Use volumes to share sshkey and authorized keys instead of copying and add build time variables to docker-compose

docker-compose-generator/src/BuildTimeVariableVisitor.cs

@@ -0,0 +1,52 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Text.RegularExpressions;
+using YamlDotNet.RepresentationModel;
+
+namespace DockerGenerator
+{
+	// Replace built time variable ( $<variable_name>? ) in the docker generator
+	class BuildTimeVariableVisitor : YamlVisitorBase
+	{
+		class Context
+		{
+			public List<YamlScalarNode> ToRemove = new List<YamlScalarNode>();
+		}
+		Stack<Context> _Contexts = new Stack<Context>();
+		Context CurrentContext
+		{
+			get
+			{
+				return _Contexts.TryPeek(out var ctx) ? ctx : null;
+			}
+		}
+
+		protected override void VisitChildren(YamlSequenceNode sequence)
+		{
+			_Contexts.Push(new Context());
+			base.VisitChildren(sequence);
+			var ctx = _Contexts.Pop();
+			foreach (var child in ctx.ToRemove)
+			{
+				sequence.Children.Remove(child);
+			}
+		}
+		public override void Visit(YamlScalarNode scalar)
+		{
+			bool removeNode = false;
+			scalar.Value = Regex.Replace(scalar.Value, "\\$<(.*?)>\\?", (match) =>
+			{
+				var replacedBy = Environment.GetEnvironmentVariable(match.Groups[1].Value);
+				if (string.IsNullOrEmpty(replacedBy))
+				{
+					removeNode = true;
+				}
+				return replacedBy;
+			});
+			if (removeNode)
+				CurrentContext?.ToRemove.Add(scalar);
+			base.Visit(scalar);
+		}
+	}
+}