WIP: Download local update bundles

completion/_balena

@@ -14,7 +14,7 @@ _balena() {
   app_cmds=( create )
   block_cmds=( create )
   config_cmds=( generate inject read reconfigure write )
-  device_cmds=( deactivate identify init local-mode move os-update pin public-url purge reboot register rename restart rm shutdown start-service stop-service track-fleet )
+  device_cmds=( deactivate download-update identify init local-mode move os-update pin public-url purge reboot register rename restart rm shutdown start-service stop-service track-fleet )
   devices_cmds=( supported )
   env_cmds=( add rename rm )
   fleet_cmds=( create pin purge rename restart rm track-latest )

completion/balena-completion.bash

@@ -13,7 +13,7 @@ _balena_complete()
   app_cmds="create"
   block_cmds="create"
   config_cmds="generate inject read reconfigure write"
-  device_cmds="deactivate identify init local-mode move os-update pin public-url purge reboot register rename restart rm shutdown start-service stop-service track-fleet"
+  device_cmds="deactivate download-update identify init local-mode move os-update pin public-url purge reboot register rename restart rm shutdown start-service stop-service track-fleet"
   devices_cmds="supported"
   env_cmds="add rename rm"
   fleet_cmds="create pin purge rename restart rm track-latest"

docs/balena-cli.md

@@ -196,6 +196,7 @@ are encouraged to regularly update the balena CLI to the latest version.
 - Devices
 
 	- [device deactivate <uuid>](#device-deactivate-uuid)
+	- [device download-update <uuid(s)>](#device-download-update-uuid-s)
 	- [device identify <uuid>](#device-identify-uuid)
 	- [device <uuid>](#device-uuid)
 	- [device init](#device-init)
@@ -1218,6 +1219,26 @@ the UUID of the device to be deactivated
 
 answer "yes" to all questions (non interactive use)
 
+## device download-update <uuid(s)>
+
+
+
+Examples:
+
+	$ balena device download-update fd3a6a1,e573ad5
+
+### Arguments
+
+#### UUIDS
+
+comma-separated list (no blank spaces) of device UUIDs
+
+### Options
+
+#### -o, --output OUTPUT
+
+output path
+
 ## device identify <uuid>
 
 Identify a device by making the ACT LED blink (Raspberry Pi).

package.json

@@ -196,6 +196,7 @@
     "@balena/dockerignore": "^1.0.2",
     "@balena/env-parsing": "^1.1.8",
     "@balena/es-version": "^1.0.1",
+    "@balena/update-bundle": "^0.5.0",
     "@oclif/core": "^4.0.8",
     "@resin.io/valid-email": "^0.1.0",
     "@sentry/node": "^6.16.1",

src/commands/device/download-update.ts

@@ -0,0 +1,44 @@
+import { Flags, Args } from '@oclif/core';
+import Command from '../../command';
+import { stripIndent } from '../../utils/lazy';
+import * as cf from '../../utils/common-flags';
+
+import { downloadUpdateBundle } from '../../utils/download-update';
+
+export default class DeviceDownloadUpdateCmd extends Command {
+	public static description = stripIndent`
+		Downloads a device local update bundle.
+	`;
+
+	public static examples = ['$ balena device download-update fd3a6a1,e573ad5'];
+
+	public static args = {
+		uuids: Args.string({
+			description: 'comma-separated list (no blank spaces) of device UUIDs',
+			required: true,
+		}),
+	};
+
+	public static usage = 'device download-update <uuid(s)>';
+
+	public static flags = {
+		output: Flags.string({
+			description: 'output path',
+			char: 'o',
+			required: true,
+		}),
+		help: cf.help,
+	};
+
+	public static authenticated = true;
+
+	public async run() {
+		const { args: params, flags: options } = await this.parse(
+			DeviceDownloadUpdateCmd,
+		);
+
+		// TODO: support UUIDs passed through stdin pipe
+
+		await downloadUpdateBundle(params.uuids, options.output);
+	}
+}

src/utils/download-update.ts

@@ -0,0 +1,114 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import type * as stream from 'stream';
+import * as zlib from 'zlib';
+import { pipeline } from 'stream/promises';
+
+import * as bundle from '@balena/update-bundle';
+
+import { getBalenaSdk } from './lazy';
+
+enum UpdateBundleFormat {
+	CompressedTar,
+	Tar,
+}
+
+export async function downloadUpdateBundle(uuids: string, output: string) {
+	const balena = getBalenaSdk();
+
+	const deviceUuids = await deviceUuidsFromParam(balena, uuids);
+
+	const subject = (await balena.auth.getUserInfo()).username;
+	const token = await balena.auth.getToken();
+
+	const updateBundleStream = await bundle.create({
+		type: 'Device',
+		deviceUuids,
+		auth: {
+			scheme: 'Bearer',
+			subject,
+			token,
+		},
+	});
+
+	// TODO: accept fleet arguments for download update bundle as well
+	/*
+    const updateBundleStream = await bundle.create({
+        type: 'Fleet',
+        appUuid: 'f48afafee22245209acfbaf4c2b482e8',
+        releaseUuid: '65a9cb86a59fbe58430715a3d687ea68',
+        auth: {
+            scheme: 'Bearer',
+            subject,
+            token,
+        },
+    });
+    */
+
+	await saveBundle(updateBundleStream, output);
+}
+
+async function saveBundle(
+	updateBundleStream: stream.Readable,
+	filePath: string,
+) {
+	const target = fs.createWriteStream(filePath);
+
+	const format = getUpdateBundleFormat(filePath);
+
+	if (format === UpdateBundleFormat.CompressedTar) {
+		const gzip = zlib.createGzip();
+
+		await pipeline(updateBundleStream, gzip, target);
+	} else {
+		await pipeline(updateBundleStream, target);
+	}
+}
+
+function getUpdateBundleFormat(filePath: string): UpdateBundleFormat {
+	const ext = getCompoundExtension(filePath);
+
+	if (ext === '.tar.gz' || ext === '.tgz') {
+		return UpdateBundleFormat.CompressedTar;
+	} else if (ext === '.tar') {
+		return UpdateBundleFormat.Tar;
+	} else {
+		throw new Error(`Unsupported file extension: ${ext}`);
+	}
+}
+
+function getCompoundExtension(filePath: string): string {
+	let compoundExt = '';
+	let currentPath = filePath;
+
+	for (;;) {
+		const ext = path.extname(currentPath);
+		if (ext === '') {
+			break;
+		}
+		compoundExt = ext + compoundExt;
+		currentPath = path.basename(currentPath, ext);
+	}
+
+	return compoundExt;
+}
+
+async function deviceUuidsFromParam(
+	balena: ReturnType<typeof getBalenaSdk>,
+	uuids: string,
+): Promise<string[]> {
+	const uuidsList = uuids.split(',');
+
+	const deviceUuids = [];
+	for (const uuid of uuidsList) {
+		try {
+			const device = await balena.models.device.get(uuid);
+			deviceUuids.push(device.uuid);
+		} catch (err) {
+			// TODO: Needs proper error handling
+			throw new Error(`UUID error ${uuid}: ${err.message}`);
+		}
+	}
+
+	return deviceUuids;
+}