C#: Some re-factoring of NugetPackages and logic for file downloading.

Author: michaelnebel

csharp/autobuilder/Semmle.Autobuild.Shared/BuildActions.cs

@@ -1,13 +1,11 @@
-using Semmle.Util;
-using System;
+using System;
 using System.Collections.Generic;
 using System.Diagnostics;
-using System.IO;
-using System.Xml;
-using System.Net.Http;
 using System.Diagnostics.CodeAnalysis;
-using System.Threading.Tasks;
+using System.IO;
 using System.Runtime.InteropServices;
+using System.Xml;
+using Semmle.Util;
 
 namespace Semmle.Autobuild.Shared
 {
@@ -283,17 +281,8 @@ XmlDocument IBuildActions.LoadXml(string filename)
 
         public string EnvironmentExpandEnvironmentVariables(string s) => Environment.ExpandEnvironmentVariables(s);
 
-        private static async Task DownloadFileAsync(string address, string filename)
-        {
-            using var httpClient = new HttpClient();
-            using var request = new HttpRequestMessage(HttpMethod.Get, address);
-            using var contentStream = await (await httpClient.SendAsync(request)).Content.ReadAsStreamAsync();
-            using var stream = new FileStream(filename, FileMode.Create, FileAccess.Write, FileShare.None, 4096, true);
-            await contentStream.CopyToAsync(stream);
-        }
-
         public void DownloadFile(string address, string fileName) =>
-            DownloadFileAsync(address, fileName).Wait();
+            FileUtils.DownloadFile(address, fileName);
 
         public IDiagnosticsWriter CreateDiagnosticsWriter(string filename) => new DiagnosticsStream(filename);
 

csharp/extractor/Semmle.Extraction.CSharp.DependencyFetching/NugetPackages.cs

@@ -14,6 +14,26 @@ namespace Semmle.Extraction.CSharp.DependencyFetching
     /// </summary>
     internal class NugetPackages
     {
+        private readonly string nugetExe;
+        private readonly ProgressMonitor progressMonitor;
+
+        /// <summary>
+        /// The list of package files.
+        /// </summary>
+        public FileInfo[] PackageFiles { get; }
+
+        /// <summary>
+        /// The source directory used.
+        /// </summary>
+        public string SourceDirectory { get; }
+
+        /// <summary>
+        /// The computed packages directory.
+        /// This will be in the Temp location
+        /// so as to not trample the source tree.
+        /// </summary>
+        public TemporaryDirectory PackageDirectory { get; }
+
         /// <summary>
         /// Create the package manager for a specified source tree.
         /// </summary>
@@ -32,47 +52,11 @@ public NugetPackages(string sourceDir, TemporaryDirectory packageDirectory, Prog
             if (!File.Exists(nugetExe))
                 throw new FileNotFoundException(string.Format("NuGet could not be found at {0}", nugetExe));
 
-            packages = new DirectoryInfo(SourceDirectory)
+            PackageFiles = new DirectoryInfo(SourceDirectory)
                 .EnumerateFiles("packages.config", SearchOption.AllDirectories)
                 .ToArray();
         }
 
-        // List of package files to download.
-        private readonly FileInfo[] packages;
-
-        /// <summary>
-        /// The list of package files.
-        /// </summary>
-        public IEnumerable<FileInfo> PackageFiles => packages;
-
-        /// <summary>
-        /// Download the packages to the temp folder.
-        /// </summary>
-        /// <param name="pm">The progress monitor used for reporting errors etc.</param>
-        public void InstallPackages()
-        {
-            foreach (var package in packages)
-            {
-                RestoreNugetPackage(package.FullName);
-            }
-        }
-
-        /// <summary>
-        /// The source directory used.
-        /// </summary>
-        public string SourceDirectory
-        {
-            get;
-            private set;
-        }
-
-        /// <summary>
-        /// The computed packages directory.
-        /// This will be in the Temp location
-        /// so as to not trample the source tree.
-        /// </summary>
-        public TemporaryDirectory PackageDirectory { get; }
-
         /// <summary>
         /// Restore all files in a specified package.
         /// </summary>
@@ -133,7 +117,16 @@ private void RestoreNugetPackage(string package)
             }
         }
 
-        private readonly string nugetExe;
-        private readonly ProgressMonitor progressMonitor;
+        /// <summary>
+        /// Download the packages to the temp folder.
+        /// </summary>
+        /// <param name="pm">The progress monitor used for reporting errors etc.</param>
+        public void InstallPackages()
+        {
+            foreach (var package in PackageFiles)
+            {
+                RestoreNugetPackage(package.FullName);
+            }
+        }
     }
 }

csharp/extractor/Semmle.Util/FileUtils.cs

@@ -1,8 +1,10 @@
 using System;
 using System.IO;
 using System.Linq;
+using System.Net.Http;
 using System.Security.Cryptography;
 using System.Text;
+using System.Threading.Tasks;
 
 namespace Semmle.Util
 {
@@ -91,5 +93,20 @@ public static string ComputeFileHash(string filePath)
                 hex.AppendFormat("{0:x2}", b);
             return hex.ToString();
         }
+
+        private static async Task DownloadFileAsync(string address, string filename)
+        {
+            using var httpClient = new HttpClient();
+            using var request = new HttpRequestMessage(HttpMethod.Get, address);
+            using var contentStream = await (await httpClient.SendAsync(request)).Content.ReadAsStreamAsync();
+            using var stream = new FileStream(filename, FileMode.Create, FileAccess.Write, FileShare.None, 4096, true);
+            await contentStream.CopyToAsync(stream);
+        }
+
+        /// <summary>
+        /// Downloads the file at <paramref name="address"/> to <paramref name="fileName"/>.
+        /// </summary>
+        public static void DownloadFile(string address, string fileName) =>
+           DownloadFileAsync(address, fileName).Wait();
     }
 }