add auto updater with support for timeout, exit handler

bin/now

@@ -2,14 +2,14 @@
 import program from 'commander';
 import Progress from 'progress';
 import copy from '../lib/copy';
+import * as cfg from '../lib/cfg';
 import { resolve } from 'path';
 import login from '../lib/login';
+import checkUpdate from '../lib/check-update';
 import bytes from 'bytes';
 import chalk from 'chalk';
 import Now from '../lib';
-import fs from 'fs';
 import ms from 'ms';
-import os from 'os';
 
 program
 .usage('[options]')
@@ -29,38 +29,37 @@ if (path) {
   path = process.cwd();
 }
 
-let config;
+const debug = !!program.debug;
+const clipboard = !program.noClipboard;
+const config = cfg.read();
+const update = checkUpdate({ debug });
+const exit = (code) => update.then(() => process.exit(code));
 
-try {
-  config = fs.readFileSync(resolve(os.homedir(), '.now.json'), 'utf8');
-  config = JSON.parse(config);
-} catch (err) {}
-
-if (!config || !config.token || program.login) {
+if (!config.token || program.login) {
   login()
   .then((token) => {
     if (program.login) {
       console.log('> Logged in successfully. Token saved in ~/.now.json');
-      process.exit(0);
+      exit(0);
     } else {
       sync(token).catch((err) => {
         error(`Unknown error: ${err.stack}`);
+        exit(1);
       });
     }
   })
   .catch((e) => {
     error(`Authentication error – ${e.message}`);
-    process.exit(1);
+    exit(1);
   });
 } else {
   sync(config.token).catch((err) => {
     error(`Unknown error: ${err.stack}`);
+    exit(1);
   });
 }
 
 async function sync (token) {
-  const debug = !!program.debug;
-  const clipboard = !program.noClipboard;
   const start = Date.now();
 
   console.log(`> Deploying "${path}"`);
@@ -71,6 +70,7 @@ async function sync (token) {
     await now.create(path, { forceNew: program.force });
   } catch (err) {
     handleError(err);
+    return;
   }
 
   const { url } = now;
@@ -92,7 +92,7 @@ async function sync (token) {
     const elapsed_u = ms(new Date() - start_u);
     console.log(`> Sync complete (${bytes(now.syncAmount)}) [${elapsed_u}] `);
     now.close();
-    process.exit(0);
+    exit(0);
   };
 
   if (now.syncAmount) {
@@ -118,24 +118,26 @@ async function sync (token) {
     now.on('error', (err) => {
       error('Upload failed');
       handleError(err);
-      process.exit(1);
+      exit(1);
     });
   } else {
     console.log('> Sync complete (cached)');
     now.close();
-    process.exit(0);
+    exit(0);
   }
 }
 
 function handleError (err) {
   if (403 === err.status) {
     error('Authentication error. Run `now -L` or `now --login` to log-in again.');
+  } else if (err.userError) {
+    error(err.message);
   } else if (500 === err.status) {
     error('Unexpected server error. Please retry.');
   } else {
     error(`Unexpected error. Please try later. (${err.message})`);
   }
-  process.exit(1);
+  exit(1);
 }
 
 function error (err) {

lib/check-update.js

@@ -0,0 +1,115 @@
+import ms from 'ms';
+import * as cfg from './cfg';
+import pkg from '../../package'; // relative to `build/` :\
+import request from 'https';
+import chalk from 'chalk';
+
+const TEN_MINUTES = ms('1s');
+
+/**
+ * Configures auto updates.
+ * Sets up a `exit` listener to report them.
+ */
+
+export default function checkUpdate (opts = {}) {
+  let updateData;
+
+  const update = check(opts).then((data) => {
+    updateData = data;
+
+    // forces the `exit` event upon Ctrl + C
+    process.on('SIGINT', () => {
+      // clean up output after ^C
+      process.stdout.write('\n');
+      process.exit(1);
+    });
+  }, (err) => console.error(err.stack));
+
+  process.on('exit', (code) => {
+    if (updateData) {
+      const { current, latest, at } = updateData;
+      const ago = ms(Date.now() - at);
+      console.log(`> ${chalk.white.bgRed('UPDATE NEEDED')} ` +
+        `Current: ${current} – ` +
+        `Latest ${chalk.bold(latest)} (released ${ago} ago)`);
+    }
+  });
+
+  return update;
+}
+
+function check ({ debug = false, debounce = TEN_MINUTES, timeout = 1000 }) {
+  return new Promise((resolve, reject) => {
+    const { _last_update_check } = cfg.read();
+    if (_last_update_check && _last_update_check + debounce > Date.now()) {
+      if (debug) {
+        const ago = ms(Date.now() - _last_update_check);
+        console.log(`> [debug] Skipping update. Last check ${ago} ago.`);
+      }
+      return;
+    }
+
+    if (debug) console.log(`> [debug] Checking for updates. Timeout in ${ms(timeout)}.`);
+
+    let timer;
+    let req = request.get('https://registry.npmjs.org/now', (res) => {
+      if (200 !== res.statusCode) {
+        if (debug) console.log(`> [debug] Update check error. NPM ${res.statusCode}.`);
+        resolve(false);
+        return;
+      }
+
+      res.resume();
+
+      const bufs = [];
+
+      res.on('data', (buf) => bufs.push(buf));
+
+      res.on('error', (err) => {
+        if (debug) console.log(`> [debug] Update check error: ${err.message}.`);
+        resolve(false);
+      });
+
+      res.on('end', () => {
+        clearTimeout(timer);
+        const buf = Buffer.concat(bufs);
+        let data;
+
+        try {
+          data = JSON.parse(buf.toString('utf8'));
+        } catch (err) {
+          if (debug) console.log(`> [debug] Update check JSON parse error: ${err.message}.`);
+          resolve(false);
+          return;
+        }
+
+        const { latest } = data['dist-tags'];
+        const current = pkg.version;
+
+        if (latest !== pkg.version) {
+          if (debug) console.log(`> [debug] Needs update. Current ${current}, latest ${latest}`);
+          resolve({
+            latest,
+            current,
+            at: new Date(data.time[latest])
+          });
+        } else {
+          if (debug) console.log(`> [debug] Up to date (${pkg.version}).`);
+          resolve(false);
+        }
+
+        cfg.merge({ _last_update_check: Date.now() });
+      });
+    })
+    .on('error', (err) => {
+      if (debug) console.log(`> [debug] Update check error: ${err.message}.`);
+      resolve(false);
+    });
+
+    timer = setTimeout(() => {
+      if (debug) console.log(`> [debug] Aborting update check after ${ms(timeout)}.`);
+      req.abort();
+      resolve(false);
+    }, timeout);
+  });
+}

lib/index.js

@@ -34,12 +34,16 @@ export default class Now extends EventEmitter {
       pkg = await readFile(resolve(path, 'package.json'));
       pkg = JSON.parse(pkg);
     } catch (err) {
-      throw new Error(`Failed to read JSON in "${path}/package.json"`);
+      const e = Error(`Failed to read JSON in "${path}/package.json"`);
+      e.userError = true;
+      throw e;
     }
 
     if (!pkg.scripts || !pkg.scripts.start) {
-      throw new Error('Missing `start` script in `package.json`. ' +
+      const e = Error('Missing `start` script in `package.json`. ' +
         'See: https://docs.npmjs.com/cli/start.');
+      e.userError = true;
+      throw e;
     }
 
     if (this._debug) console.time('> [debug] Getting files');