Integrating a Cloud Service Joe

Overview Example from our games Support in UE4 to achieve that

Cloud Based Events Timed gameplay changing events –The limited time draws players in Used to make your game “evergreen” –Retains players longer –Adds to the fun

Gears of War Gears of War 2 –Used to make gameplay balancing changes –Primarily, to create custom Horde events Gears of War 3 –Added the ability to change standard game modes Restrict weapons or change which ones were present –Allowed for custom playlists for matchmaking

Infinity Blade Infinity Blade 2 –Used to support social challenges, ClashMobs –Custom INI files detailing the challenges Infinity Blade 3 –Added the ability to patch configuration settings –Used to run special helmet events –IAP sales –The treasure chest in the Hideout

What’s Needed Cloud Service to deliver files Game support to download files Game support to merge files into game

Cloud Service System (game) cloud storage –Upload of files with start/stop times –Listing of files with full meta data –Serving of files to game client

Game Downloader Reads list of files from the Cloud Service –Verifies signatures to detect out of date files –Catches tampered with files too Downloads any missing files –Caches files to device with per device encryption –Optimization to reduce server bandwidth costs

Game Merging Gets the list of event files For each file, determines how to merge –INI & loc files get merged into the config cache –Content files replace/add to existing

Caveats Game must design for this –Must make sure that game is data driven via INI or DataTable objects –Takes planning from the beginning Not everything can be updated –E.g. very early engine config values

Game to Service Interaction Cloud Service(s) IHttpRequest IHttpResponse

Class Overview FHttpModule IHttpRequest IHttpResponse

FHttpModule Module for generic HTTP management Performs ticking Handles lifetime management

IHttpRequest Abstract interface to a platform specific request object Contains –URL –Verb (GET, PUT, POST, DELETE) –Headers –Payload Asynchronous submission to end point

IHttpResponse Abstract interface to a platform specific response object Created upon request completion Contains any headers & payload data

TJsonReader/TJsonWriter Base template classes for parsing/creating JSON payloads Generally not used directly

OnlineJsonSerializer Macro based serialization for native types without reflection Facebook account serialization: BEGIN_ONLINE_JSON_SERIALIZER ONLINE_JSON_SERIALIZE("id", UserId); ONLINE_JSON_SERIALIZE("username", UserName); ONLINE_JSON_SERIALIZE("name", RealName); ONLINE_JSON_SERIALIZE("gender", Gender); ONLINE_JSON_SERIALIZE("locale", Locale); END_ONLINE_JSON_SERIALIZER

FJsonObjectxConverter Used to serialize JSON to/from a UObject Uses UObject reflection system Easiest to use

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