fix self update in Debian systems

src/handlers.ts

@@ -1,9 +1,10 @@
-import axios from 'axios'
-import { Writer } from 'clitastic'
-import { unlinkSync } from 'fs'
+import { chmodSync, renameSync, unlinkSync } from 'fs'
 import { tmpdir } from 'os'
 import { join, resolve } from 'path'
 
+import axios from 'axios'
+import { Writer } from 'clitastic'
+
 import { config, INSTALL_DIR, VERSION } from './autorestic'
 import { checkAndConfigureBackends, getBackendsFromLocations, getEnvFromBackend } from './backend'
 import { backupAll } from './backup'
@@ -147,7 +148,7 @@ const handlers: Handlers = {
 			checkIfResticIsAvailable()
 			console.log('Restic is already installed')
 			return
-		} catch (e) {
+		} catch {
 		}
 
 		const w = new Writer('Checking latest version... ⏳')
@@ -164,9 +165,7 @@ const handlers: Handlers = {
 		}
 
 		w.replaceLn('Downloading binary... 🌎')
-		const name = `${json.name.replace(' ', '_')}_${process.platform}_${
-			archMap[process.arch]
-		}.bz2`
+		const name = `${json.name.replace(' ', '_')}_${process.platform}_${archMap[process.arch]}.bz2`
 		const dl = json.assets.find((asset: any) => asset.name === name)
 		if (!dl)
 			return console.log(
@@ -184,8 +183,8 @@ const handlers: Handlers = {
 		unlinkSync(tmp)
 
 		w.replaceLn(`Moving to ${INSTALL_DIR} 🚙`)
-		exec('chmod', ['+x', extracted])
-		exec('mv', [extracted, INSTALL_DIR + '/restic'])
+		chmodSync(extracted, 0o755)
+		renameSync(extracted, INSTALL_DIR + '/restic')
 
 		w.done(
 			`\nFinished! restic is installed under: ${INSTALL_DIR}`.underline + ' 🎉',

src/utils.ts

@@ -1,8 +1,8 @@
 import { spawnSync, SpawnSyncOptions } from 'child_process'
 import { randomBytes } from 'crypto'
-import { createWriteStream } from 'fs'
+import { createWriteStream, unlinkSync, renameSync } from 'fs'
 import { dirname, isAbsolute, join, resolve } from 'path'
-import { homedir } from 'os'
+import { homedir, tmpdir } from 'os'
 
 import axios from 'axios'
 import { Duration, Humanizer } from 'uhrwerk'
@@ -44,13 +44,14 @@ export const execPlain = (command: string, opt: SpawnSyncOptions = {}) => {
 export const checkIfResticIsAvailable = () =>
 	checkIfCommandIsAvailable(
 		'restic',
-		'Restic is not installed'.red +
-		' https://restic.readthedocs.io/en/latest/020_installation.html#stable-releases',
+		'restic is not installed'.red +
+		'\nEither run ' + 'autorestic install'.green +
+		'\nOr go to https://restic.readthedocs.io/en/latest/020_installation.html#stable-releases',
 	)
 
 export const checkIfCommandIsAvailable = (cmd: string, errorMsg?: string) => {
-	if (require('child_process').spawnSync(cmd).error)
-		throw new Error(errorMsg ? errorMsg : `"${errorMsg}" is not installed`.red)
+	if (spawnSync(cmd).error)
+		throw new Error(errorMsg ? errorMsg : `"${cmd}" is not installed`.red)
 }
 
 export const makeObjectKeysLowercase = (object: Object): any =>
@@ -83,11 +84,19 @@ export const downloadFile = async (url: string, to: string) =>
 			responseType: 'stream',
 		})
 
-		const stream = createWriteStream(to)
+		const tmp = join(tmpdir(), rand(64))
+		const stream = createWriteStream(tmp)
 
 		const writer = file.pipe(stream)
 		writer.on('close', () => {
 			stream.close()
+			try {
+				// Delete file if already exists. Needed if the binary wants to replace itself.
+				// Unix does not allow to overwrite a file that is being executed, but you can remove it and save other one at its place
+				unlinkSync(to)
+			} catch {
+			}
+			renameSync(tmp, to)
 			res()
 		})
 	})