async function _extractAdvinst(sourceMsi: string): Promise<string> {
  console.log(taskLib.loc("AI_ExtractTool"));

  // Ensure the c:\windows\installer folder exists. MSIEXEC will fail on some clients (E.g. Hosted VS2017)
  // due to the lack of this folder.

  let windowsInstallerFolder = path.join(taskLib.getVariable('windir'), 'Installer');
  if (!taskLib.exist(windowsInstallerFolder)) {
    taskLib.debug(taskLib.loc("AI_CreateInstallerFolder"))
    taskLib.mkdirP(windowsInstallerFolder);
  }

  let advinstWorkFolder = path.join(_getAgentTemp(), 'AdvancedInstaller');
  let msiExtractionPath: string = path.join(advinstWorkFolder, 'resources');
  // Create the work folder, otherwise msiexec will fail because of the log path.
  if (!taskLib.exist(advinstWorkFolder))
    taskLib.mkdirP(advinstWorkFolder);
  let msiLogPath: string = path.join(advinstWorkFolder, 'advinst_install.log');

  let msiexecArguments: string[] = ['/a', sourceMsi, 'TARGETDIR=' + msiExtractionPath, '/qn', '/l*v', msiLogPath];

  let exitCode = taskLib.execSync('msiexec.exe', msiexecArguments).code;
  if (exitCode != 0) {
    taskLib.command('task.uploadfile', {}, msiLogPath);
    return null;
  }
  return msiExtractionPath;
}

		feedConnection.getCoreApi().restClient.get(packageUrl, ApiVersion, null, { responseIsCollection: false }, async function (error, status, result) {
			if (!!error || status != 200) {
				return reject(tl.loc("FailedToGetPackageMetadata", error));
			}

			var packageType = result.protocolType.toLowerCase();
			var packageName = result.name;

			if (packageType == "nuget") {
				
				var getDownloadUrlPromise = getDownloadUrl(packageConnection.getCoreApi().vsoClient, feedId, packageName, version)
				getDownloadUrlPromise.catch((error) => {
					return reject(error)
				});
				var downloadUrl = await getDownloadUrlPromise;
				
				if (!tl.exist(downloadPath)) {
					tl.mkdirP(downloadPath);
				}

				var zipLocation = path.resolve(downloadPath, "../", packageName) + ".zip";
				var unzipLocation = path.join(downloadPath, "");

				console.log(tl.loc("StartingDownloadOfPackage", packageName, zipLocation));
				
				var downloadNugetPackagePromise = downloadNugetPackage(packageConnection.getCoreApi(), downloadUrl, zipLocation);
				downloadNugetPackagePromise.catch((error) => {
					return reject(error)
				});
				await downloadNugetPackagePromise;

				console.log(tl.loc("ExtractingNugetPackage", packageName, unzipLocation));

				var unzipPromise = unzip(zipLocation, unzipLocation);
				unzipPromise.catch((error) => {
					return reject(error)
				});
				await unzipPromise;
				
				if (tl.exist(zipLocation)) {
					tl.rmRF(zipLocation);
				}

				return resolve();
			}
			else {
				return reject(tl.loc("PackageTypeNotSupported"));
			}
		});

    public isVersionInstalled(version: string): boolean {
        if (!toolLib.isExplicitVersion(version)) {
            throw tl.loc("ExplicitVersionRequired", version);
        }

        var isInstalled: boolean = false;
        if (this.packageType == utils.Constants.sdk) {
            isInstalled = tl.exist(path.join(this.installationPath, utils.Constants.relativeSdkPath, version)) && tl.exist(path.join(this.installationPath, utils.Constants.relativeSdkPath, `${version}.complete`));
        }
        else {
            isInstalled = tl.exist(path.join(this.installationPath, utils.Constants.relativeRuntimePath, version)) && tl.exist(path.join(this.installationPath, utils.Constants.relativeRuntimePath, `${version}.complete`));
        }

        isInstalled ? console.log(tl.loc("VersionFoundInCache", version)) : console.log(tl.loc("VersionNotFoundInCache", version));
        return isInstalled;
    }

export function saveFileWithName(file: string, name: string, filePath: string): void {
    if (file && tl.exist(file)) {
        const destination = path.join(filePath, name + '.npmrc');
        tl.debug(tl.loc('SavingFile', file));
        copyFile(file, destination);
    }
}

export async function deleteKeychain(keychainPath: string): Promise<void> {
    if (tl.exist(keychainPath)) {
        let deleteKeychainCommand: ToolRunner = tl.tool(tl.which('security', true));
        deleteKeychainCommand.arg(['delete-keychain', keychainPath]);
        await deleteKeychainCommand.exec();
    }
}

export function getAllNpmRegistries(npmrcPath: string): string[] {
    if (tl.exist(npmrcPath)) {
        return NpmrcParser.GetRegistries(npmrcPath, /* saveNormalizedRegistries */ false);
    }

    return [];
}

    private isLatestInstalledVersion(version: string): boolean {
        var pathTobeChecked = this.packageType == utils.Constants.sdk ? path.join(this.installationPath, utils.Constants.relativeSdkPath) : path.join(this.installationPath, utils.Constants.relativeRuntimePath);
        if (!tl.exist(pathTobeChecked)) {
            throw tl.loc("PathNotFoundException", pathTobeChecked);
        }

        var allEnteries: string[] = tl.ls("", [pathTobeChecked]).map(name => path.join(pathTobeChecked, name));
        var folderPaths: string[] = allEnteries.filter(element => fs.lstatSync(element).isDirectory());
        var isLatest: boolean = folderPaths.findIndex(folderPath => {
            try {
                let versionFolderName = path.basename(folderPath);
                tl.debug(tl.loc("ComparingInstalledFolderVersions", version, versionFolderName));
                return utils.versionCompareFunction(versionFolderName, version) > 0;
            }
            catch (ex) {
                // no op, folder name might not be in version format
            }
        }) < 0;

        var filePaths: string[] = allEnteries.filter(element => !fs.lstatSync(element).isDirectory());
        isLatest = isLatest && filePaths.findIndex(filePath => {
            try {
                var versionCompleteFileName = this.getVersionCompleteFileName(path.basename(filePath));
                tl.debug(tl.loc("ComparingInstalledFileVersions", version, versionCompleteFileName));
                return utils.versionCompareFunction(versionCompleteFileName, version) > 0
            }
            catch (ex) {
                // no op, file name might not be in version format
            }
        }) < 0;

        isLatest ? tl.debug(tl.loc("VersionIsLocalLatest", version, this.installationPath)) : tl.debug(tl.loc("VersionIsNotLocalLatest", version, this.installationPath));
        return isLatest;
    }

 /**
  * Delete secure file from the temporary location for the build
  * @param secureFileId
  */
 deleteSecureFile(secureFileId: string): void {
     const tempDownloadPath: string = this.getSecureFileTempDownloadPath(secureFileId);
     if (tl.exist(tempDownloadPath)) {
         tl.debug('Deleting secure file at: ' + tempDownloadPath);
         tl.rmRF(tempDownloadPath);
     }
 }

export function restoreFileWithName(file: string, name: string, filePath: string): void {
    if (file) {
        const source = path.join(filePath, name + '.npmrc');
        if (tl.exist(source)) {
            tl.debug(tl.loc('RestoringFile', file));
            copyFile(source, file);
            tl.rmRF(source);
        }
    }
}

export function saveFile(file: string): void {
    if (file && tl.exist(file)) {
        const tempPath = getTempPath();
        const baseName = path.basename(file);
        const destination = path.join(tempPath, baseName);

        tl.debug(tl.loc('SavingFile', file));
        copyFile(file, destination);
    }
}