Fixing download progress status (#557)

* refactoring the download code to make it more testable

* adding more test for download provider

src/languageservice/decompressProvider.ts

@@ -0,0 +1,24 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+'use strict';
+
+import {IDecompressProvider, IPackage} from './interfaces';
+import  {ILogger} from '../models/interfaces';
+const decompress = require('decompress');
+
+export default class DecompressProvider implements IDecompressProvider {
+    public decompress(pkg: IPackage, logger: ILogger): Promise<void> {
+        return new Promise<void>((resolve, reject) => {
+            decompress(pkg.tmpFile.name, pkg.installPath).then(files => {
+                    logger.appendLine(`Done! ${files.length} files unpacked.\n`);
+                    resolve();
+                }).catch(decompressErr => {
+                        logger.appendLine(`[ERROR] ${decompressErr}`);
+                        reject(decompressErr);
+                });
+        });
+    }
+}

src/languageservice/httpClient.ts

@@ -0,0 +1,145 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+'use strict';
+import {IPackage, IStatusView, PackageError, IHttpClient} from './interfaces';
+import  {ILogger} from '../models/interfaces';
+import {parse as parseUrl, Url} from 'url';
+import * as https from 'https';
+import * as http from 'http';
+import {getProxyAgent} from './proxy';
+
+let fs = require('fs');
+
+/*
+ * Http client class to handle downloading files using http or https urls
+ */
+export default class HttpClient implements IHttpClient {
+
+   /*
+    * Downloads a file and stores the result in the temp file inside the package object
+    */
+    public downloadFile(urlString: string, pkg: IPackage, logger: ILogger, statusView: IStatusView, proxy?: string, strictSSL?: boolean): Promise<void> {
+        const url = parseUrl(urlString);
+        let options = this.getHttpClientOptions(url, proxy, strictSSL);
+        let client = url.protocol === 'http:' ? http : https;
+
+        return new Promise<void>((resolve, reject) => {
+            if (!pkg.tmpFile || pkg.tmpFile.fd === 0) {
+                return reject(new PackageError('Temporary package file unavailable', pkg));
+            }
+
+            let request = client.request(options, response => {
+                if (response.statusCode === 301 || response.statusCode === 302) {
+                    // Redirect - download from new location
+                    return resolve(this.downloadFile(response.headers.location, pkg, logger, statusView, proxy, strictSSL));
+                }
+
+                if (response.statusCode !== 200) {
+                    // Download failed - print error message
+                    logger.appendLine(`failed (error code '${response.statusCode}')`);
+                    return reject(new PackageError(response.statusCode.toString(), pkg));
+                }
+
+                // If status code is 200
+                this.handleSuccessfulResponse(pkg, response, logger, statusView).then(_ => {
+                    resolve();
+                }).catch(err => {
+                    reject(err);
+                });
+            });
+
+            request.on('error', error => {
+                reject(new PackageError(`Request error: ${error.code || 'NONE'}`, pkg, error));
+            });
+
+            // Execute the request
+            request.end();
+        });
+    }
+
+    private getHttpClientOptions(url: Url, proxy?: string, strictSSL?: boolean): any {
+        const agent = getProxyAgent(url, proxy, strictSSL);
+
+        let options: http.RequestOptions = {
+            host: url.hostname,
+            path: url.path,
+            agent: agent,
+            port: +url.port
+        };
+
+        if (url.protocol === 'https:') {
+            let httpsOptions: https.RequestOptions = {
+                    host: url.hostname,
+                    path: url.path,
+                    agent: agent,
+                    port: +url.port
+            };
+            options = httpsOptions;
+        }
+
+        return options;
+    }
+
+   /*
+    * Calculate the download percentage and stores in the progress object
+    */
+    public handleDataReceivedEvent(progress: IDownloadProgress, data: any, logger: ILogger, statusView: IStatusView): void {
+        progress.downloadedBytes += data.length;
+
+        // Update status bar item with percentage
+        if (progress.packageSize > 0) {
+            let newPercentage = Math.ceil(100 * (progress.downloadedBytes / progress.packageSize));
+            if (newPercentage !== progress.downloadPercentage) {
+                statusView.updateServiceDownloadingProgress(progress.downloadPercentage);
+                progress.downloadPercentage = newPercentage;
+            }
+
+            // Update dots after package name in output console
+            let newDots = Math.ceil(progress.downloadPercentage / 5);
+            if (newDots > progress.dots) {
+                logger.append('.'.repeat(newDots - progress.dots));
+                progress.dots = newDots;
+            }
+        }
+        return;
+    }
+
+    private handleSuccessfulResponse(pkg: IPackage, response: http.IncomingMessage, logger: ILogger, statusView: IStatusView): Promise<void> {
+        return new Promise<void>((resolve, reject) => {
+            let progress: IDownloadProgress = {
+                packageSize: parseInt(response.headers['content-length'], 10),
+                dots: 0,
+                downloadedBytes: 0,
+                downloadPercentage: 0
+            };
+            logger.append(`(${Math.ceil(progress.packageSize / 1024)} KB) `);
+            response.on('data', data => {
+                this.handleDataReceivedEvent(progress, data, logger, statusView);
+            });
+            let tmpFile = fs.createWriteStream(undefined, { fd: pkg.tmpFile.fd });
+            response.on('end', () => {
+                resolve();
+            });
+
+            response.on('error', err => {
+                reject(new PackageError(`Response error: ${err.code || 'NONE'}`, pkg, err));
+            });
+
+            // Begin piping data from the response to the package file
+            response.pipe(tmpFile, { end: false });
+        });
+    }
+}
+
+/*
+ * Interface to store the values needed to calculate download percentage
+ */
+interface IDownloadProgress {
+    packageSize: number;
+    downloadedBytes: number;
+    downloadPercentage: number;
+    dots: number;
+}