Upload files via REST API

[adamdriscoll]

We need to support something like this.

Invoke-RestMethod -Uri $uri -Method Post -InFile $uploadPath -UseDefaultCredentials

In ASP.NET Core, you can upload a file by accepting IFormFile.

https://docs.microsoft.com/en-us/aspnet/core/mvc/models/file-uploads?view=aspnetcore-2.2

UD is a little different because it does it's own routing. This is where we would implement the code to accept the file somehow.

https://github.com/ironmansoftware/universal-dashboard/blob/master/src/UniversalDashboard/Controllers/ComponentController.cs#L440

I think we will have to see if we can process the body as a file somehow here:

https://github.com/ironmansoftware/universal-dashboard/blob/master/src/UniversalDashboard/Controllers/ComponentController.cs#L449

We might need to add a parameter to New-UDEndpoint to specify that this endpoint accepts a file rather than a form body.

https://github.com/ironmansoftware/universal-dashboard/blob/master/src/UniversalDashboard/Cmdlets/NewEndpointCommand.cs

[adamdriscoll]

This issue now has a bounty: https://www.bountysource.com/issues/72799550-upload-files-via-rest-api