Host your built content locally during development

You can accomplish a lot of testing in the Unity Editor during the development of Loady Dungeons, but eventually you'll need to test your application on your target platform's devices to test all of your features. With Addressables content, you’ll also need to host your remote content on a CDN to test the loading and unloading of assets.

Building to your chosen platforms and introducing a CDN every time you want to test remote assets can introduce complexities to the development of your project, such as increased time costs. As a solution to these complexities, the Addressables system provides you with the Addressables Hosting window, which acts as a content server integrated into the Unity Editor.

Through this feature, the Addressables system hosts the build output the same way that a proper CDN does: it allows you to treat your Unity Editor Play mode session or a Unity Player build as a client that can connect to it in order to retrieve AssetBundles. The clients can exist on the same machine as your project or on any other machine on your local and remote networks.

Addressables Hosting lets you improve iteration times when testing your content and provides you with a clear understanding of how your application will connect to a remote server.

To simulate remote hosting with the local hosting service, let’s restructure Loady Dungeons so that it has remote assets. The Hat assets are a good candidate for this since they are already items that you might get as downloadable content (DLC) or seasonal/event items.

To set up Loady Dungeons for remote assets, follow these instructions:

1. From the main menu, select Window > Asset Management > Addressables > Settings.

2. In the Inspector window, in the Catalog section, select Build Remote Catalog. This option will enable your build content to create a manifest file in the build output directory named catalog.json that is crucial to finding all the hosted assets. This file will be discussed further in the Advanced tutorials.

3. In the Groups window, make sure that the Levels and Hats groups have their Build & Load paths property in the Content Packing & Loading schema set to Remote.

Applying these settings ensures that when the assets build, the application knows that Levels and Hats are remote.

To set profile Remote path to Editor hosted, follow these instructions:

1. Set your target platform to match the client’s platform so that you can build bundles that are compatible with that client. If the client is an Android device, switch to Android. If the client is the Windows Editor in Play mode, switch to Windows Standalone.

2. From the Profiles window, set your active profile to Default.

3. In the Default profile, make sure that the Remote path pair’s Bundle Locations dropdown is set to Editor Hosted. This will ensure that when the Addressables content is built, the application builds remote content to the location where the Unity Editor hosts it, and the game will request from the Unity Editor as a mock CDN. Hats and Levels will be retrieved in this manner.

4. From the main menu, select Edit > Project Settings > Player > Other Settings, and under Configuration, open the Allow downloads over HTTP menu and select Allowed in development builds.

By default your game is configured to deny web requests that do not use a secure transfer protocol (HTTPS). The Hosting window does not use a secure protocol, and this will make sure that the game can load hosted content while you are developing. The version of the game in Play mode will now connect, and so will Unity Players built in Development mode.

5. From the Groups window, select Build > New Build > Default Build Script to rebuild your content.

6. Make sure that the Play Mode script is set to Use Existing Build, so that the game can search for the remote AssetBundles from the host.

Your assets are now built and placed in the location that the Hosting window can deliver, and your game is configured to request from the Hosting window.

The game is configured, but if you were to play it in this state, you would receive errors as it connects. This is because the server that Hosting window uses has to be started up in order to provide the AssetBundles.

To create a new local Editor host, follow these instructions:

1. From the main menu, select Window > Asset Management > Addressables > Hosting.

2. From the Addressables Hosting window, select Create > Local Hosting service. This will create a new HTTP hosting service.

3. Rename the Local Hosting 0 service “Local Hosting Service”.

4. Select Enable to start the Local Hosting Service.

Note: In Unity versions, 2022.1 and above, HTTP downloads are disallowed by default.

5. Open the MainMenu scene and enter Play mode. The logo sprite is now loaded.

6. Select the Start button to load the LoadingScene, then select the Play button.

7. In the Hosting window, note that there are port listing events coming in. The first Hat asset is now loaded.

You can add multiple hosts to attempt to simulate the different build environments that you would see on a CDN.

Caching AssetBundles early leads to improved performance on any initial call, such as Addressables.LoadAssetAsync, which would otherwise need to download the bundles as part of their operation.

Make sure that you are aware of any caching restrictions that might apply to your target platform. For example, while mobile platforms allow you to take advantage of Unity’s AssetBundle Cache for downloaded content, this functionality is disabled by default at the Unity engine level for certain platforms, such as PlayStation 4, Nintendo Switch, and WebGL. Consider updating your base game with the new content on those platforms rather than attempting to deliver remote content from the CDN. Otherwise, you will need to create your own custom AssetBundle caching system and determine whether your solution complies with those platforms’ terms of services.

For finer control over caching, use the Caching API to manipulate the AssetBundle cache directly.

Note: You will need to wrap any calls to the Caching API with the ENABLE_CACHING defined.

Congratulations! You've learned the basics of configuring and hosting addressable assets with the Addressables system.

Put your new skills to good use as you develop more and more sophisticated games!