feat: GQL Container.start.ps1 ( Fixes #12 )

Author: James Brundage

Container.start.ps1

@@ -0,0 +1,70 @@
+<#
+.SYNOPSIS
+    Starts the container.
+.DESCRIPTION
+    Starts a container.
+
+    This script should be called from the Dockerfile as the ENTRYPOINT (or from within the ENTRYPOINT).
+
+    It should be deployed to the root of the container image.
+
+    ~~~Dockerfile
+    # Thank you Microsoft!  Thank you PowerShell!  Thank you Docker!
+    FROM mcr.microsoft.com/powershell
+    # Set the shell to PowerShell (thanks again, Docker!)
+    SHELL ["/bin/pwsh", "-nologo", "-command"]
+    # Run the initialization script.  This will do all remaining initialization in a single layer.
+    RUN --mount=type=bind,src=./,target=/Initialize ./Initialize/Container.init.ps1
+
+    ENTRYPOINT ["pwsh", "-nologo", "-file", "/Container.start.ps1"]
+    ~~~
+.NOTES
+    Did you know that in PowerShell you can 'use' namespaces that do not really exist?
+    This seems like a nice way to describe a relationship to a container image.
+    That is why this file is using the namespace 'mcr.microsoft.com/powershell'.
+    (this does nothing, but most likely will be used in the future)
+#>
+using namespace 'ghcr.io/powershellweb/gql'
+
+param()
+
+$env:IN_CONTAINER = $true
+$PSStyle.OutputRendering = 'Ansi'
+
+$mountedFolders = @(if (Test-Path '/proc/mounts') {
+    (Select-String "\S+\s(?<p>\S+).+rw?,.+symlinkroot=/mnt/host" "/proc/mounts").Matches.Groups |
+        Where-Object Name -eq p |
+        Get-Item -path { $_.Value }
+})
+   
+if ($mountedFolders) {
+    "Mounted $($mountedFolders.Length) folders:" | Out-Host
+    $mountedFolders | Out-Host
+}
+
+if ($args) {
+    # If there are arguments, output them (you could handle them in a more complex way).
+    "$args" | Out-Host
+    $global:ContainerStartArguments = @() + $args
+
+    #region Custom
+    
+    #endregion Custom
+} else {
+    # If there are no arguments, see if there is a Microservice.ps1
+    if (Test-Path './Microservice.ps1') {
+        # If there is a Microservice.ps1, run it.
+        . ./Microservice.ps1
+    }
+    #region Custom
+    
+    #endregion Custom
+}
+
+# If you want to do something when the container is stopped, you can register an event.
+# This can call a script that does some cleanup, or sends a message as the service is exiting.
+Register-EngineEvent -SourceIdentifier PowerShell.Exiting -Action {
+    if (Test-Path '/Container.stop.ps1') {
+        & /Container.stop.ps1 
+    }    
+} | Out-Null