Discussion for IHostingEnvironment updates

[JunTaoLuo]

Discussion for aspnet/Announcements#157

We made the following changes in our updates in IHostingEnvironment:

• Added ApplicationName. This replaces IApplicationEnvironment.ApplicationName but otherwise contain the same information.
• Added ContentRootPath. This replaces IApplicationEnvironment.ApplicationBasePath but otherwise contain the same information.
• Removed Configuration
• Removed MapPath

[halter73]

@DamianEdwards I think ApplicationContentBasePath like you suggested in aspnet/PlatformAbstractions#26 is better than ContentRootPath. The latter might have made sense if it were still on IApplicationEnvironment (even then...), but I really disagree now that it's on IHostingEnvironment.

In a vacuum, I'd totally expect IHostingEnvironment.ContentRootPath to bet the path for static assets. Only if I carefully looked at all the properties on IHostingEnvironment and then read the doc comments would I realize I was wrong.

Other possible alternatives:

• ApplicationContentPath
• AspNetRootPath
• ConfigurationPath

[JunTaoLuo]

I like ApplicationContentPath slightly better. Or maybe ApplicationContentRoot or ApplicationContentBase since we know that it is a path.

[davidfowl]

ApplicaitonFilesPath bhahah

[DamianEdwards]

I don't think any of the suggested names are better than what we have already.

[pranavkm]

An FYI for folks using dotnet run with an Mvc application serving Views - with this change, your applications would have to use dotnet run -- --contentRoot $PWD to allow Mvc to locate views correctly.

[cwe1ss]

From the announcement:

This means that the fields on IApplicationEnvironment, specifically ApplicationName and ApplicationBasePath, will no longer be set.

Will IApplicationEnvironment be removed? If not, under which circumstances would we still have to use it and what would we have to do if you no longer set these properties?

[JunTaoLuo]

@cwe1ss You should be using IHostingEnvironment instead as it contains the information we used to set in IApplicationEnvironment. You should be using IHostingEnvironment.ApplicationName and IHostingEnvironment.ContentRootPath.

[shaunluttin]

What differentiates ContentRootPath from WebRootPath?

[guardrex]

@shaunluttin ContentRootPath is the new name for the application base path. WebRootPath is the path to your static assets (wwwroot or whatever you decide to call it).

[EDIT] See #450 for more info (but shown using the old naming).

[shaunluttin]

@guardrex Thank you for that. It still is not clear, though, when to use the one or the other. For instance, is this appropriate?

var contentRoot = Directory.GetCurrentDirectory();
var webRoot = Path.Combine(contentRoot, "wwwroot");

[Edit] The above doesn't seem good. We point IIS at the wwwroot directory, because that is where the web.config file lives. Result:

• Directory.CurrentDirectory() is wwwroot
• ContentRoot is wwwroot
• WebRoot is wwwroot/wwwroot

It's pretty silly, eh?! So, I am not sure how to handle that. Right now a workaround is like this, but it doesn't seem good.

// if content root is `wwwroot`, then move it up one directory
contentRoot = contentRoot.Replace("wwwroot", string.Empty);

So in IIS, the content root path is the web root path? Help me understand here.

[guardrex]

@shaunluttin If you have a wwwroot folder in your project (at the ContentRootPath path, the app base path) and you specify wwwroot in the content section of project.json, the wwwroot folder will deploy to the ContentRootPath ... so it really will just end up being ContentRootPath something like F:\mysite and WebRootPath along with it F:\mysite\wwwroot. See the structure for published output here: https://github.com/dotnet/cli/issues/937 (latest is at the bottom of the issue). Therefore ...

var contentRoot = Directory.GetCurrentDirectory();
var webRoot = Path.Combine(contentRoot, "wwwroot");

... is correct.