finished unit tests and docstrings

MalwareMultiScan.Backends/Backends/Abstracts/AbstractLocalProcessScanBackend.cs

@@ -1,77 +1,64 @@
 using System;
-using System.Diagnostics;
-using System.IO;
 using System.Linq;
 using System.Text.RegularExpressions;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Extensions.Logging;
+using MalwareMultiScan.Backends.Services.Interfaces;
 
 namespace MalwareMultiScan.Backends.Backends.Abstracts
 {
+    /// <inheritdoc />
     public abstract class AbstractLocalProcessScanBackend : AbstractScanBackend
     {
-        private readonly ILogger _logger;
+        private readonly IProcessRunner _processRunner;
 
-        protected AbstractLocalProcessScanBackend(ILogger logger)
+        /// <inheritdoc />
+        protected AbstractLocalProcessScanBackend(IProcessRunner processRunner)
         {
-            _logger = logger;
+            _processRunner = processRunner;
         }
 
+        /// <summary>
+        /// Regex to extract names of threats.
+        /// </summary>
         protected abstract Regex MatchRegex { get; }
+        
+        /// <summary>
+        /// Path to the backend.
+        /// </summary>
         protected abstract string BackendPath { get; }
+        
+        /// <summary>
+        /// Parse StdErr instead of StdOut.
+        /// </summary>
         protected virtual bool ParseStdErr { get; } = false;
+        
+        /// <summary>
+        /// Throw on non-zero exit code.
+        /// </summary>
         protected virtual bool ThrowOnNonZeroExitCode { get; } = true;
 
+        /// <summary>
+        /// Get backend process parameters.
+        /// </summary>
+        /// <param name="path">Path to the temporary file.</param>
+        /// <returns>Formatted string with parameters and path.</returns>
         protected abstract string GetBackendArguments(string path);
-
-        public override async Task<string[]> ScanAsync(string path, CancellationToken cancellationToken)
+        
+        /// <inheritdoc />
+        public override Task<string[]> ScanAsync(string path, CancellationToken cancellationToken)
         {
-            var process = new Process
-            {
-                StartInfo = new ProcessStartInfo(BackendPath, GetBackendArguments(path))
-                {
-                    RedirectStandardError = true,
-                    RedirectStandardOutput = true,
-                    WorkingDirectory = Path.GetDirectoryName(BackendPath) ?? Directory.GetCurrentDirectory()
-                }
-            };
+            var exitCode = _processRunner.RunTillCompletion(BackendPath, GetBackendArguments(path), cancellationToken,
+                out var standardOutput, out var standardError);
 
-            _logger.LogInformation(
-                $"Starting process {process.StartInfo.FileName} " +
-                $"with arguments {process.StartInfo.Arguments} " +
-                $"in working directory {process.StartInfo.WorkingDirectory}");
+            if (ThrowOnNonZeroExitCode && exitCode != 0)
+                throw new ApplicationException($"Process has terminated with an exit code {exitCode}");
 
-            process.Start();
-
-            cancellationToken.Register(() =>
-            {
-                if (process.HasExited)
-                    return;
-                
-                process.Kill(true);
-                
-                throw new TimeoutException("Scanning failed to complete within the timeout");
-            });
-
-            process.WaitForExit();
-
-            _logger.LogInformation($"Process has exited with code {process.ExitCode}");
-
-            var standardOutput = await process.StandardOutput.ReadToEndAsync();
-            var standardError = await process.StandardError.ReadToEndAsync();
-
-            _logger.LogDebug($"Process standard output: {standardOutput}");
-            _logger.LogDebug($"Process standard error: {standardError}");
-
-            if (ThrowOnNonZeroExitCode && process.ExitCode != 0)
-                throw new ApplicationException($"Process has terminated with an exit code {process.ExitCode}");
-
-            return MatchRegex
+            return Task.FromResult(MatchRegex
                 .Matches(ParseStdErr ? standardError : standardOutput)
                 .Where(x => x.Success)
                 .Select(x => x.Groups["threat"].Value)
-                .ToArray();
+                .ToArray());
         }
     }
 }