make the digitalocean module wait for the SSH port to become alive before resolving

Author: trevj

src/cloud/digitalocean/freedom-module.json

@@ -67,6 +67,7 @@
   "permissions": [
     "core.xhr",
     "core.oauth",
-    "core.storage"
+    "core.storage",
+    "core.tcpsocket"
   ]
 }

src/cloud/digitalocean/provisioner.ts

@@ -1,5 +1,7 @@
 /// <reference path='../../../../third_party/typings/browser.d.ts' />
 
+import promises = require('../../promises/promises');
+
 declare const freedom: freedom.FreedomInModuleEnv;
 
 // TODO: https://github.com/uProxy/uproxy/issues/2051
@@ -107,8 +109,32 @@ class Provisioner {
           break;
         }
       }
-      console.log(this.state_);
-      return this.state_;
+
+      // Spin until the server is truly up.
+      // Give it one minute before declaring bankruptcy.
+      console.log('waiting for activity on port 22');
+      return promises.retry(() => {
+        const socket = freedom['core.tcpsocket']();
+
+        const destructor = () => {
+          try {
+            freedom['core.tcpsocket'].close(socket);
+          } catch (e) {
+            console.warn('error destroying socket: ' + e.message);
+          }
+        };
+
+        // TODO: Worth thinking about timeouts here but because this times
+        //       out almost immediately if nothing is listening on the port,
+        //       it works well for our purposes.
+        return socket.connect(this.state_.network['ipv4'], 22).then((unused: any) => {
+          destructor();
+          return this.state_;
+        }, (e: Error) => {
+          destructor();
+          throw e;
+        });
+      }, 60, 1000);
     });
   }