500 error when Debug=False with Heroku and Django

Question

I am getting a funny 500 error when I switch to Debug=False in my Heroku app when I deploy. I have set Debug=True when I deploy just to try it out and it works perfectly - so the issue is only when Debug is set to False.

I'm not sure where to start here. Some searching has led me to believe it's whitenoise causing the issue but it's not clear. The command:

Output from heroku logs --source app

2018-09-13T12:29:53.137785+00:00 app[web.1]: 10.45.76.149 - - [13/Sep/2018:12:29:53 +0000] "GET / HTTP/1.1" 500 27 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0"
2018-09-13T12:29:53.279702+00:00 app[web.1]: 10.81.224.221 - - [13/Sep/2018:12:29:53 +0000] "GET /favicon.ico HTTP/1.1" 404 85 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0"
2018-09-13T12:29:53.792280+00:00 app[web.1]: 10.45.76.149 - - [13/Sep/2018:12:29:53 +0000] "GET /favicon.ico HTTP/1.1" 404 85 "-" "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0"

I have tried fixing as per this solution but to no avail;

See below for my settings:

import os
import posixpath
from os import environ

# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))



# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/1.9/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'A SECRET'

DEBUG = True

ALLOWED_HOSTS = ['*']




SITE_TITLE = "Penguiness"
SITE_TAGLINE = "Amazing records for amazing species"

# Application definition

INSTALLED_APPS = [
    'app',
    # Add your apps here to enable them
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'compressor',
    'gunicorn'
]

MIDDLEWARE_CLASSES = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
    'whitenoise.middleware.WhiteNoiseMiddleware',
]

ROOT_URLCONF = 'Penguinness.urls'


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.9/howto/static-files/


# STATICFILES_STORAGE = 'whitenoise.storage.CompressedManifestStaticFilesStorage'

STATIC_URL = '/static/'

STATIC_ROOT = posixpath.join(*(BASE_DIR.split(os.path.sep) + ['app/static']))

PROJECT_APP_PATH = os.path.dirname(os.path.abspath(__file__))
PROJECT_APP = os.path.basename(PROJECT_APP_PATH)
PROJECT_ROOT = BASE_DIR = os.path.dirname(PROJECT_APP_PATH)


TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(PROJECT_ROOT, "app/templates")], 
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
                'app.context_processors.global_settings',                
            ],
        },
    },
]

WSGI_APPLICATION = 'Penguinness.wsgi.application'


# Database
# https://docs.djangoproject.com/en/1.9/ref/settings/#databases

# DATABASES = {
#     'default': {
#         DATABASE STUFF
#     }
# }





SECURE_PROXY_SSL_HEADER = (
    "HTTP_X_FORWARDED_PROTO", 
    "https"
    )





# Password validation
# https://docs.djangoproject.com/en/1.9/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/1.9/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_L10N = True

USE_TZ = True


EMAIL_USE_TLS = True
EMAIL_BACKEND = 'django.core.mail.backends.smtp.EmailBackend'
EMAIL_HOST = 'smtp.gmail.com'
EMAIL_HOST_PASSWORD = PASSWORD #my gmail password
EMAIL_HOST_USER = EMAIL  #my gmail username
EMAIL_PORT = 587
DEFAULT_FROM_EMAIL = EMAIL_HOST_USER


import dj_database_url
db_from_env = dj_database_url.config(conn_max_age=500)
DATABASES['default'].update(db_from_env)

LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'formatters': {
        'verbose': {
            'format': ('%(asctime)s [%(process)d] [%(levelname)s] ' +
                       'pathname=%(pathname)s lineno=%(lineno)s ' +
                       'funcname=%(funcName)s %(message)s'),
            'datefmt': '%Y-%m-%d %H:%M:%S'
        },
        'simple': {
            'format': '%(levelname)s %(message)s'
        }
    },
    'handlers': {
        'null': {
            'level': 'DEBUG',
            'class': 'logging.NullHandler',
        },
        'console': {
            'level': 'DEBUG',
            'class': 'logging.StreamHandler',
            'formatter': 'verbose'
        }
    },
    'loggers': {
        'testlogger': {
            'handlers': ['console'],
            'level': 'INFO',
        }
    }
}

Answer 1

Okay - having battled for a bit I've found a solution to both issues I was having.

Issue 1: Unable to view heroku logs --source app:

I had to first add LOGGING to the settings.py file:

LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'formatters': {
        'verbose': {
            'format': ('%(asctime)s [%(process)d] [%(levelname)s] ' +
                       'pathname=%(pathname)s lineno=%(lineno)s ' +
                       'funcname=%(funcName)s %(message)s'),
            'datefmt': '%Y-%m-%d %H:%M:%S'
        },
        'simple': {
            'format': '%(levelname)s %(message)s'
        }
    },
    'handlers': {
        'null': {
            'level': 'DEBUG',
            'class': 'logging.NullHandler',
        },
        'console': {
            'level': 'DEBUG',
            'class': 'logging.StreamHandler',
            'formatter': 'verbose'
        }
    },
    'loggers': {
        'testlogger': {
            'handlers': ['console'],
            'level': 'INFO',
        }
    }
}

More importantly was to get the relevant errors to propagate up through the Heroku logs. To do this, in settings.py I wrote the line:

DEBUG_PROPAGATE_EXCEPTIONS = True

This gave me an error associated with my static files. More specifically, it was giving me this error:

ValueError: Missing staticfiles manifest entry for 'images/favicon.png'

Issue 2: the 500 error

After determining that there was an error processing static images, I searched and someone suggested running:

python manage.py collectstatic

I did this, but was still finding the error. The next thing was to ensure that Whitenoise was commented out:

#STATICFILES_STORAGE = 'whitenoise.storage.CompressedManifestStaticFilesStorage'

However, this was resulting in the error:

2018-09-13T13:13:49.905187+00:00 app[web.1]: "When using Django Compressor together with staticfiles, "
2018-09-13T13:13:49.905190+00:00 app[web.1]: ImproperlyConfigured: When using Django Compressor together with staticfiles, please add 'compressor.finders.CompressorFinder' to the STATICFILES_FINDERS setting.

I tried to add compressor.finders.CompressorFinder but that gave me a similar error to above. So I ignored that. After some searching I found that I had to basically disable compressor (at least as I understand it) by adding this to settings.py:

COMPRESS_ENABLED = os.environ.get('COMPRESS_ENABLED', False)

This didn't completely fix the problem as then I was having issues locating the static files. So, I had to set my STATIC_ROOT to this:

STATIC_ROOT = os.path.join(BASE_DIR, 'static')

Pushed to heroku and there you have it... Debug=False now working

Answer 2

STATICFILES_STORAGE = 'django.contrib.staticfiles.storage.StaticFilesStorage'

helped in my case