Enable Fastboot and run its Node server from Procfile

Author: kzys

Procfile

@@ -1,3 +1,3 @@
 release: bin/diesel migration run
-web: bin/start-nginx ./target/release/server
+web: node fastboot.js & bin/start-nginx target/release/server & wait -n
 background_worker: ./target/release/background-worker

config/environment.js

@@ -22,6 +22,10 @@ module.exports = function(environment) {
       // Here you can pass flags/options to your application instance
       // when it is created
     },
+
+    fastboot: {
+      hostWhitelist: ['crates.io', /^localhost:\d+$/, /\.herokuapp\.com$/],
+    },
   };
 
   if (environment === 'development') {

config/nginx.conf.erb

@@ -64,6 +64,11 @@ http {
 			proxy_pass http://app_server;
 		}
 
+		# Just in case, only forward "/policies" to Ember for a moment
+		location = /policies {
+			proxy_pass http://localhost:9000;
+		}
+
 		location ~ ^/api/v./crates/new$ {
 			proxy_pass http://app_server;
 

fastboot.js

@@ -0,0 +1,56 @@
+/* eslint-disable no-console */
+
+'use strict';
+
+const fs = require('fs');
+const FastBootAppServer = require('fastboot-app-server');
+
+// because fastboot-app-server uses cluster, but it might change in future
+const cluster = require('cluster');
+
+class LoggerWithoutTimestamp {
+    constructor() {
+        this.prefix = cluster.isMaster ? 'master' : 'worker';
+    }
+    writeLine() {
+        this._write('info', Array.prototype.slice.apply(arguments));
+    }
+
+    writeError() {
+        this._write('error', Array.prototype.slice.apply(arguments));
+    }
+
+    _write(level, args) {
+        args[0] = `[${level}][${this.prefix}] ${args[0]}`;
+        console.log.apply(console, args);
+    }
+}
+
+function writeAppInitializedWhenReady(logger) {
+    let timeout;
+
+    timeout = setInterval(function() {
+        logger.writeLine('waiting backend');
+        if (fs.existsSync('/tmp/backend-initialized')) {
+            logger.writeLine('backend is up. let heroku know the app is ready');
+            fs.writeFileSync('/tmp/app-initialized', 'hello');
+            clearInterval(timeout);
+        } else {
+            logger.writeLine('backend is still not up');
+        }
+    }, 1000);
+}
+
+var logger = new LoggerWithoutTimestamp();
+
+let server = new FastBootAppServer({
+    distPath: 'dist',
+    port: 9000,
+    ui: logger,
+});
+
+if (!cluster.isWorker) {
+    writeAppInitializedWhenReady(logger);
+}
+
+server.start();

src/bin/server.rs

@@ -102,8 +102,8 @@ fn main() {
     // Creating this file tells heroku to tell nginx that the application is ready
     // to receive traffic.
     if heroku {
-        println!("Writing to /tmp/app-initialized");
-        File::create("/tmp/app-initialized").unwrap();
+        println!("Writing to /tmp/backend-initialized");
+        File::create("/tmp/backend-initialized").unwrap();
     }
 
     // Block the main thread until the server has shutdown