public Task RestorePackagesAsync()

in src/WebJobs.Script/Description/DotNet/PackageManager.cs [41:117]
63 lines of code
4 McCabe index (conditional complexity)

        public Task<PackageRestoreResult> RestorePackagesAsync()
        {
            var tcs = new TaskCompletionSource<PackageRestoreResult>();

            string projectPath = null;
            string nugetHome = null;
            string nugetFilePath = null;
            string currentLockFileHash = null;
            try
            {
                projectPath = Path.Combine(_functionDirectory, DotNetConstants.ProjectFileName);
                nugetHome = GetNugetPackagesPath();
                nugetFilePath = ResolveNuGetPath();
                currentLockFileHash = GetCurrentLockFileHash(_functionDirectory);

                // Copy the file to a temporary location, which is where we'll be performing our restore from:
                string tempRestoreLocation = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
                string restoreProjectPath = Path.Combine(tempRestoreLocation, Path.GetFileName(projectPath));
                Directory.CreateDirectory(tempRestoreLocation);
                File.Copy(projectPath, restoreProjectPath);

                var startInfo = new ProcessStartInfo
                {
                    FileName = nugetFilePath,
                    RedirectStandardOutput = true,
                    RedirectStandardError = true,
                    CreateNoWindow = true,
                    UseShellExecute = false,
                    ErrorDialog = false,
                    WorkingDirectory = _functionDirectory,
                    Arguments = string.Format(CultureInfo.InvariantCulture, "restore \"{0}\" --packages \"{1}\"", restoreProjectPath, nugetHome)
                };

                startInfo.Environment.Add(EnvironmentSettingNames.DotnetSkipFirstTimeExperience, "true");
                startInfo.Environment.Add(EnvironmentSettingNames.DotnetAddGlobalToolsToPath, "false");
                startInfo.Environment.Add(EnvironmentSettingNames.DotnetNoLogo, "true");

                var process = new Process { StartInfo = startInfo };
                process.ErrorDataReceived += ProcessDataReceived;
                process.OutputDataReceived += ProcessDataReceived;
                process.EnableRaisingEvents = true;

                process.Exited += (s, e) =>
                {
                    string lockFileLocation = Path.Combine(tempRestoreLocation, "obj", DotNetConstants.ProjectLockFileName);
                    if (process.ExitCode == 0 && File.Exists(lockFileLocation))
                    {
                        File.Copy(lockFileLocation, Path.Combine(_functionDirectory, DotNetConstants.ProjectLockFileName), true);
                    }

                    string newLockFileHash = GetCurrentLockFileHash(_functionDirectory);
                    var result = new PackageRestoreResult
                    {
                        IsInitialInstall = string.IsNullOrEmpty(currentLockFileHash),
                        ReferencesChanged = !string.Equals(currentLockFileHash, newLockFileHash),
                    };

                    tcs.SetResult(result);
                    process.Close();
                };

                _logger.PackageManagerStartingPackagesRestore();

                process.Start();

                process.BeginErrorReadLine();
                process.BeginOutputReadLine();
            }
            catch (Exception exc)
            {
                _logger.PackageManagerRestoreFailed(exc, _functionDirectory, projectPath, nugetHome, nugetFilePath, currentLockFileHash);

                tcs.SetException(exc);
            }

            return tcs.Task;
        }