Prevent repeating startup errors

dangerrangerous · Jul 16, 2014 · c39e153 · c39e153
1 parent 678edab
commit c39e153
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Showing 2 changed files with 48 additions and 9 deletions.
diff --git a/commands/start.js b/commands/start.js
@@ -1,5 +1,12 @@
 var shellify = require('shellify');
 var spawn = require('child_process').spawn;
+var Duplex = require('stream').Duplex;
+var util = require('util');
+var previousStart = new Date(0);
+
+// TODO: Make these thresholds configurable.
+var restartDelay = 500; // Try to restart in half a second
+var okTime = 2e3; // Call a restart "ok" if it goes 2 seconds without failing.
 
 module.exports = function (env) {
 
@@ -8,19 +15,51 @@ module.exports = function (env) {
    */
   function start() {
 
-    // Keep track of our start time.
-    var started = new Date();
+    var now = new Date();
+    var elapsed = now - previousStart;
+    previousStart = now;
+
+    // If it's been a while since we restarted, call this a clean start.
+    var isCleanStart = elapsed > okTime;
 
     // Spawn a child process and make it output to stdout.
     var child = spawn(process.execPath, ['app'], {env: {NODE_ENV: env}});
-    child.stderr.pipe(process.stdout);
-    child.stdout.pipe(process.stdout);
+
+    var pipeToStdout = function () {
+      child.stdout.pipe(process.stdout);
+      child.stderr.pipe(process.stdout);
+    };
+
+    // When starting cleanly, pipe child process output directly to stdout.
+    if (isCleanStart) {
+      pipeToStdout();
+    }
+
+    // After a fast failure, use a buffer in case we fail again.
+    else {
+      var isBuffering = true;
+      var data = '\n';
+
+      var append = function (chunk) {
+        data += chunk;
+      };
+
+      child.on('data', append);
+
+      // When we've started ok, write data to stdout and start piping.
+      var okTimer = setTimeout(function () {
+        process.stdout.write(data);
+        pipeToStdout();
+        child.removeListener('data', append);
+        data = null;
+      }, okTime);
+    }
 
     // Restart once a second at most.
     child.on('close', function () {
-      var elapsed = new Date() - started;
-      delay = Math.max(1e3 - elapsed, 0);
-      setTimeout(start, delay);
+      process.stdout.write('\u001b[31m.\u001b[39m');
+      clearTimeout(okTimer);
+      setTimeout(start, restartDelay);
     });
   }
 

diff --git a/lib/App.js b/lib/App.js
@@ -311,10 +311,10 @@ module.exports = Class.extend({
     var art = app.config.asciiArt || ['',
       red + bold + '     .A.     ' + grey + ("  _    _       _     _     " + normal + "v" + require('../package.json').version),
       red + bold + '    /@@@\\    ' + grey + " | |  (_) __ _| |__ | |_ ___ _ __",
-      red + '  ./@@' + yellow + 'A' + red + '@@\\.  ' + grey + " | |  | |/ _` | '_ \\| __/ _ \\ '__|",
+      red + '  ./@@' + yellow + 'A' + red + '@@\\.  ' + grey + " | |  | |/ _` | '_ \\| __/ _ \\ '__)",
       red + ' /@@' + yellow + '/@@@\\' + red + '@@\\ ' + grey + " | |__| | (_| | | | | ||  __/ |",
       red + '/@@' + yellow + '/@@' + white + 'A' + yellow + '@@\\' + red + '@@\\' + grey + " |____|_|\\__, |_| |_|\\__\\___|_|",
-      red + '#@@' + yellow + '#@' + white + '/@\\' + yellow + '@#' + red + '@@#' + grey + "          |___/",
+      red + '#@@' + yellow + '#@' + white + '/@\\' + yellow + '@#' + red + '@@#' + grey + "          (___/",
       red + '#@@' + yellow + '#@' + white + '@@@' + yellow + '@#' + red + '@@#  ',
       '"#@@' + yellow + '\\@@@/' + red + '@@#"  ' + normal,
       red + bold + ' \'"#######"\'   ' + normal,