问题描述
在Azure Function代码中，有默认的ILogger对象来记录函数的日志，如果函数引用了一些静态对象，是否有办法使用这个默认的ILogger对象来记录日志呢？
using System.Net; using Microsoft.Azure.Functions.Worker; using Microsoft.Azure.Functions.Worker.Http; using Microsoft.Extensions.Logging; namespace Company.Function { public class HttpTrigger1 { private readonly ILogger _logger; public HttpTrigger1(ILoggerFactory loggerFactory) { _logger = loggerFactory.CreateLogger<HttpTrigger1>(); } [Function("HttpTrigger1")] public HttpResponseData Run([HttpTrigger(AuthorizationLevel.Function, "get", "post")] HttpRequestData req) { _logger.LogInformation("C# HTTP trigger function processed a request."); var response = req.CreateResponse(HttpStatusCode.OK); response.Headers.Add("Content-Type", "text/plain; charset=utf-8"); response.WriteString("Welcome to Azure Functions!"); return response; } } }
问题解答
可以的，有两种方式来实现：方式一是把_logger对象作为参数传递给静态方法，方式二是自定义一个静态ILogger 对象，然后在静态方法中使用。
方式一：把_logger对象作为参数传递
示例代码： [Function("Function1")] public HttpResponseData Run([HttpTrigger(AuthorizationLevel.Anonymous, "get", "post")] HttpRequestData req) { ... //Call Static Fun without _logger GetLocalStaticFun(); //Call static Fun with _logger GetLocalStaticFun(_logger); ... } public static void GetLocalStaticFun(ILogger _sublogger = null) { //TODO Logic process if (_sublogger != null) { _sublogger.LogInformation("this is static fucntion for testing...LogInformation. @2023/10/25"); } }
测试效果：
方式二：定义静态ILogger对象
示例代码：
static ILoggerFactory _staticLoggerFactory = LoggerFactory.Create(builder => { builder .AddFilter("Microsoft", LogLevel.Warning) .AddFilter("System", LogLevel.Warning) .AddConsole(); }); static ILogger _staticloger = _staticLoggerFactory.CreateLogger<Function1>(); public static void GetStaticLogFun() { _staticloger.LogInformation("Example log message form static class"); _staticloger.LogError("Example error message form static class"); }
注：以此种方式记录的日志，当部署到Azure Function App云服务后，通过在高级工具(kudu)站点查看日志时，与正常的日志不同，在与函数名同名的Folder中，而是在Host Folder中(C:\home\LogFiles\Application\Functions\Host)。
参考资料
ILoggerFactory static create： https://learn.microsoft.com/en-us/dotnet/core/extensions/logging?tabs=command-line#non-host-console-app
