Depdency注入和日志记录在正常使用Azure函数时突然开始失败，而没有进行代码更改。

Question

我有一个项目，通过构造函数使用依赖注入和从ASP.NET CorewithAzureFunction2.0进行MS日志记录，该函数在本地和Azure下工作，现在有两个问题：

1)通过构造函数抛出用于注入依赖项的异常，该构造函数以前一直在工作。

2)日志记录不再写入文本文件，而文本文件以前是工作的。

下面是演示上述问题1的示例代码。

1)通过构造函数引发的依赖注入异常

除了下面的示例代码之外：

2019-03-15T01:28:45.311 [Error] Executed 'Test' (Failed, Id=6bdb0e8e-2353-4ed2-83ce-2a5288fd124d)
System.InvalidOperationException : Unable to resolve service for type 'ICar' while attempting to activate 'TestFunctions'.
   at Microsoft.Extensions.DependencyInjection.ActivatorUtilities.GetService(IServiceProvider sp,Type type,Type requiredBy,Boolean isDefaultParameterRequired)
   at lambda_method(Closure ,IServiceProvider ,Object[] )
   at Microsoft.Azure.WebJobs.Host.Executors.DefaultJobActivator.CreateInstance[T](IServiceProvider serviceProvider) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\DefaultJobActivator.cs : 42
   at Microsoft.Azure.WebJobs.Host.Executors.DefaultJobActivator.CreateInstance[T](IFunctionInstanceEx functionInstance) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\DefaultJobActivator.cs : 32
   at Microsoft.Azure.WebJobs.Host.Executors.ActivatorInstanceFactory`1.<>c__DisplayClass1_1.<.ctor>b__0(IFunctionInstanceEx i) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\ActivatorInstanceFactory.cs : 20
   at Microsoft.Azure.WebJobs.Host.Executors.ActivatorInstanceFactory`1.Create(IFunctionInstanceEx functionInstance) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\ActivatorInstanceFactory.cs : 26
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionInvoker`2.CreateInstance(IFunctionInstanceEx functionInstance) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionInvoker.cs : 44
   at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.ParameterHelper.Initialize() at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs : 845
   at async Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.TryExecuteAsyncCore(IFunctionInstanceEx functionInstance,CancellationToken cancellationToken) at C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\FunctionExecutor.cs : 116

示例代码如下：

 public class TestFunctions
    {
        private readonly ICar _car;
        private readonly ILogger _log;
        private const string RouteTemplate = "";

        public TestFunctions(
            ICar car, 
            ILoggerFactory loggerFactor)
        {
            _car = car;
            _log = loggerFactor.CreateLogger<TestFunctions>();

        }

        [FunctionName(nameof(Test))]
        public IActionResult Test(
            [HttpTrigger(AuthorizationLevel.Anonymous,"Get","post", Route = RouteTemplate + nameof(Test))]
            HttpRequest httpRequest, ExecutionContext context)
        {
            _log.LogInformation($"{nameof(Test)} started processing the request.");
            return new ContentResult { StatusCode = 200, Content = $"OK" };
        }

    }

    public interface ICar
    {
        string Name { get; }
    }

    public class Car : ICar
    {
        public string Name { get => "car name"; }
    }

[assembly: WebJobsStartup(typeof(WebJobsStartup))]
    public class WebJobsStartup : IWebJobsStartup
    {
        public void Configure(IWebJobsBuilder builder)
        {
            builder.Services.AddHttpClient();
            builder.Services.AddSingleton<ICar, Car>();
            builder.Services.AddLogging();            


        }
    }

host.json

{
  "version": "2.0",
  "extensions": {
    "http": {
      "routePrefix": "api/v1"
    }
  },
  "logging": {
    "fileLoggingMode": "always",
    "logLevel": {
      "default": "Information"
    }

  }
}

2)日志记录不再写入文本文件

当通过构造函数TestFunctions进行依赖注入时，将调用Test方法。但是，Test方法中的日志记录并不是将内容写入文件。

同样，DI和日志之前都在工作。

 public TestFunctions(
            //ICar car, 
            ILoggerFactory loggerFactor)
        {}

LogInformation内的Test方法

_log.LogInformation($"{nameof(Test)} started processing the request.");

Test方法中的日志记录并不是将内容写入文件。

2019-03-15T01:34:56.360 [Information] Initializing Host. 2019-03-15T01:34:56.371 [Information] Host initialization: ConsecutiveErrors=0, StartupCount=1 2019-03-15T01:34:56.440 [Information] ApplicationInsightsLoggerOptions {   "SamplingSettings": {
    "EvaluationInterval": "00:00:15",
    "InitialSamplingPercentage": 100.0,
    "MaxSamplingPercentage": 100.0,
    "MaxTelemetryItemsPerSecond": 5.0,
    "MinSamplingPercentage": 0.1,
    "MovingAverageRatio": 0.25,
    "SamplingPercentageDecreaseTimeout": "00:02:00",
    "SamplingPercentageIncreaseTimeout": "00:15:00"   },   "SnapshotConfiguration": null } 2019-03-15T01:34:56.441 [Information] LoggerFilterOptions {   "MinLevel": "None",   "Rules": [
    {
      "ProviderName": null,
      "CategoryName": null,
      "LogLevel": null,
      "Filter": "<AddFilter>b__0"
    },
    {
      "ProviderName": null,
      "CategoryName": null,
      "LogLevel": "Information",
      "Filter": null
    },
    {
      "ProviderName": "Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.SystemLoggerProvider",
      "CategoryName": null,
      "LogLevel": "None",
      "Filter": null
    },
    {
      "ProviderName": "Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.SystemLoggerProvider",
      "CategoryName": null,
      "LogLevel": null,
      "Filter": "<AddFilter>b__0"
    },
    {
      "ProviderName": "Microsoft.Azure.WebJobs.Logging.ApplicationInsights.ApplicationInsightsLoggerProvider",
      "CategoryName": null,
      "LogLevel": "Trace",
      "Filter": null
    }   ] } 2019-03-15T01:34:56.441 [Information] LoggerFilterOptions {   "MinLevel": "None",   "Rules": [
    {
      "ProviderName": null,
      "CategoryName": null,
      "LogLevel": null,
      "Filter": "<AddFilter>b__0"
    },
    {
      "ProviderName": null,
      "CategoryName": null,
      "LogLevel": "Information",
      "Filter": null
    },
    {
      "ProviderName": "Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.SystemLoggerProvider",
      "CategoryName": null,
      "LogLevel": "None",
      "Filter": null
    },
    {
      "ProviderName": "Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics.SystemLoggerProvider",
      "CategoryName": null,
      "LogLevel": null,
      "Filter": "<AddFilter>b__0"
    },
    {
      "ProviderName": "Microsoft.Azure.WebJobs.Logging.ApplicationInsights.ApplicationInsightsLoggerProvider",
      "CategoryName": null,
      "LogLevel": "Trace",
      "Filter": null
    }   ] } 
2019-03-15T01:34:56.441 [Information] FunctionResultAggregatorOptions
{
  "BatchSize": 1000,
  "FlushTimeout": "00:00:30",
  "IsEnabled": true
}
2019-03-15T01:34:56.441 [Information] SingletonOptions
{
  "LockPeriod": "00:00:15",
  "ListenerLockPeriod": "00:00:15",
  "LockAcquisitionTimeout": "10675199.02:48:05.4775807",
  "LockAcquisitionPollingInterval": "00:00:05",
  "ListenerLockRecoveryPollingInterval": "00:01:00"
}
2019-03-15T01:34:56.448 [Information] Starting JobHost
2019-03-15T01:34:56.451 [Information] Starting Host (HostId=My-azureportal, InstanceId=id, Version=2.0.12353.0, ProcessId=5772, AppDomainId=1, InDebugMode=True, InDiagnosticMode=False, FunctionsExtensionVersion=~2)
2019-03-15T01:34:56.488 [Information] Loading functions metadata
2019-03-15T01:34:56.645 [Information] 1 functions loaded
2019-03-15T01:34:56.810 [Information] Generating 1 job function(s)
2019-03-15T01:34:56.868 [Information] Found the following functions:
TestFunctions.Test
2019-03-15T01:34:56.868 [Information] Host initialized (410ms)
2019-03-15T01:34:56.877 [Information] Host started (418ms)
2019-03-15T01:34:56.877 [Information] Job host started
2019-03-15T01:34:57.324 [Information] Executing 'Test' (Reason='This function was programmatically called via the host APIs.', Id=my id)
2019-03-15T01:34:57.370 [Information] Executed 'Test' (Succeeded, Id=my id)
2019-03-15T01:35:02.019 [Information] Host lock lease acquired by instance ID 'id'.

VS 2017

Azure函数2.x

Answer 1

若要修复本地Azure函数的运行时问题，请参见Setting Azure Functions Runtime Version for local dev with Visual Studio 2017

溶液

当前版本的Azure函数运行时2.0.12353导致了这个问题。

https://github.com/Azure/azure-functions-host/releases

其他版本如2.0.12342.0有效

在“函数应用程序设置”下，设置如下

FUNCTIONS_EXTENSION_VERSION = 2.0.12342.0