Rewrite dotnet-getdocument and GetDocumentCommandInsider to retrieve all documents in one go

- #8242 1 of 2
- save a cache file listing all retrieved documents
- remove .NET Core App 2.0 support
- remove ServiceProjectReferenceMetadata.targets, related `Project` class, and searches for a project
  - tools will run within a project and get needed information from project on command line
- roll framework forward in both tools to expand their applicability

nits:
- refactor methods in `GetDocumentCommandWorker`
- reorder option addition for consistency and to place `--help` at the top of help output
- consolidate information about method signatures at top of `GetDocumentCommandWorker`
- consolidate `try` / `catch` blocks in `GetDocumentCommandWorker`

Author: dougbu

src/Mvc/GetDocumentInsider/src/Commands/CommandBase.cs

@@ -32,7 +32,6 @@ protected virtual void Validate()
         {
         }
 
-        protected virtual int Execute()
-            => 0;
+        protected virtual int Execute() => 0;
     }
 }

src/Mvc/GetDocumentInsider/src/Commands/GetDocumentCommand.cs

@@ -5,7 +5,7 @@
 using System.IO;
 using System.Linq;
 using System.Reflection;
-#if NETCOREAPP2_0
+#if NETCOREAPP2_1
 using System.Runtime.Loader;
 #endif
 using Microsoft.DotNet.Cli.CommandLine;
@@ -14,44 +14,29 @@ namespace Microsoft.Extensions.ApiDescription.Tool.Commands
 {
     internal class GetDocumentCommand : ProjectCommandBase
     {
-        internal const string FallbackDocumentName = "v1";
-        internal const string FallbackMethod = "GenerateAsync";
-        internal const string FallbackService = "Microsoft.Extensions.ApiDescription.IDocumentProvider";
-
-        private CommandOption _documentName;
-        private CommandOption _method;
+        private CommandOption _fileListPath;
         private CommandOption _output;
-        private CommandOption _service;
 
         public override void Configure(CommandLineApplication command)
         {
             base.Configure(command);
 
-            _documentName = command.Option(
-                "--documentName <Name>",
-                Resources.FormatDocumentDescription(FallbackDocumentName));
-            _method = command.Option("--method <Name>", Resources.FormatMethodDescription(FallbackMethod));
-            _output = command.Option("--output <Path>", Resources.OutputDescription);
-            _service = command.Option("--service <QualifiedName>", Resources.FormatServiceDescription(FallbackService));
+            _fileListPath = command.Option("--file-list <Path>", Resources.FileListDescription);
+            _output = command.Option("--output <Directory>", Resources.OutputDescription);
         }
 
         protected override void Validate()
         {
             base.Validate();
 
-            if (!_output.HasValue())
-            {
-                throw new CommandException(Resources.FormatMissingOption(_output.LongName));
-            }
-
-            if (_method.HasValue() && !_service.HasValue())
+            if (!_fileListPath.HasValue())
             {
-                throw new CommandException(Resources.FormatMissingOption(_service.LongName));
+                throw new CommandException(Resources.FormatMissingOption(_fileListPath.LongName));
             }
 
-            if (_service.HasValue() && !_method.HasValue())
+            if (!_output.HasValue())
             {
-                throw new CommandException(Resources.FormatMissingOption(_method.LongName));
+                throw new CommandException(Resources.FormatMissingOption(_output.LongName));
             }
         }
 
@@ -79,7 +64,7 @@ protected override int Execute()
                 }
             }
 
-#if NETCOREAPP2_0
+#if NETCOREAPP2_1
             AssemblyLoadContext.Default.Resolving += (loadContext, assemblyName) =>
             {
                 var name = assemblyName.Name;
@@ -125,7 +110,7 @@ protected override int Execute()
                 return Assembly.LoadFile(assemblyPath);
             };
 #else
-#error target frameworks need to be updated.
+#error Target frameworks need to be updated.
 #endif
 
             // Now safe to reference the application's code.
@@ -135,12 +120,10 @@ protected override int Execute()
                 var context = new GetDocumentCommandContext
                 {
                     AssemblyPath = assemblyPath,
-                    AssemblyDirectory = Path.GetDirectoryName(assemblyPath),
                     AssemblyName = Path.GetFileNameWithoutExtension(assemblyPath),
-                    DocumentName = _documentName.Value(),
-                    Method = _method.Value(),
-                    OutputPath = _output.Value(),
-                    Service = _service.Value(),
+                    FileListPath = _fileListPath.Value(),
+                    OutputDirectory = _output.Value(),
+                    ProjectName = ProjectName.Value(),
                 };
 
                 return GetDocumentCommandWorker.Process(context);

src/Mvc/GetDocumentInsider/src/Commands/GetDocumentCommandContext.cs

@@ -8,18 +8,14 @@ namespace Microsoft.Extensions.ApiDescription.Tool.Commands
     [Serializable]
     public class GetDocumentCommandContext
     {
-        public string AssemblyDirectory { get; set; }
-
         public string AssemblyName { get; set; }
 
         public string AssemblyPath { get; set; }
 
-        public string DocumentName { get; set; }
-
-        public string Method { get; set; }
+        public string FileListPath { get; set; }
 
-        public string OutputPath { get; set; }
+        public string OutputDirectory { get; set; }
 
-        public string Service { get; set; }
+        public string ProjectName { get; set; }
     }
 }