public static async Task UseExtensions(this WebAssemblyHostBuilder builder)
{
using var services = builder.Services.BuildServiceProvider();
var collection = services.GetRequiredService <ExtensionCollection>();
var httpClient = services.GetRequiredService <HttpClient>();
var jsRuntime = services.GetRequiredService <IJSRuntime>();
var logger = services.GetRequiredService <ILogger <Extension> >();
foreach (var c in collection.Extensions)
{
logger.LogInformation($"Loading {c.Metadata.Name}");
AssemblyLoadContext?assemblyLoadContext = null;
try
{
// https://github.com/dotnet/aspnetcore/issues/7917 may throw NotImplementedException
assemblyLoadContext = AssemblyLoadContext.Default;
}
catch { }
ResouceLoadContext resouceLoadContext = new ResouceLoadContext(jsRuntime,
assemblyLoadContext,
httpClient);
c.AssemblyLoadContext = resouceLoadContext.AssemblyLoadContext;
foreach (var r in c.Resources)
{
if (r.AutoLoad)
{
logger.LogInformation($"Loading resources {r.Path} from {c.Metadata.Name}");
await r.Load(resouceLoadContext);
}
}
logger.LogInformation($"Loaded {c.Metadata.Name}");
}
}
public async Task Load(ResouceLoadContext loadContext)
{
if (AutoCache)
{
if (loadContext.JSRuntime != null)
{
await JsInterop.CacheDataFromPath(loadContext.JSRuntime, Path);
}
}
switch (Type)
{
case ResourceType.Script:
if (loadContext.JSRuntime != null)
{
await JsInterop.LoadScript(loadContext.JSRuntime, Path);
}
break;
case ResourceType.StyleSheet:
if (loadContext.JSRuntime != null)
{
await JsInterop.LoadStyleSheet(loadContext.JSRuntime, Path);
}
break;
case ResourceType.DynamicLinkLibrary:
{
if (loadContext.HttpClient != null)
{
var response = await loadContext.HttpClient.GetAsync(Path);
response.EnsureSuccessStatusCode();
if (loadContext.AssemblyLoadContext != null)
{
using var stream = await response.Content.ReadAsStreamAsync();
LoadedAssembly = loadContext.AssemblyLoadContext.LoadFromStream(stream);
}
else
{
var bytes = await response.Content.ReadAsByteArrayAsync();
LoadedAssembly = Assembly.Load(bytes);
}
}
}
break;
}
}
public static async Task <Extension?> CreateExtension(this ExtensionMetadata metadata, ResouceLoadContext resouceLoadContext)
{
switch (metadata.Type)
{
case ExtensionType.Javascript:
{
return(new JSExtension(metadata));
}
case ExtensionType.CSharp:
{
Type?extensionType = null;
foreach (var r in metadata.LoadingResources)
{
await r.Load(resouceLoadContext);
if (r.Type == ResourceType.DynamicLinkLibrary)
{
var ass = r.GetLoadedAssembly();
var type = ass.GetType(metadata.ClassName, false, false);
if (type != null)
{
if (extensionType != null)
{
throw new Exception("multiple extension class");
}
extensionType = type;
}
}
}
if (extensionType == null)
{
throw new Exception("no extension class");
}
else if (!extensionType.IsSubclassOf(typeof(Extension)))
{
throw new Exception("extension class not is subclass of Extension");
}
var extension = (Extension)Activator.CreateInstance(extensionType);
return(extension);
}
}
return(null);
}