bin"
- Initialisez l'application et générez le code source du client.
go mod init feed/app mkdir generated protoc --go_out=./generated/ offer.proto money.proto dayofweek.proto timeofday.proto date.proto
Si vous utilisez Bazel, essayez la règle go_proto_library au lieu d'exécuter protoc.
Exemple d'utilisation
Pour consulter l'intégralité de l'exemple de projet, cliquez ici.
package main import ( pb "feed/app/generated/ext/maps/booking/offers/proto" "fmt" "log" money "google.golang.org/genproto/googleapis/type/money" timestamppb "google.golang.org/protobuf/types/known/timestamppb" dayofweek "google.golang.org/genproto/googleapis/type/dayofweek" timeofday "google.golang.org/genproto/googleapis/type/timeofday" proto "google.golang.org/protobuf/proto" "google.golang.org/protobuf/encoding/protojson" ) func main() { // 200 MB feed file size limit const MaxBytesDataFile = 200 * 1024 * 1024 // Create OfferFeed with offers feed := &pb.OfferFeed{} // Build the offers offer := &pb.Offer{ OfferId: "offer-1", EntityIds: []string{"dining-1"}, OfferSource: pb.OfferSource_OFFER_SOURCE_AGGREGATOR, ActionType: pb.ActionType_ACTION_TYPE_DINING, OfferModes: []pb.OfferMode{ pb.OfferMode_OFFER_MODE_WALK_IN, pb.OfferMode_OFFER_MODE_FREE_RESERVATION, }, OfferCategory: pb.OfferCategory_OFFER_CATEGORY_BASE_OFFER, OfferDetails: &pb.OfferDetails{ OfferDisplayText: "₹100 off on your order", OfferSpecification: &pb.OfferDetails_DiscountValue{ DiscountValue: &money.Money{ CurrencyCode: "INR", Units: 100, }, }, }, OfferRestrictions: &pb.OfferRestrictions{ CombinableWithOtherOffers: true, CombinableOfferCategories: []pb.OfferCategory{ pb.OfferCategory_OFFER_CATEGORY_ADD_ON_PAYMENT_OFFER, pb.OfferCategory_OFFER_CATEGORY_ADD_ON_COUPON_OFFER, }, }, Terms: &pb.Terms{ RestrictedToCertainUsers: false, TermsAndConditions: "Valid on all menu items.", }, ValidityPeriods: []*pb.ValidityPeriod{ { ValidPeriod: &pb.ValidityRange{ ValidFromTime: ×tamppb.Timestamp{Seconds: 1687062000}, ValidThroughTime: ×tamppb.Timestamp{Seconds: 1956556800}, }, TimeOfDay: []*pb.TimeOfDayWindow{ // Monday - Thursday Window { TimeWindows: &pb.TimeOfDayRange{ OpenTime: &timeofday.TimeOfDay{Hours: 13}, CloseTime: &timeofday.TimeOfDay{Hours: 23}, }, DayOfWeek: []dayofweek.DayOfWeek{ dayofweek.DayOfWeek_MONDAY, dayofweek.DayOfWeek_TUESDAY, dayofweek.DayOfWeek_WEDNESDAY, dayofweek.DayOfWeek_THURSDAY, }, }, // Friday - Sunday Window { TimeWindows: &pb.TimeOfDayRange{ OpenTime: &timeofday.TimeOfDay{Hours: 13}, CloseTime: &timeofday.TimeOfDay{ Hours: 23, Minutes: 59, Seconds: 59, }, }, DayOfWeek: []dayofweek.DayOfWeek{ dayofweek.DayOfWeek_FRIDAY, dayofweek.DayOfWeek_SATURDAY, dayofweek.DayOfWeek_SUNDAY, }, }, }, }, }, OfferUrl: "https://www.example-restaurant.com/offer/base_offer_1", ImageUrl: "https://www.example-restaurant.com/images/offer_base.jpg", } // Example testing for 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. offerSize := proto.Size(offer) currentFeedSize := proto.Size(feed) if currentFeedSize + offerSize < MaxBytesDataFile { feed.Data = append(feed.Data, offer) } else { // 1. Serialize and save the current 'feed' to a file // 2. Reset 'feed' to a new empty OfferFeed // 3. Add the 'offer' to the new feed } // Serialize to JSON marshaler := protojson.MarshalOptions{ UseProtoNames: true, } jsonOutput, err := marshaler.Marshal(feed) if err != nil { log.Fatalf("Failed to marshal feed: %v", err) } fmt.Println(string(jsonOutput)) }
L'exemple de code montre comment créer un flux d'offres RESTAURATION. L'exemple montre ensuite comment sérialiser le flux au format JSON.
TypeScript
-
Installez le plug-in protoc TypeScript.
npm init npm i -D typescript npm i ts-proto
- Créez le répertoire de sortie et générez le code source du client.
Créez le répertoire de sortie proto : src/generated
protoc --plugin="./node_modules/.bin/protoc-gen-ts_proto" --ts_proto_opt=useOptionals=all --ts_proto_opt=snakeToCamel=false --ts_proto_opt=onlyTypes=true --ts_proto_out="./src/generated" offer.proto money.proto dayofweek.proto timeofday.proto date.proto
Si vous utilisez Bazel, essayez la règle js_proto_library comme alternative à l'exécution de protoc.
Exemple d'utilisation
Pour consulter l'intégralité de l'exemple de projet, cliquez ici.
import { Offer, OfferFeed, OfferSource, ActionType, OfferMode, OfferCategory } from "./generated/offer"; // Path to your generated types import { Money } from "./generated/money"; import { DayOfWeek } from "./generated/dayofweek"; import { TimeOfDay } from "./generated/timeofday"; import { Timestamp } from "./generated/google/protobuf/timestamp"; import { Duration } from "./generated/google/protobuf/duration"; // 200 MB Limit const MAX_BYTES_DATA_FILE = 200 * 1024 * 1024; function generateOfferFeed() { // Build the Offer object const offer: Offer = { offer_id: "offer-1", entity_ids: ["dining-1"], offer_source: OfferSource.OFFER_SOURCE_AGGREGATOR, action_type: ActionType.ACTION_TYPE_DINING, offer_modes: [ OfferMode.OFFER_MODE_WALK_IN, OfferMode.OFFER_MODE_FREE_RESERVATION, ], offer_category: OfferCategory.OFFER_CATEGORY_BASE_OFFER, offer_details: { offer_display_text: "₹100 off on your order", // Set 'oneof' field: discountValue discount_value: { currency_code: "INR", units: 100, }, }, offer_restrictions: { combinable_with_other_offers: true, combinable_offer_categories: [ OfferCategory.OFFER_CATEGORY_ADD_ON_PAYMENT_OFFER, OfferCategory.OFFER_CATEGORY_ADD_ON_COUPON_OFFER, ], }, terms: { restricted_to_certain_users: false, terms_and_conditions: "Valid on all menu items.", }, validity_periods: [ { valid_period: { valid_from_time: new Date(1687062000000), valid_through_time: new Date(1956556800000), }, time_of_day: [ // Monday - Thursday Window { time_windows: { open_time: { hours: 13, minutes: 0, seconds: 0, nanos: 0 }, close_time: { hours: 23, minutes: 0, seconds: 0, nanos: 0 }, }, day_of_week: [ DayOfWeek.MONDAY, DayOfWeek.TUESDAY, DayOfWeek.WEDNESDAY, DayOfWeek.THURSDAY, ], }, // Friday - Sunday Window { time_windows: { open_time: { hours: 13, minutes: 0, seconds: 0, nanos: 0 }, close_time: { hours: 23, minutes: 59, seconds: 59, nanos: 0 }, }, day_of_week: [ DayOfWeek.FRIDAY, DayOfWeek.SATURDAY, DayOfWeek.SUNDAY, ], }, ], }, ], offer_url: "https://www.example-restaurant.com/offer/base_offer_1", image_url: "https://www.example-restaurant.com/images/offer_base.jpg", }; // 2. Initialize the Feed const feed: OfferFeed = { data: [] }; // 3. Size checking // encode().finish() returns a Uint8Array (the binary representation) const offerSize = new Blob([JSON.stringify(offer)]).size; const currentFeedSize = new Blob([JSON.stringify(feed)]).size; if (currentFeedSize + offerSize < MAX_BYTES_DATA_FILE) { if (feed.data == undefined) { feed.data = [offer]; } else { feed.data.push(offer); } } else { // Logic for file rotation goes here console.log("Feed size limit reached. Rotate file."); } // 4. Serialize to JSON // In JS/TS, we often just use JSON.stringify for the plain object // if you used proto3 and want to ensure proper enum/timestamp formatting, // use the library's toJSON method. const jsonOutput = JSON.stringify(feed); console.log(jsonOutput); } generateOfferFeed();
L'exemple de code montre comment créer un flux d'offres RESTAURATION. L'exemple montre ensuite comment sérialiser le flux au format JSON.
Remarque : Il existe des extensions de compilateur protoc tierces permettant de générer un schéma JSON à partir du schéma proto. Si vous préférez utiliser des fichiers de schéma JSON, vous pouvez consulter un exemple ici.