The configuration file 'config.json' was not found and is not optional - azure

Question

I use Azure Functions v2
I try to create Startup file:
[assembly: FunctionsStartup(typeof(AzureAppDomainRegistration.Startup))]
namespace AzureAppDomainRegistration
{
public class Startup : FunctionsStartup
{
public override void Configure(IFunctionsHostBuilder builder)
{
var config = new ConfigurationBuilder()
.AddJsonFile("config.json")
.Build();
var connString = config["ConnectionStrings:DataContext"];
builder.Services.AddDbContext<DataContext>(options => options
.UseLazyLoadingProxies()
.UseSqlServer(connString));
builder.Services.AddTransient<IActionsRegistrationInfo, EfActionsRegistrationInfo>();
}
}
}
File "config.json" exists and has option Always to copy:
<None Update="config.json">
<CopyToPublishDirectory>Always</CopyToPublishDirectory>
<CopyToOutputDirectory>Always</CopyToOutputDirectory>
</None>
But when I start Azure Function (locally or publish to Azure) I get an error:
Microsoft.Extensions.Configuration.FileExtensions: The configuration
file 'config.json' was not found and is not optional.
what is wrong?

Answer 1

Before .AddJsonFile() method, add this line of code: .SetBasePath(Environment.CurrentDirectory). Then in your project, right click "config.json" -> select properties -> then set "copy to output directory" to "copy always".
And note that I'm using IWebJobsStartup instead of FunctionsStartup.
Here is the code works for me:
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using System;
using System.IO;
//using WebJobsStartup instead of FunctionsStartup
[assembly: WebJobsStartup(typeof(FunctionApp20.Startup))]
namespace FunctionApp20
{
public static class Function1
{
[FunctionName("Function1")]
public static void Run([BlobTrigger("samples-workitems/{name}", Connection = "AzureWebJobsStorage")]Stream myBlob, string name, ILogger log)
{
log.LogInformation($"C# Blob trigger function Processed blob\n Name:{name} \n Size: {myBlob.Length} Bytes");
}
}
//using IWebJobsStartup instead of FunctionsStartup
public class Startup : IWebJobsStartup
{
public void Configure(IWebJobsBuilder builder)
{
var config = new ConfigurationBuilder()
.SetBasePath(Environment.CurrentDirectory)
.AddJsonFile("config.json",true,true)
.Build();
}
}
}