feat(usbboot): add progress property to usbboot scanned drives (#1803)

This commit re-architects the usbboot adapter to prepare the drives in
the background, while emitting scan results every 2s, where each drive
has a `progress` percentage property.

Change-Type: minor
Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>

lib/shared/sdk/usbboot/index.js

@@ -27,6 +27,7 @@ const Bluebird = require('bluebird')
 const debug = require('debug')('sdk:usbboot')
 const usb = require('./usb')
 const protocol = require('./protocol')
+const utils = require('../../utils')
 
 debug.enabled = true
 
@@ -116,6 +117,21 @@ const USBBOOT_CAPABLE_USB_DEVICES = [
 
 ]
 
+/**
+ * @summary Estimated device reboot delay
+ * @type {Number}
+ * @constant
+ */
+const DEVICE_REBOOT_DELAY = 5000
+
+/**
+ * @summary The initial step of the file server usbboot phase
+ * @constant
+ * @type {Number}
+ * @private
+ */
+const DEFAULT_FILE_SERVER_STEP = 1
+
 /**
  * @summary Convert a USB id (e.g. product/vendor) to a string
  * @function
@@ -171,6 +187,9 @@ class USBBootAdapter extends EventEmitter {
 
     /** @type {Object} Blob cache */
     this.blobCache = {}
+
+    /** @type {Object} Progress hash */
+    this.progress = {}
   }
 
   /**
@@ -228,23 +247,97 @@ class USBBootAdapter extends EventEmitter {
     /* eslint-enable lodash/prefer-lodash-method */
 
       // This is the only way we can unique identify devices
-      device.device = `${device.busNumber}:${device.deviceAddress}`
+      device.raw = `${device.busNumber}:${device.deviceAddress}`
 
-      device.displayName = 'Initializing device'
+      const result = {
-      device.description = 'Compute Module'
+        device: device.raw,
-      device.raw = device.device
+        raw: device.raw,
-      device.size = null
+        displayName: 'Initializing device',
-      device.mountpoints = []
+        description: 'Compute Module',
-      device.protected = false
+        size: null,
-      device.system = false
+        mountpoints: [],
-      device.disabled = true
+        protected: false,
-      device.icon = 'loading'
+        system: false,
-      device.vendor = usbIdToString(device.deviceDescriptor.idVendor)
+        disabled: true,
-      device.product = usbIdToString(device.deviceDescriptor.idProduct)
+        icon: 'loading',
-      device.adaptor = exports.name
+        vendor: usbIdToString(device.deviceDescriptor.idVendor),
+        product: usbIdToString(device.deviceDescriptor.idProduct),
+        adaptor: exports.name
+      }
 
+      if (_.isNil(this.progress[result.raw])) {
+        // TODO: Emit an error event if this fails
+        this.prepare(device, {
+          readFile: options.readFile
+        })
+      }
+
+      result.progress = this.progress[result.raw]
+      return result
+
+    // See http://bluebirdjs.com/docs/api/promise.map.html
+    }, {
+      concurrency: 5
+    }).catch((error) => {
+      callback(error)
+    }).then((devices) => {
+      this.emit('devices', devices)
+      callback(null, devices)
+    })
+
+    return this
+  }
+
+  /**
+   * @summary Prepare a usbboot device
+   * @function
+   * @private
+   *
+   * @param {Object} device - node-usb device
+   * @param {Object} options - options
+   * @param {Function} options.readFile - read file function
+   * @returns {Promise}
+   *
+   * @example
+   * const fs = Bluebird.promisifyAll(require('fs'))
+   * const usb = require('usb')
+   * const device = usb.findByIds(0x0a5c, 0x2763)
+   *
+   * adapter.prepare(device, (name) => {
+   *   return fs.readFileAsync(name)
+   * }).then(() => {
+   *   console.log('Done!')
+   * })
+   */
+  prepare (device, options) {
+    /**
+     * @summary Set device progress
+     * @function
+     * @private
+     *
+     * @param {Number} percentage - percentage
+     *
+     * @example
+     * setProgress(90)
+     */
+    const setProgress = (percentage) => {
+      debug(`%c[${device.raw}] -> ${Math.floor(percentage)}%%`, 'color:red;')
+      this.progress[device.raw] = percentage
+    }
+
+    const serialNumberIndex = device.deviceDescriptor.iSerialNumber
+    debug(`Serial number index: ${serialNumberIndex}`)
+    if (serialNumberIndex === USB_DESCRIPTOR_NULL_INDEX) {
+      // eslint-disable-next-line no-magic-numbers
+      setProgress(10)
+    } else {
+      // eslint-disable-next-line no-magic-numbers
+      setProgress(15)
+    }
+
+    return Bluebird.try(() => {
       // We need to open the device in order to access _configDescriptor
-      debug(`Opening device: ${device.device} (${device.vendor}:${device.product})`)
+      debug(`Opening device: ${device.raw}`)
       device.open()
 
       // Ensures we don't wait forever if an issue occurs
@@ -279,33 +372,45 @@ class USBBootAdapter extends EventEmitter {
 
       const endpoint = deviceInterface.endpoint(addresses.endpoint)
 
-      return Bluebird.try(() => {
+      if (serialNumberIndex === USB_DESCRIPTOR_NULL_INDEX) {
-        const serialNumberIndex = device.deviceDescriptor.iSerialNumber
+        return this.queryBlobFromCache(USBBOOT_BOOTCODE_FILE_NAME, options.readFile).then((bootcode) => {
-        debug(`Serial number index: ${serialNumberIndex}`)
+          return USBBootAdapter.writeBootCode(device, endpoint, bootcode)
+        })
+      }
 
-        if (serialNumberIndex === USB_DESCRIPTOR_NULL_INDEX) {
+      debug('Starting file server')
-          return USBBootAdapter.writeBootCode(device, endpoint, _.get(options.files, [
+
-            USBBOOT_BOOTCODE_FILE_NAME
+      const PERCENTAGE_START = 20
-          ]))
+      const PERCENTAGE_TOTAL = 95
+
+      // TODO: Find a way to not hardcode these values, and instead
+      // figure out the correct number for each board on the fly.
+      // This might be possible once we implement proper device
+      // auto-discovery. For now, we assume the worst case scenario.
+      // eslint-disable-next-line no-magic-numbers
+      const STEPS_TOTAL = 38
+
+      return this.startFileServer(device, endpoint, {
+        readFile: options.readFile,
+        progress: (step) => {
+          setProgress((step * (PERCENTAGE_TOTAL - PERCENTAGE_START) / STEPS_TOTAL) + PERCENTAGE_START)
         }
-
+      }).tap(() => {
-        debug('Starting file server')
+        setProgress(utils.PERCENTAGE_MAXIMUM)
-        return this.startFileServer(device, endpoint, options.files)
-      }).return(device).finally(() => {
-        device.close()
       })
-
+    }).return(device).catch({
-    // See http://bluebirdjs.com/docs/api/promise.map.html
+      message: 'LIBUSB_TRANSFER_CANCELLED'
     }, {
-      concurrency: 5
+      message: 'LIBUSB_ERROR_NO_DEVICE'
-    }).catch((error) => {
+    }, _.constant(null)).tap((result) => {
-      callback(error)
+      if (result) {
-    }).then((devices) => {
+        result.close()
-      this.emit('devices', devices)
+      }
-      callback(null, devices)
+    }).finally(() => {
+      return Bluebird.delay(DEVICE_REBOOT_DELAY).then(() => {
+        Reflect.deleteProperty(this.progress, device.raw)
+      })
     })
-
-    return this
   }
 
   /**
@@ -366,7 +471,10 @@ class USBBootAdapter extends EventEmitter {
    *
    * @param {Object} device - node-usb device
    * @param {Object} endpoint - node-usb endpoint
-   * @param {Function} readFile - read file function
+   * @param {Object} options - options
+   * @param {Function} options.readFile - read file function
+   * @param {Function} options.progress - progress function (step)
+   * @param {Number} [step] - current step (used internally)
    * @returns {Promise}
    *
    * @example
@@ -374,14 +482,20 @@ class USBBootAdapter extends EventEmitter {
    * const usb = require('usb')
    * const device = usb.findByIds(0x0a5c, 0x2763)
    *
-   * adapter.startFileServer(device, device.interfaces(0).endpoint(1), (name) => {
+   * adapter.startFileServer(device, device.interfaces(0).endpoint(1), {
-   *   return fs.readFileAsync(name)
+   *   readFile: (name) => {
+   *     return fs.readFileAsync(name)
+   *   },
+   *   progress: (step) => {
+   *     console.log(`Currently on step ${step}`)
+   *   }
    * }).then(() => {
    *   console.log('Done!')
    * })
    */
-  startFileServer (device, endpoint, readFile) {
+  startFileServer (device, endpoint, options, step = DEFAULT_FILE_SERVER_STEP) {
-    debug('Listening for file messages')
+    debug(`Listening for file messages (step ${step})`)
+    options.progress(step)
     return protocol
       .read(device, protocol.FILE_MESSAGE_SIZE)
       .then(protocol.parseFileMessageBuffer)
@@ -411,7 +525,7 @@ class USBBootAdapter extends EventEmitter {
           if (fileMessage.command === protocol.FILE_MESSAGE_COMMANDS.GET_FILE_SIZE) {
             debug(`Getting the size of ${fileMessage.fileName}`)
 
-            return this.queryBlobFromCache(fileMessage.fileName, readFile).then((fileBuffer) => {
+            return this.queryBlobFromCache(fileMessage.fileName, options.readFile).then((fileBuffer) => {
               const fileSize = fileBuffer.length
               debug(`Sending size: ${fileSize}`)
               return protocol.sendBufferSize(device, fileSize)
@@ -427,7 +541,7 @@ class USBBootAdapter extends EventEmitter {
           if (fileMessage.command === protocol.FILE_MESSAGE_COMMANDS.READ_FILE) {
             debug(`Reading ${fileMessage.fileName}`)
 
-            return this.queryBlobFromCache(fileMessage.fileName, readFile).then((fileBuffer) => {
+            return this.queryBlobFromCache(fileMessage.fileName, options.readFile).then((fileBuffer) => {
               return protocol.write(device, endpoint, fileBuffer)
             }).catch({
               code: 'ENOENT'
@@ -441,7 +555,8 @@ class USBBootAdapter extends EventEmitter {
           return Bluebird.reject(new Error(`Unrecognized command: ${fileMessage.command}`))
         }).then(() => {
           debug('Starting again')
-          return this.startFileServer(device, endpoint, readFile)
+          const STEP_INCREMENT = 1
+          return this.startFileServer(device, endpoint, options, step + STEP_INCREMENT)
         })
       })
   }