Di/partials location formats/async writing

[MoazAlkharfan]

• Use FluidViewEngineOptions.PartialsLocationFormats to lookup partials files

  • fluid/Fluid.ViewEngine/FluidViewRenderer.cs

    Lines 284 to 307 in 5067057

    	protected virtual string ResolvePartialPath(string relativePartialPath)
    	{
    	return _partialToPartialPathCache.GetOrAdd(relativePartialPath, fileName =>
    	{
    	if (fileName.EndsWith(Constants.ViewExtension, StringComparison.OrdinalIgnoreCase))
    	{
    	return relativePartialPath;
    	}
    	foreach (var location in this._fluidViewEngineOptions.PartialsLocationFormats)
    	{
    	var partialPath = string.Format(location, fileName);
    	var layoutPathInfo = this._fluidViewEngineOptions.PartialsFileProvider.GetFileInfo(partialPath);
    	if (layoutPathInfo.Exists)
    	{
    	return partialPath;
    	}
    	}
    	return fileName;
    	});
    	}

• Use DI for FluidViewRenderer to allow for overriding

  • fluid/Fluid.MvcViewEngine/MvcViewFeaturesMvcBuilderExtensions.cs

    Lines 27 to 31 in 5067057

    	builder.Services.AddSingleton<IFluidViewRenderer>(sp =>
    	{
    	var options = sp.GetRequiredService<IOptions<FluidViewEngineOptions>>().Value;
    	return new FluidViewRenderer(options);
    	});

• Configure for FluidMvcViewOptions to have consistent options values across the inheritance hierarchy

  • fluid/Fluid.MvcViewEngine/MvcViewFeaturesMvcBuilderExtensions.cs

    Lines 19 to 26 in 7032077

    	builder.Services.AddTransient<IConfigureOptions<FluidMvcViewOptions>, FluidViewEngineOptionsSetup<FluidMvcViewOptions>>();
    	builder.Services.AddTransient<IConfigureOptions<FluidViewEngineOptions>, FluidViewEngineOptionsSetup<FluidViewEngineOptions>>();
    	if (setupAction != null)
    	{
    	builder.Services.Configure<FluidMvcViewOptions>(setupAction);
    	builder.Services.Configure(setupAction);
    	}

services
       .AddControllersWithViews()
       .AddFluid(options => {
              /// ... Anything using FluidMvcViewOptions doesn't work with the configuration set here

              /// Options need to be repeated
       });

// Need this to set mvc options
services
       .Configure<FluidMvcViewOptions>(x =>
       {
              /// Before:
              /// Options need to be repeated here

              /// After:
              // Only this is needed to be configured
              x.RenderingViewAsync = (path, viewContext, context) =>
              {
                     return ValueTask.CompletedTask;
              };
       });

• Add WriteToAsync because otherwise kestrel would throw and requires to override AllowSynchronousIO

builder.WebHost
        .UseKestrel(p =>
        {
            p.AllowSynchronousIO = true;
        });

[sebastienros]

@MoazAlkharfan I have integration the async part of your PR in #667, thanks for the contribution. I am keeping this one open since it also contains the configuration improvements but haven't looked at it closely enough to understand the problem so far (but I trust you about this).

[MoazAlkharfan]

@sebastienros Created #672