(chocolateyGH-357) Initial working version of Export Command

- This will need some refactoring, but at least functional
- This was the output from the live-stream that was done here:
https://www.youtube.com/watch?v=jFozwL8qizU

Author: gep13

src/chocolatey/chocolatey.csproj

@@ -101,6 +101,7 @@
       <Link>Properties\SolutionVersion.cs</Link>
     </Compile>
     <Compile Include="AssemblyExtensions.cs" />
+    <Compile Include="infrastructure.app\commands\ChocolateyExportCommand.cs" />
     <Compile Include="infrastructure.app\commands\ChocolateyInfoCommand.cs" />
     <Compile Include="infrastructure.app\configuration\EnvironmentSettings.cs" />
     <Compile Include="infrastructure.app\domain\GenericRegistryKey.cs" />

src/chocolatey/infrastructure.app/commands/ChocolateyExportCommand.cs

@@ -0,0 +1,88 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Xml;
+using chocolatey.infrastructure.app.attributes;
+using chocolatey.infrastructure.app.configuration;
+using chocolatey.infrastructure.app.services;
+using chocolatey.infrastructure.commandline;
+using chocolatey.infrastructure.commands;
+
+// TODO: Don't output list of packages to console
+// TODO: Update top level help document with export command
+namespace chocolatey.infrastructure.app.commands
+{
+    [CommandFor("export", "exports list of currently installed packages")]
+    public class ChocolateyExportCommand : ICommand
+    {
+        private readonly INugetService _nugetService;
+
+        public ChocolateyExportCommand(INugetService nugetService)
+        {
+            _nugetService = nugetService;
+        }
+
+        public void configure_argument_parser(OptionSet optionSet, ChocolateyConfiguration configuration)
+        {
+            // TODO: Add optionset for two new arguments
+        }
+
+        public void handle_additional_argument_parsing(IList<string> unparsedArguments, ChocolateyConfiguration configuration)
+        {
+            if (unparsedArguments.Count > 0)
+            {
+                throw new ApplicationException("Please see the help menu for the export command");
+            }
+
+            configuration.ListCommand.LocalOnly = true;
+
+            // TODO: Handle parsing of --output-file-name, --include-version-numbers
+        }
+
+        public void handle_validation(ChocolateyConfiguration configuration)
+        {
+        }
+
+        public void help_message(ChocolateyConfiguration configuration)
+        {
+            // TODO: Add actual help command
+            this.Log().Info("Export Command");
+        }
+
+        public bool may_require_admin_access()
+        {
+            return false;
+        }
+
+        public void noop(ChocolateyConfiguration configuration)
+        {
+            // TODO: Implement this
+            throw new NotImplementedException();
+        }
+
+        public void run(ChocolateyConfiguration configuration)
+        {
+            var packageResults = _nugetService.list_run(configuration).ToList();
+
+            var settings = new XmlWriterSettings { Indent = true };
+
+            // TODO: Use FileSystem abstraction, rather than direct
+            using (var xw = XmlWriter.Create("c:/temp/packages.config", settings))
+            {
+                xw.WriteStartDocument();
+                xw.WriteStartElement("packages");
+
+                foreach (var packageResult in packageResults)
+                {
+                    xw.WriteStartElement("package");
+                    xw.WriteAttributeString("id", packageResult.Package.Id);
+                    // TODO: Add parameter to specify whether to include version number or not
+                    //xw.WriteAttributeString("version", package.Version.ToString());
+                    xw.WriteEndElement();
+                }
+
+                xw.WriteEndElement();
+            }
+        }
+    }
+}

src/chocolatey/infrastructure.app/configuration/ChocolateyConfiguration.cs

@@ -50,6 +50,7 @@ public ChocolateyConfiguration()
             PinCommand = new PinCommandConfiguration();
             OutdatedCommand = new OutdatedCommandConfiguration();
             Proxy = new ProxyConfiguration();
+            ExportCommand = new ExportCommandConfiguration();
 #if DEBUG
             AllowUnofficialBuild = true;
 #endif
@@ -334,6 +335,8 @@ private void append_output(StringBuilder propertyValues, string append)
         /// </remarks>
         public OutdatedCommandConfiguration OutdatedCommand { get; set; }
 
+        public ExportCommandConfiguration ExportCommand { get; set; }
+
         /// <summary>
         /// Configuration related specifically to proxies.
         /// </summary>
@@ -538,4 +541,9 @@ public sealed class ProxyConfiguration
         public string BypassList { get; set; }
         public bool BypassOnLocal { get; set; }
     }
+
+    [Serializable]
+    public sealed class ExportCommandConfiguration
+    {
+    }
 }

src/chocolatey/infrastructure.app/registration/ContainerBinding.cs

@@ -92,7 +92,8 @@ public void RegisterComponents(Container container)
                             new ChocolateyApiKeyCommand(container.GetInstance<IChocolateyConfigSettingsService>()),
                             new ChocolateyUnpackSelfCommand(container.GetInstance<IFileSystem>()),
                             new ChocolateyVersionCommand(container.GetInstance<IChocolateyPackageService>()),
-                            new ChocolateyUpdateCommand(container.GetInstance<IChocolateyPackageService>())
+                            new ChocolateyUpdateCommand(container.GetInstance<IChocolateyPackageService>()),
+                            new ChocolateyExportCommand(container.GetInstance<INugetService>())
                         };
                     return list.AsReadOnly();
                 }, Lifestyle.Singleton);