How to download an assetbundle into the app folder for IOS/Android and get the required model from it?

Question

Around 5 models were given the name 'kitchen' and around 3 models the name 'furniture' in AssetBundle. Then I created them into the local path using the following code:

[MenuItem("Assets/Build Home Assets")]
static void BuildKitchenAssets()
{
    BuildPipeline.BuildAssetBundles("/Users/ar/Desktop/HomeBundles",BuildAssetBundleOptions.ChunkBasedCompression,BuildTarget.iOS);
}

Later, I uploaded these files into a server. The folder structure is given in the image below:

Now I am looking to download the files into the handheld device folder (IOS/Android). This is what I want to implement:

I want to dynamically add them to a list (hamburger model). There are a few doubts. I want an efficient way to do this. Should I download all the assetbundle files from the folder structure to the device path? If already downloaded, don't download the bundle again. At the same time if I have added new models to the 'kitchen' assetbundle it has to check and update the bundle.

void Update()
{
    
}

IEnumerator GetBundles()
{
    using(UnityWebRequest uwr=UnityWebRequestAssetBundle.GetAssetBundle(url,XXXXXXXX,0))
    {
        yield return uwr.SendWebRequest();

        if (uwr.error != null)
        {
            throw new Exception("WWW download error: "+uwr.error);
        }
        AssetBundle bundle = DownloadHandlerAssetBundle.GetContent(uwr);
        if(AssetName==" ")
        {
            Instantiate(bundle.mainAsset);
        }
        else
        {
            //GameObject go=bundle.LoadAsset<GameObject>(AssetName);
            GameObject go = bundle.LoadAsset(AssetName) as GameObject;
            Instantiate(go);
        }
    }
    //How to save them into 'device' folder. For App purpose so need to connect
    //to the internet at the start and download.Then no need to download again.
    // Also check if there is any change in assetbundle.
}

Answer 1

Use the new Addressables feature. It will handle downloading to the appropriate place automatically.