Cancel, Retry, and Warning download UI

src/electron/ipc/download/DownloadHandler.ts

@@ -4,7 +4,7 @@ import { createHash, randomBytes as _randomBytes } from 'crypto'
 import { tempPath } from '../../shared/Paths'
 import { promisify } from 'util'
 import { join } from 'path'
-import { Download, NewDownload } from '../../shared/interfaces/download.interface'
+import { Download, NewDownload, DownloadProgress } from '../../shared/interfaces/download.interface'
 import { emitIPCEvent } from '../../main'
 import { mkdir as _mkdir } from 'fs'
 import { FileExtractor } from './FileExtractor'
@@ -13,16 +13,29 @@ import { sanitizeFilename, interpolate } from '../../shared/UtilFunctions'
 const randomBytes = promisify(_randomBytes)
 const mkdir = promisify(_mkdir)
 
-export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
-  event: 'add-download' = 'add-download'
+export class DownloadHandler implements IPCEmitHandler<'download'> {
+  event: 'download' = 'download'
 
-  async handler(data: NewDownload) {
-    const download: Download = {
+  // TODO: replace needle with got (for cancel() method) (if before-headers event is possible?)
+
+  downloadCallbacks: { [versionID: number]: { cancel: () => void, retry: () => void, continue: () => void } } = {}
+
+  async handler(data: Download) {
+    switch (data.action) {
+      case 'cancel': this.downloadCallbacks[data.versionID].cancel(); return
+      case 'retry': this.downloadCallbacks[data.versionID].retry(); return
+      case 'continue': this.downloadCallbacks[data.versionID].continue(); return
+      case 'add': this.downloadCallbacks[data.versionID] = { cancel: () => { }, retry: () => { }, continue: () => { } }
+    }
+
+    // data.action == add; data.data should be defined
+    const download: DownloadProgress = {
       versionID: data.versionID,
-      title: `${data.avTagName} - ${data.artist}`,
+      title: `${data.data.avTagName} - ${data.data.artist}`,
       header: '',
       description: '',
-      percent: 0
+      percent: 0,
+      type: 'good'
     }
     const randomString = (await randomBytes(5)).toString('hex')
     const chartPath = join(tempPath, `chart_${randomString}`)
@@ -30,17 +43,19 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
 
     let allFilesProgress = 0
     // Only iterate over the keys in data.links that have link values (not hashes)
-    const fileKeys = Object.keys(data.links).filter(link => data.links[link].includes('.'))
+    const fileKeys = Object.keys(data.data.links).filter(link => data.data.links[link].includes('.'))
     const individualFileProgressPortion = 80 / fileKeys.length
     for (let i = 0; i < fileKeys.length; i++) {
-      const typeHash = createHash('md5').update(data.links[fileKeys[i]]).digest('hex')
-      const downloader = new FileDownloader(data.links[fileKeys[i]], chartPath, data.links[typeHash])
+      const typeHash = createHash('md5').update(data.data.links[fileKeys[i]]).digest('hex')
+      const downloader = new FileDownloader(data.data.links[fileKeys[i]], chartPath, data.data.links[typeHash])
+      this.downloadCallbacks[data.versionID].cancel = () => downloader.cancelDownload() // Make cancel button cancel this download
       let fileProgress = 0
 
       let waitTime: number
       downloader.on('wait', (_waitTime) => {
         download.header = `[${fileKeys[i]}] (file ${i + 1}/${fileKeys.length})`
         download.description = `Waiting for Google rate limit... (${_waitTime}s)`
+        download.type = 'good'
         waitTime = _waitTime
       })
 
@@ -48,6 +63,7 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
         download.description = `Waiting for Google rate limit... (${secondsRemaining}s)`
         fileProgress = interpolate(secondsRemaining, waitTime, 0, 0, individualFileProgressPortion / 2)
         download.percent = allFilesProgress + fileProgress
+        download.type = 'good'
         emitIPCEvent('download-updated', download)
       })
 
@@ -55,13 +71,15 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
         download.description = `Sending request...`
         fileProgress = individualFileProgressPortion / 2
         download.percent = allFilesProgress + fileProgress
+        download.type = 'good'
         emitIPCEvent('download-updated', download)
       })
 
       downloader.on('warning', (continueAnyway) => {
         download.description = 'WARNING'
+        this.downloadCallbacks[data.versionID].continue = continueAnyway
+        download.type = 'warning'
         emitIPCEvent('download-updated', download)
-        //TODO: continue anyway
       })
 
       let filesize = -1
@@ -73,6 +91,7 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
         } else {
           download.description = `Downloading... (0 MB)`
         }
+        download.type = 'good'
         emitIPCEvent('download-updated', download)
       })
 
@@ -85,14 +104,16 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
           download.description = `Downloading... (${Math.round(bytesDownloaded / 1e+5) / 10} MB)`
           download.percent = allFilesProgress + fileProgress
         }
+        download.type = 'good'
         emitIPCEvent('download-updated', download)
       })
 
       downloader.on('error', (error, retry) => {
         download.header = error.header
         download.description = error.body
+        download.type = 'error'
+        this.downloadCallbacks[data.versionID].retry = retry
         emitIPCEvent('download-updated', download)
-        // TODO: retry
       })
 
       // Wait for the 'complete' event before moving on to another file download
@@ -107,14 +128,16 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
       })
     }
 
-    const destinationFolderName = sanitizeFilename(`${data.artist} - ${data.avTagName} (${data.charter})`)
+    const destinationFolderName = sanitizeFilename(`${data.data.artist} - ${data.data.avTagName} (${data.data.charter})`)
     const extractor = new FileExtractor(chartPath, fileKeys.includes('archive'), destinationFolderName)
+    this.downloadCallbacks[data.versionID].cancel = () => extractor.cancelExtract()
 
     let archive = ''
     extractor.on('extract', (filename) => {
       archive = filename
       download.header = `[${archive}]`
       download.description = `Extracting...`
+      download.type = 'good'
       emitIPCEvent('download-updated', download)
     })
 
@@ -122,6 +145,7 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
       download.header = `[${archive}] (${filecount} file${filecount == 1 ? '' : 's'} extracted)`
       download.description = `Extracting... (${percent}%)`
       download.percent = interpolate(percent, 0, 100, 80, 95)
+      download.type = 'good'
       emitIPCEvent('download-updated', download)
     })
 
@@ -129,6 +153,7 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
       download.header = `Moving files to library folder...`
       download.description = filepath
       download.percent = 95
+      download.type = 'good'
       emitIPCEvent('download-updated', download)
     })
 
@@ -136,14 +161,16 @@ export class AddDownloadHandler implements IPCEmitHandler<'add-download'> {
       download.header = `Download complete.`
       download.description = filepath
       download.percent = 100
+      download.type = 'good'
       emitIPCEvent('download-updated', download)
     })
 
     extractor.on('error', (error, retry) => {
       download.header = error.header
       download.description = error.body
+      download.type = 'error'
+      this.downloadCallbacks[data.versionID].retry = retry
       emitIPCEvent('download-updated', download)
-      // TODO: retry
     })
 
     extractor.beginExtract()

src/electron/ipc/download/FileDownloader.ts

@@ -19,12 +19,13 @@ export type DownloadError = { header: string, body: string }
 
 export class FileDownloader {
   private RATE_LIMIT_DELAY: number
-  private readonly RETRY_MAX = 3
+  private readonly RETRY_MAX = 2
   private static waitTime = 0
   private static clock: NodeJS.Timer
 
   private callbacks = {} as Callbacks
   private retryCount: number
+  private wasCanceled = false
 
   constructor(private url: string, private destinationFolder: string, private expectedHash?: string) {
     if (FileDownloader.clock == undefined) {
@@ -60,6 +61,7 @@ export class FileDownloader {
     }
     this.callbacks.wait(waitTime)
     const clock = setInterval(() => {
+      if (this.wasCanceled) { clearInterval(clock); return } // CANCEL POINT
       waitTime--
       this.callbacks.waitProgress(waitTime)
       if (waitTime <= 0) {
@@ -75,10 +77,12 @@ export class FileDownloader {
    * @param cookieHeader the "cookie=" header to include this request.
    */
   private requestDownload(cookieHeader?: string) {
+    if (this.wasCanceled) { return } // CANCEL POINT
     this.callbacks.request()
     let uuid = generateUUID()
     const req = needle.get(this.url, {
       follow_max: 10,
+      open_timeout: 5000,
       headers: Object.assign({
         'User-Agent': 'PostmanRuntime/7.22.0',
         'Referer': this.url,
@@ -99,12 +103,12 @@ export class FileDownloader {
       }
     })
 
-    req.on('err', (err) => {
-      // TODO: this is called on timeout; if there are other cases where this can fail, they should be printed correctly
-      // this.callbacks.error({ header: 'Error', description: `${err}` }, () => this.beginDownload())
+    req.on('err', (err: Error) => {
+      this.callbacks.error({ header: 'Connection Error', body: `${err.name}: ${err.message}` }, () => this.beginDownload())
     })
 
     req.on('header', (statusCode, headers: Headers) => {
+      if (this.wasCanceled) { return } // CANCEL POINT
       if (statusCode != 200) {
         this.callbacks.error({ header: 'Connection failed', body: `Server returned status code: ${statusCode}` }, () => this.beginDownload())
         return
@@ -117,10 +121,10 @@ export class FileDownloader {
         const fileName = this.getDownloadFileName(headers)
         const downloadHash = this.getDownloadHash(headers)
         if (this.expectedHash !== undefined && downloadHash !== this.expectedHash) {
+          req.pause()
           this.callbacks.warning(() => {
-            //TODO: check if this will actually work (or will the data get lost in the time before the button is clicked?)
-            // Maybe show the message at the end, and ask if they want to keep it.
             this.handleDownloadResponse(req, fileName, headers['content-length'])
+            req.resume()
           })
         } else {
           this.handleDownloadResponse(req, fileName, headers['content-length'])
@@ -220,4 +224,8 @@ export class FileDownloader {
       return headers['x-goog-hash']
     }
   }
+
+  cancelDownload() {
+    this.wasCanceled = true
+  }
 }

src/electron/ipc/download/FileExtractor.ts

@@ -29,6 +29,7 @@ export class FileExtractor {
 
   private callbacks = {} as Callbacks
   private libraryFolder: string
+  private wasCanceled = false
   constructor(private sourceFolder: string, private isArchive: boolean, private destinationFolderName: string) { }
 
   /**
@@ -58,6 +59,7 @@ export class FileExtractor {
    * @param filename The name of the archive file.
    */
   private extract(filename: string) {
+    if (this.wasCanceled) { return } // CANCEL POINT
     this.callbacks.extract(filename)
     const source = join(this.sourceFolder, filename)
 
@@ -93,6 +95,7 @@ export class FileExtractor {
    * Deletes the archive at <archiveFilepath>, then transfers the extracted chart to <this.libraryFolder>.
    */
   private async transfer(archiveFilepath?: string) {
+    if (this.wasCanceled) { return } // CANCEL POINT
     try {
       
       // Create destiniation folder if it doesn't exist
@@ -117,6 +120,8 @@ export class FileExtractor {
         files = await readdir(this.sourceFolder)
       }
 
+      if (this.wasCanceled) { return } // CANCEL POINT
+
       // Copy the files from the temporary directory to the destination
       for (const file of files) {
         await copyFile(join(this.sourceFolder, file), join(destinationFolder, file))
@@ -133,4 +138,8 @@ export class FileExtractor {
       this.callbacks.error({ header: 'Transfer Failed', body: `Unable to transfer downloaded files to the library folder: ${e.name}` }, undefined)
     }
   }
+
+  cancelExtract() {
+    this.wasCanceled = true
+  }
 }

src/electron/shared/Database.ts

@@ -37,6 +37,7 @@ export default class Database {
       }
     })
 
+    // TODO: make this error message more user-friendly (retry option?)
     return new Promise<void>((resolve, reject) => {
       this.conn.connect(err => {
         if (err) {

src/electron/shared/IPCHandler.ts

@@ -3,8 +3,8 @@ import { VersionResult, AlbumArtResult } from './interfaces/songDetails.interfac
 import SearchHandler from '../ipc/SearchHandler.ipc'
 import SongDetailsHandler from '../ipc/SongDetailsHandler.ipc'
 import AlbumArtHandler from '../ipc/AlbumArtHandler.ipc'
-import { Download, NewDownload } from './interfaces/download.interface'
-import { AddDownloadHandler } from '../ipc/download/AddDownloadHandler'
+import { Download, NewDownload, DownloadProgress } from './interfaces/download.interface'
+import { DownloadHandler } from '../ipc/download/DownloadHandler'
 import { Settings } from './Settings'
 import InitSettingsHandler from '../ipc/InitSettingsHandler.ipc'
 
@@ -51,13 +51,13 @@ export interface IPCInvokeHandler<E extends keyof IPCInvokeEvents> {
 
 export function getIPCEmitHandlers(): IPCEmitHandler<keyof IPCEmitEvents>[]{
   return [
-    new AddDownloadHandler()
+    new DownloadHandler()
   ]
 }
 
 export type IPCEmitEvents = {
-  'add-download': NewDownload
-  'download-updated': Download
+  'download': Download
+  'download-updated': DownloadProgress
 }
 
 export interface IPCEmitHandler<E extends keyof IPCEmitEvents> {

src/electron/shared/interfaces/download.interface.ts

@@ -1,8 +1,13 @@
+export interface Download {
+  action: 'add' | 'retry' | 'continue' | 'cancel'
+  versionID: number
+  data ?: NewDownload
+}
+
 /**
  * Contains the data required to start downloading a single chart
  */
 export interface NewDownload {
-  versionID: number
   avTagName: string
   artist: string
   charter: string
@@ -12,10 +17,11 @@ export interface NewDownload {
 /**
  * Represents the download progress of a single chart
  */
-export interface Download {
+export interface DownloadProgress {
   versionID: number
   title: string
   header: string
   description: string
   percent: number
+  type: 'good' | 'warning' | 'error' | 'cancel'
 }