那些遇到过的问题

C# Blazor WASM | Firestore：使用 Google.Cloud.Firestore.FirestoreDb.CreateAsync 时接收混合内容错误

osr*_*roc 5 firebase blazor google-cloud-firestore blazor-client-side

尝试在 C# (Blazor WASM) 中创建 FirebaseDb 对象在部署到 Firebase 后会引发阻止的混合内容错误。有没有办法强制它使用HTTPS？

错误：

阻止加载混合活动内容“ http://169.254.169.254/ ” dotnet.3.2.0-preview3.20168.1.js:1:163131 ?crit: Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100.webassembly] bla .js:1:36074 未处理的异常呈现组件：类型错误：尝试获取资源时出现网络错误。blazor.webassembly.js:1:36074 WebAssembly.JSException: TypeError: 尝试获取资源时出现网络错误。blazor.webassembly.js:1:36074 在 WebAssembly.Net.Http.HttpClient.WasmHttpMessageHandler.doFetch (System.Threading.Tasks.TaskCompletionSource1[TResult] tcs, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x257c7e0 + 0x00988> in <filename unknown>:0 blazor.webassembly.js:1:36074 at WebAssembly.Net.Http.HttpClient.WasmHttpMessageHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x255e648 + 0x00184> in <filename unknown>:0 blazor.webassembly.js:1:36074 at System.Net.Http.HttpClient.FinishSendAsyncBuffered (System.Threading.Tasks.Task1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) <0x256c970 + 0x00278> in :0 blazor.webassembly.js:1:36074 at Google.Apis.Auth .OAuth2.ComputeCredential.IsRunningOnComputeEngineNoCache () <0x24f5570 + 0x0018c> in :0 blazor.webassembly.js:1:36074 at Google.Apis.Auth.OAuth2.DefaultCredentialProvider.CreateDefaultCredentialAsync () <0x2020x0f0x20x0f0x0z0x0z0f .js:1:36074 at Google.Api.Gax.Grpc.ChannelPool.CreateChannelCredentialsUncached () <0x24cf210 + 0x000d8> in :0 blazor.webassembly.js:1:36074 at Google.Api.Gax.Grpc.ChannelPool. Google.Api.Gax.Grpc.ServiceEndpoint 端点，System.Collections.Generic.IEnumerable`1[T] channelOptions) <0x246fb30 + 0x000f4> in :0 blazor.webassembly.js:1：36074 在 Google.Cloud.Firestore.V1.FirestoreClient.CreateAsync（Google.Api.Gax.Grpc.ServiceEndpoint 端点，Google.Cloud.Firestore.V1.FirestoreSettings 设置）<0x246e908 + 0x000ec> 在：0 blazor.webassembly.js： 1:36074 at Google.Cloud.Firestore.FirestoreDb.CreateAsync (System.String projectId, Google.Cloud.Firestore.V1.FirestoreClient client) <0x2449d00 + 0x001d0> in :0 blazor.webassembly.js:1:36074 at blog。 Pages.Index.OnInitializedAsync () <0x2434eb8 + 0x000c8> in :0 blazor.webassembly.js:1:36074 at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync () <0x2330b40 + 0x00104c> in :0 blazor.webassembly.js:1:36074 1:36074 在 Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask (System.Threading.Tasks.Task taskToHandle) <0x247d5b8 + 0x000c2> 中：0 blazor.webassembly.js:1：36074

编码：

    protected override async Task OnInitializedAsync()
    {
        string projectId = "my-poject-id";
        FirestoreDb db = await FirestoreDb.CreateAsync(projectId);
    }
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Swi*_*ger 5

TL;DR
Firestore 库不应在浏览器上下文中运行。它被开发用于服务器端或管理工具中。该库将允许您在 Firestore 中执行所有操作，并将凭据发送给客户将存在安全风险。

根据您的堆栈跟踪，我假设您正在使用该Google.Cloud.Firestore库。不幸的是，这个库被设计为“服务器客户端库”。在服务器端使用的客户端库。这些“服务器客户端库”的设计与“移动/网络客户端库
” 不同。 移动/网络库将使用 Firebase 的身份验证（用户名/密码、Facebook 等），并且安全模型将应用于该用户上下文。服务器库本质上使您可以访问所有内容。

现在，您遇到的问题是由于 Blazor 不支持此 SDK 引起的。首先，GOOGLE_APPLICATION_CREDENTIALSSDK 依赖的环境变量在 Blazor 应用程序中不可用。如果可用，则无法从浏览器沙箱内访问该文件。

您可以通过使用FirestoreDbBuilder并手动设置JsonCredentials和 来避免这两个问题ProjectId，如下所示：

var builder = new FirestoreDbBuilder();
builder.JsonCredentials = "{\"type\": \"service_account\", \"project_id\": \"\", \"private_key_id\": \"\", \"private_key\": \"\", \"client_email\": \"\", \"client_id\": \"\", \"auth_uri\": \"https://accounts.google.com/o/oauth2/auth\", \"token_uri\": \"https://oauth2.googleapis.com/token\", \"auth_provider_x509_cert_url\": \"https://www.googleapis.com/oauth2/v1/certs\", \"client_x509_cert_url\": \"\" }";
builder.ProjectId = "";
FirestoreDb db = builder.Build();
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这将导致下一个问题，所使用的 GRPC 库不支持 Blazor/.NET WASM，从而导致以下堆栈跟踪：

crit: Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
      Unhandled exception rendering component: Unsupported platform.
System.InvalidOperationException: Unsupported platform.
  at Grpc.Core.Internal.NativeExtension.GetNativeLibraryFilename () [0x0003f] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:231 
  at Grpc.Core.Internal.NativeExtension.LoadUnmanagedLibrary () [0x0000a] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:93 
  at Grpc.Core.Internal.NativeExtension.LoadNativeMethods () [0x0001a] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:120 
  at Grpc.Core.Internal.NativeExtension..ctor () [0x00006] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:40 
  at Grpc.Core.Internal.NativeExtension.Get () [0x00022] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:65 
  at Grpc.Core.Internal.NativeMethods.Get () [0x00000] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeMethods.cs:49 
  at Grpc.Core.GrpcEnvironment.GrpcNativeInit () [0x00016] in T:\src\github\grpc\src\csharp\Grpc.Core\GrpcEnvironment.cs:373 
  at Grpc.Core.GrpcEnvironment..ctor () [0x0001e] in T:\src\github\grpc\src\csharp\Grpc.Core\GrpcEnvironment.cs:302 
  at Grpc.Core.GrpcEnvironment.AddRef () [0x00028] in T:\src\github\grpc\src\csharp\Grpc.Core\GrpcEnvironment.cs:78 
  at Grpc.Core.Channel..ctor (System.String target, Grpc.Core.ChannelCredentials credentials, System.Collections.Generic.IEnumerable`1[T] options) [0x00041] in T:\src\github\grpc\src\csharp\Grpc.Core\Channel.cs:70 
  at Google.Api.Gax.Grpc.GrpcCore.GrpcCoreAdapter.CreateChannelImpl (System.String endpoint, Grpc.Core.ChannelCredentials credentials, Google.Api.Gax.Grpc.GrpcChannelOptions options) [0x00000] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc.GrpcCore\GrpcCoreAdapter.cs:34 
  at Google.Api.Gax.Grpc.GrpcAdapter.CreateChannel (System.String endpoint, Grpc.Core.ChannelCredentials credentials, Google.Api.Gax.Grpc.GrpcChannelOptions options) [0x00024] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc\GrpcAdapter.cs:29 
  at Google.Api.Gax.Grpc.ClientBuilderBase`1[TClient].CreateChannel (System.String endpoint, Grpc.Core.ChannelCredentials credentials) [0x00000] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc\ClientBuilderBase.cs:423 
  at Google.Api.Gax.Grpc.ClientBuilderBase`1[TClient].CreateCallInvokerAsync (System.Threading.CancellationToken cancellationToken) [0x00145] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc\ClientBuilderBase.cs:313 
  at Google.Cloud.Firestore.V1.FirestoreClientBuilder.BuildAsyncImpl (System.Threading.CancellationToken cancellationToken) [0x00033] in /_/apis/Google.Cloud.Firestore.V1/Google.Cloud.Firestore.V1/FirestoreClient.g.cs:285 
  at Google.Cloud.Firestore.FirestoreDbBuilder.BuildAsync (System.Threading.CancellationToken cancellationToken) [0x0015a] in /_/apis/Google.Cloud.Firestore/Google.Cloud.Firestore/FirestoreDbBuilder.cs:119 
  at BlazorFirestore.Pages.FetchData.OnInitializedAsync () [0x00061] in C:\Users\niels\source\repos\BlazorFirestore\Pages\FetchData.razor:12 
  at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync () <0x2ff3be8 + 0x0013a> in <filename unknown>:0
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可以通过使用Grpc.Net.Client.Web在 Blazor 内部工作的 .NET Grpc 实现来解决此问题。创建以下类（受Google 的 Source启发）：

crit: Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
      Unhandled exception rendering component: Unsupported platform.
System.InvalidOperationException: Unsupported platform.
  at Grpc.Core.Internal.NativeExtension.GetNativeLibraryFilename () [0x0003f] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:231 
  at Grpc.Core.Internal.NativeExtension.LoadUnmanagedLibrary () [0x0000a] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:93 
  at Grpc.Core.Internal.NativeExtension.LoadNativeMethods () [0x0001a] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:120 
  at Grpc.Core.Internal.NativeExtension..ctor () [0x00006] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:40 
  at Grpc.Core.Internal.NativeExtension.Get () [0x00022] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeExtension.cs:65 
  at Grpc.Core.Internal.NativeMethods.Get () [0x00000] in T:\src\github\grpc\src\csharp\Grpc.Core\Internal\NativeMethods.cs:49 
  at Grpc.Core.GrpcEnvironment.GrpcNativeInit () [0x00016] in T:\src\github\grpc\src\csharp\Grpc.Core\GrpcEnvironment.cs:373 
  at Grpc.Core.GrpcEnvironment..ctor () [0x0001e] in T:\src\github\grpc\src\csharp\Grpc.Core\GrpcEnvironment.cs:302 
  at Grpc.Core.GrpcEnvironment.AddRef () [0x00028] in T:\src\github\grpc\src\csharp\Grpc.Core\GrpcEnvironment.cs:78 
  at Grpc.Core.Channel..ctor (System.String target, Grpc.Core.ChannelCredentials credentials, System.Collections.Generic.IEnumerable`1[T] options) [0x00041] in T:\src\github\grpc\src\csharp\Grpc.Core\Channel.cs:70 
  at Google.Api.Gax.Grpc.GrpcCore.GrpcCoreAdapter.CreateChannelImpl (System.String endpoint, Grpc.Core.ChannelCredentials credentials, Google.Api.Gax.Grpc.GrpcChannelOptions options) [0x00000] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc.GrpcCore\GrpcCoreAdapter.cs:34 
  at Google.Api.Gax.Grpc.GrpcAdapter.CreateChannel (System.String endpoint, Grpc.Core.ChannelCredentials credentials, Google.Api.Gax.Grpc.GrpcChannelOptions options) [0x00024] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc\GrpcAdapter.cs:29 
  at Google.Api.Gax.Grpc.ClientBuilderBase`1[TClient].CreateChannel (System.String endpoint, Grpc.Core.ChannelCredentials credentials) [0x00000] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc\ClientBuilderBase.cs:423 
  at Google.Api.Gax.Grpc.ClientBuilderBase`1[TClient].CreateCallInvokerAsync (System.Threading.CancellationToken cancellationToken) [0x00145] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc\ClientBuilderBase.cs:313 
  at Google.Cloud.Firestore.V1.FirestoreClientBuilder.BuildAsyncImpl (System.Threading.CancellationToken cancellationToken) [0x00033] in /_/apis/Google.Cloud.Firestore.V1/Google.Cloud.Firestore.V1/FirestoreClient.g.cs:285 
  at Google.Cloud.Firestore.FirestoreDbBuilder.BuildAsync (System.Threading.CancellationToken cancellationToken) [0x0015a] in /_/apis/Google.Cloud.Firestore/Google.Cloud.Firestore/FirestoreDbBuilder.cs:119 
  at BlazorFirestore.Pages.FetchData.OnInitializedAsync () [0x00061] in C:\Users\niels\source\repos\BlazorFirestore\Pages\FetchData.razor:12 
  at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync () <0x2ff3be8 + 0x0013a> in <filename unknown>:0
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现在设置GrpcWebAdapter.Default为FirestoreDbBuilder.GrpcAdapter：

using System;
using Grpc.Core;
using Google.Api.Gax.Grpc;
using Grpc.Net.Client;
using System.Net.Http;
using Grpc.Net.Client.Web;

// you'll need these packages
// Google.Apis.Auth, Google.Cloud.Firestore, Grpc.Net.Client, Grpc.Net.Client.Web
namespace BlazorFirestore
{
    // most of the code was borrowed from https://github.com/googleapis/gax-dotnet/blob/master/Google.Api.Gax.Grpc.GrpcNetClient/GrpcNetClientAdapter.cs
    public sealed class GrpcWebAdapter : GrpcAdapter
    {
        // this HttpClient using the GrpcWebHandler and mode is crucial to get Grpc to work for Firestore
        private static HttpClient httpClient = new HttpClient(new GrpcWebHandler(GrpcWebMode.GrpcWeb, new HttpClientHandler()));

        // Note: this is "Default" rather than "Instance" as we expect to have other factory methods later, e.g. accepting
        // an HTTP client factory.

        /// <summary>
        /// Returns the default instance of this class.
        /// </summary>
        public static GrpcWebAdapter Default { get; } = new GrpcWebAdapter();

        private GrpcWebAdapter()
        {
        }

        /// <inheritdoc />
        protected override ChannelBase CreateChannelImpl(string endpoint, ChannelCredentials credentials, Google.Api.Gax.Grpc.GrpcChannelOptions options)
        {
            var grpcNetClientOptions = ConvertOptions(credentials, options);
            var address = ConvertEndpoint(endpoint);
            return GrpcChannel.ForAddress(address, grpcNetClientOptions);
        }

        // Internal for testing
        internal static global::Grpc.Net.Client.GrpcChannelOptions ConvertOptions(ChannelCredentials credentials, Google.Api.Gax.Grpc.GrpcChannelOptions options)
        {
            // If service config resolution is explicitly enabled, throw - we can't support that,
            // and users may be depending on it.
            if (options.EnableServiceConfigResolution == true)
            {
                throw new ArgumentException($"{nameof(options.EnableServiceConfigResolution)} is not currently supported in {nameof(GrpcWebAdapter)}");
            }

            if (options.CustomOptions.Count > 0)
            {
                throw new ArgumentException($"Custom options are not currently supported in {nameof(GrpcWebAdapter)}");
            }

            // Options we ignore:
            // - PrimaryUserAgent
            // - KeepAliveTime

            return new global::Grpc.Net.Client.GrpcChannelOptions
            {
                Credentials = credentials,
                MaxReceiveMessageSize = options.MaxReceiveMessageSize,
                MaxSendMessageSize = options.MaxSendMessageSize,
                // pass the GrpcWeb version of the httpclient
                HttpClient = httpClient
            };
        }

        // Internal for testing
        internal static string ConvertEndpoint(string endpoint) =>
            // Note that we assume HTTPS for any bare address; this feels like a reasonable assumption for now.
            endpoint.StartsWith("http:", StringComparison.Ordinal) || endpoint.StartsWith("https:", StringComparison.Ordinal)
            ? endpoint : $"https://{endpoint}";
    }
}
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我们又近了一步，但现在我们遇到了 CORS 安全问题，因为这种与 Firestore 通信的方式并非设计为从浏览器运行，并且无法与此 SDK 结合配置 CORS。这些是产生的错误：

Access to fetch at 'https://firestore.googleapis.com/google.firestore.v1.Firestore/Commit' from origin 'https://localhost:5001' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

dotnet.3.2.0.js:1 POST https://firestore.googleapis.com/google.firestore.v1.Firestore/Commit net::ERR_FAILED

blazor.webassembly.js:1 crit: Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
      Unhandled exception rendering component: Status(StatusCode="Internal", Detail="Error starting gRPC call. JSException: TypeError: Failed to fetch", DebugException="WebAssembly.JSException: TypeError: Failed to fetch
        at System.Net.Http.WebAssemblyHttpHandler.doFetch (System.Threading.Tasks.TaskCompletionSource`1[TResult] tcs, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x3c61b60 + 0x00a30> in <filename unknown>:0 
        at System.Net.Http.WebAssemblyHttpHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x3c24040 + 0x00174> in <filename unknown>:0 
        at Grpc.Net.Client.Web.GrpcWebHandler.SendAsyncCore (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) [0x00092] in /_/src/Grpc.Net.Client.Web/GrpcWebHandler.cs:137 
        at System.Net.Http.HttpClient.FinishSendAsyncUnbuffered (System.Threading.Tasks.Task`1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) <0x3d9ae50 + 0x00134> in <filename unknown>:0 
        at Grpc.Net.Client.Internal.GrpcCall`2[TRequest,TResponse].RunCall (System.Net.Http.HttpRequestMessage request, System.Nullable`1[T] timeout) [0x0020c] in /_/src/Grpc.Net.Client/Internal/GrpcCall.cs:477 ")
Grpc.Core.RpcException: Status(StatusCode="Internal", Detail="Error starting gRPC call. JSException: TypeError: Failed to fetch", DebugException="WebAssembly.JSException: TypeError: Failed to fetch
  at System.Net.Http.WebAssemblyHttpHandler.doFetch (System.Threading.Tasks.TaskCompletionSource`1[TResult] tcs, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x3c61b60 + 0x00a30> in <filename unknown>:0 
  at System.Net.Http.WebAssemblyHttpHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) <0x3c24040 + 0x00174> in <filename unknown>:0 
  at Grpc.Net.Client.Web.GrpcWebHandler.SendAsyncCore (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) [0x00092] in /_/src/Grpc.Net.Client.Web/GrpcWebHandler.cs:137 
  at System.Net.Http.HttpClient.FinishSendAsyncUnbuffered (System.Threading.Tasks.Task`1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) <0x3d9ae50 + 0x00134> in <filename unknown>:0 
  at Grpc.Net.Client.Internal.GrpcCall`2[TRequest,TResponse].RunCall (System.Net.Http.HttpRequestMessage request, System.Nullable`1[T] timeout) [0x0020c] in /_/src/Grpc.Net.Client/Internal/GrpcCall.cs:477 ")
  at Google.Api.Gax.Grpc.ApiCallRetryExtensions+<>c__DisplayClass0_0`2[TRequest,TResponse].<WithRetry>b__0 (TRequest request, Google.Api.Gax.Grpc.CallSettings callSettings) [0x00051] in T:\src\github\gax-dotnet\releasebuild\Google.Api.Gax.Grpc\ApiCallRetryExtensions.cs:27 
  at Google.Cloud.Firestore.WriteBatch.CommitAsync (Google.Protobuf.ByteString transactionId, System.Threading.CancellationToken cancellationToken) [0x000b5] in /_/apis/Google.Cloud.Firestore/Google.Cloud.Firestore/WriteBatch.cs:231 
  at Google.Cloud.Firestore.DocumentReference.SetAsync (System.Object documentData, Google.Cloud.Firestore.SetOptions options, System.Threading.CancellationToken cancellationToken) [0x0004b] in /_/apis/Google.Cloud.Firestore/Google.Cloud.Firestore/DocumentReference.cs:181 
  at BlazorFirestore.Pages.FetchData.OnInitializedAsync () [0x00166] in C:\Users\niels\source\repos\BlazorFirestore\Pages\FetchData.razor:21 
  at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync () <0x2ff3be8 + 0x0013a> in <filename unknown>:0 
  at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask (System.Threading.Tasks.Task taskToHandle) <0x3905a50 + 0x000b6> in <filename unknown>:0
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当您使用 明确在浏览器中禁用 CORS 时 .\chrome.exe --disable-web-security，结果将是身份验证成功，但实际的 API 将返回 404。
我不清楚为什么它返回 404。我可以Grpc.Net.Client.Web使用 Fiddler 嗅探版本，但默认实现不会被 Fiddler 拦截。看起来网络版本使用了不支持的不同协议/传输。希望有人可以解决下一个问题。

结论：.NET 的 Firestore 库不应该在浏览器沙箱中使用，并且不支持这种方式。

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