Detect Heroku deployment, remove psql requirement

This update sets up some settings to be adaptive based on whether
an app is deployed on Heroku, which is inferred from the environment
variable "ON_HEROKU" being set to "true".

This simplifies development setup a bit: Django's default SQLite
can be used to run locally.

.env.sample

@@ -1,4 +1,17 @@
-DATABASE_URL=postgres:///myurl
+################################
+#                              #
+#   THIS IS A SECRET FILE!!!   #
+#                              #
+# Do not add your .env to git! #
+#                              #
+################################
+
+# SECRET_KEY encrypts things. In production it should be a random string.
 SECRET_KEY=mysecretshouldnotbeongit
+
+# Set DATABASE_URL to use something other than the default SQLite.
+# DATABASE_URL=postgres:///myurl
+
+# Set Open Humans project CLIENT_ID and CLIENT_SECRET.
 OH_CLIENT_ID=myclientidshouldnotbeongit
 OH_CLIENT_SECRET=myclientsecretshouldnotbeongit

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2018 Bastian Greshake Tzovaras
+Copyright (c) 2018 Bastian Greshake Tzovaras, Mad Price Ball
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -24,17 +24,22 @@ conda create -n oh_uploader python=3.6
 pip install -r requirements.txt
 ```
 
-*Step 2: Install heroku-CLI & PostgreSQL*
+*Step 2: Install Heroku Command Line Interface (CLI)*
 
-If you are running MacOS the easiest way to do this is using [Homebrew](https://brew.sh/). If you are on a Linux machine you [should be able to do the same things using Linuxbrew](https://virtualenv.pypa.io/en/stable/). After installing Homebrew/Linuxbrew
-you can do:
+You should install the Heroku CLI to run this app. Heroku has [installation instructions for MacOS, Windows, and Linux](https://devcenter.heroku.com/articles/heroku-cli#download-and-install).
+
+If you are running MacOS the easiest way to do this is using [Homebrew](https://brew.sh/). After installing Homebrew you can do:
 
 ```
-brew install postgres
 brew install heroku/brew/heroku
 ```
 
-Once this is done you can start the setup of your *Open Humans uploader* by copying the example `.env` file (`cp .env.sample .env`) and entering at least your database URL. Once this is done you can migrate your database using `heroku local:run python manage.py migrate`. Afterwards you can start the webserver of your local heroku environment using `heroku local`.
+Once this is done you can complete minimal setup by:
+* Create an `.env` file from the example: `cp .env.sample .env`)
+* Edit `.env` to set a random string for `DJANGO_SECRET`
+* Migrate your database using `heroku local:run python manage.py migrate`
+
+Now you can run the webserver of your local heroku environment using `heroku local`.
 
 To fully set up your uploader you will have to modify some files, as described below.
 

config.yaml

@@ -7,8 +7,9 @@ project_description: This template demonstrates how you can run your own Open Hu
 # REQUIRED: Where can we find your project on Open Humans
 oh_activity_page: https://www.openhumans.org/activity/your-project-url/
 
-# REQUIRED: which URL will lead to your Open Humans uploader
-app_base_url: http://127.0.0.1:5000
+# Optional: which URL will lead to your Open Humans uploader
+# Defaults to http://127.0.0.1:500 if not set.
+# app_base_url: http://127.0.0.1:5000
 
 # REQUIRED: Tell Open Humans what kind of data is being uploaded
 file_description: This is an example file that doesnt have any meaning.

oh_data_uploader/settings.py

@@ -30,7 +30,13 @@
 # SECURITY WARNING: don't run with debug turned on in production!
 DEBUG = False if os.getenv('DEBUG', '').lower() == 'false' else True
 
-ALLOWED_HOSTS = ['*']
+# Establish whether this is running on Heroku
+ON_HEROKU = os.getenv('ON_HEROKU', '').lower() == 'true'
+
+if ON_HEROKU:
+    ALLOWED_HOSTS = ['*']
+else:
+    ALLOWED_HOSTS = []
 
 
 # Read OH settings from .env/environment variables
@@ -43,7 +49,8 @@
 YAML_CONFIG = yaml.load(''.join(yaml_content))
 YAML_CONFIG['file_tags_string'] = str(YAML_CONFIG['file_tags'])
 
-APP_BASE_URL = YAML_CONFIG['app_base_url']
+# Set up base URL.
+APP_BASE_URL = YAML_CONFIG.get('app_base_url', 'http://127.0.0.1:5000')
 if APP_BASE_URL[-1] == "/":
     APP_BASE_URL = APP_BASE_URL[:-1]
 
@@ -96,9 +103,16 @@
 # Database
 # https://docs.djangoproject.com/en/1.11/ref/settings/#databases
 
-db_from_env = dj_database_url.config(conn_max_age=500)
+DATABASES = {
+    'default': {
+        'ENGINE': 'django.db.backends.sqlite3',
+        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
+    }
+}
 
-DATABASES = {'default': db_from_env}
+if ON_HEROKU:
+    db_from_env = dj_database_url.config(conn_max_age=500)
+    DATABASES = {'default': db_from_env}
 
 
 # Password validation