Merge pull request #433 from NYUCCL/heroku_instructions

Heroku instructions warn about exposing database_url.

doc/heroku.rst

@@ -47,22 +47,6 @@ If you're starting from a preexisting psiturk app, you need to grab three files
 
     heroku addons:create heroku-postgresql
 
-#. Get the URL of the Postgres database that you just created: ::
-
-    heroku config:get DATABASE_URL
-
-#. Get the URL of your app: ::
-
-    heroku domains
-
-#. In your psiTurk example, open the `config.txt` file. Here, find and make the following settings for the these rows, and then save the file: ::
-
-    database_url = <Your Postgres database URL that you retrieved above>
-    host = 0.0.0.0
-    threads = 1
-    ad_location = https://<Your app URL that you retrieved above>/pub
-    use_psiturk_ad_server = false    
-
 #. Run the following commands, replacing `<XYZ>` with your access and secret keys for `Amazon Web Services <amt_setup.html#obtaining-aws-credentials>`_ and `psiTurk Secure Ad Server <psiturk_org_setup.html#obtaining-psiturk-org-api-credentials>`_ (you can also use `this Python script <https://github.com/NYUCCL/psiTurk/blob/908ce7bcfc8fb6b38d94dbae480449324c5d9d51/psiturk/example/set-heroku-settings.py>`_ to automatically run these commmands, provided that you've filled out your credentials in your `.psiturkconfig` file. Running this script is the recommended approach!): ::
 
     heroku config:set ON_CLOUD=true
@@ -71,6 +55,10 @@ If you're starting from a preexisting psiturk app, you need to grab three files
     heroku config:set aws_access_key_id=<XYZ>
     heroku config:set aws_secret_access_key=<XYZ>
 
+   You don't need all of these settings if you run psiTurk standalone, independent of Amazon Mechanical Turk.
+   However, you still need specify `ON_CLOUD=true` or psiTurk will not bind to the port specified by Heroku.
+   In that case the app log on Heroku will say `Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch`.
+
 #. Stage all the files in your psiTurk example to your Git repository: ::
 
     git add .
@@ -83,6 +71,27 @@ If you're starting from a preexisting psiturk app, you need to grab three files
 
     git push heroku master
 
+#. Get the URL of the Postgres database that you just created: ::
+
+    heroku config:get DATABASE_URL
+
+#. Get the URL of your app: ::
+
+    heroku domains
+
+#. In your psiTurk example, open the `config.txt` file. Here, find and make the following settings for the these rows, and then save the file: ::
+
+    database_url = <Your Postgres database URL that you retrieved above>
+    host = 0.0.0.0
+    threads = 1
+    ad_location = https://<Your app URL that you retrieved above>/pub
+    use_psiturk_ad_server = false
+
+   Your local psiTurk instance needs these settings to communicate with the database on Heroku.
+   You do not need to push these settings to Heroku to make them work.
+   Specifically, be careful who has access to this file and do not push this information to any public git repositories:
+   **anyone who has access to the database_url can connect to your database and has access to the data stored in it!**
+
 #. Run `psiTurk` locally on your machine: ::
 
     psiturk