'at=error code=H10' WHILE DEPLOYING TO HEROKU

Question

So i have a project that i am trying to deploy to heroku and i keep getting the above error, let me share my code and if you need any other part of the code please ask, thank you It shows an application error when i open the app through heroku

first, the heroku logs --tail brings this result

    2021-01-11T13:11:58.739363+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/util.py", line 358, in import_app
2021-01-11T13:11:58.739364+00:00 app[web.1]: mod = importlib.import_module(module)
2021-01-11T13:11:58.739364+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/importlib/__init__.py", line 127, in import_module
2021-01-11T13:11:58.739365+00:00 app[web.1]: return _bootstrap._gcd_import(name[level:], package, level)
2021-01-11T13:11:58.739365+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
2021-01-11T13:11:58.739366+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 991, in _find_and_load
2021-01-11T13:11:58.739366+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
2021-01-11T13:11:58.739366+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
2021-01-11T13:11:58.739367+00:00 app[web.1]: File "<frozen importlib._bootstrap_external>", line 783, in exec_module
2021-01-11T13:11:58.739367+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
2021-01-11T13:11:58.739368+00:00 app[web.1]: File "/app/personalgallery/wsgi.py", line 16, in <module>
2021-01-11T13:11:58.739368+00:00 app[web.1]: application = get_wsgi_application()
2021-01-11T13:11:58.739368+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/core/wsgi.py", line 12, in get_wsgi_application
2021-01-11T13:11:58.739369+00:00 app[web.1]: django.setup(set_prefix=False)
2021-01-11T13:11:58.739369+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/__init__.py", line 19, in setup
2021-01-11T13:11:58.739369+00:00 app[web.1]: configure_logging(settings.LOGGING_CONFIG, settings.LOGGING)
2021-01-11T13:11:58.739370+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/conf/__init__.py", line 82, in __getattr__
2021-01-11T13:11:58.739370+00:00 app[web.1]: self._setup(name)
2021-01-11T13:11:58.739374+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/conf/__init__.py", line 69, in _setup
2021-01-11T13:11:58.739374+00:00 app[web.1]: self._wrapped = Settings(settings_module)
2021-01-11T13:11:58.739375+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/conf/__init__.py", line 170, in __init__
2021-01-11T13:11:58.739375+00:00 app[web.1]: mod = importlib.import_module(self.SETTINGS_MODULE)
2021-01-11T13:11:58.739375+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/importlib/__init__.py", line 127, in import_module
2021-01-11T13:11:58.739376+00:00 app[web.1]: return _bootstrap._gcd_import(name[level:], package, level)
2021-01-11T13:11:58.739376+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
2021-01-11T13:11:58.739377+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 991, in _find_and_load
2021-01-11T13:11:58.739377+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
2021-01-11T13:11:58.739377+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
2021-01-11T13:11:58.739378+00:00 app[web.1]: File "<frozen importlib._bootstrap_external>", line 783, in exec_module
2021-01-11T13:11:58.739378+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
2021-01-11T13:11:58.739378+00:00 app[web.1]: File "/app/personalgallery/settings.py", line 30, in <module>
2021-01-11T13:11:58.739379+00:00 app[web.1]: SECRET_KEY = config('SECRET_KEY')
2021-01-11T13:11:58.739379+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/decouple.py", line 199, in __call__
2021-01-11T13:11:58.739379+00:00 app[web.1]: return self.config(*args, **kwargs)
2021-01-11T13:11:58.739380+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/decouple.py", line 83, in __call__
2021-01-11T13:11:58.739380+00:00 app[web.1]: return self.get(*args, **kwargs)
2021-01-11T13:11:58.739380+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/decouple.py", line 68, in get
2021-01-11T13:11:58.739381+00:00 app[web.1]: raise UndefinedValueError('{} not found. Declare it as envvar or define a default value.'.format(option))
2021-01-11T13:11:58.739381+00:00 app[web.1]: decouple.UndefinedValueError: SECRET_KEY not found. Declare it as envvar or define a default value.
2021-01-11T13:11:58.739544+00:00 app[web.1]: [2021-01-11 13:11:58 +0000] [9] [INFO] Worker exiting (pid: 9)
2021-01-11T13:11:58.801056+00:00 app[web.1]: [2021-01-11 13:11:58 +0000] [10] [ERROR] Exception in worker process
2021-01-11T13:11:58.801058+00:00 app[web.1]: Traceback (most recent call last):
2021-01-11T13:11:58.801059+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/arbiter.py", line 583, in spawn_worker
2021-01-11T13:11:58.801060+00:00 app[web.1]: worker.init_process()
2021-01-11T13:11:58.801060+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/workers/base.py", line 119, in init_process
2021-01-11T13:11:58.801060+00:00 app[web.1]: self.load_wsgi()
2021-01-11T13:11:58.801061+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/workers/base.py", line 144, in load_wsgi
2021-01-11T13:11:58.801061+00:00 app[web.1]: self.wsgi = self.app.wsgi()
2021-01-11T13:11:58.801062+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/app/base.py", line 67, in wsgi
2021-01-11T13:11:58.801062+00:00 app[web.1]: self.callable = self.load()
2021-01-11T13:11:58.801063+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/app/wsgiapp.py", line 49, in load
2021-01-11T13:11:58.801063+00:00 app[web.1]: return self.load_wsgiapp()
2021-01-11T13:11:58.801064+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/app/wsgiapp.py", line 39, in load_wsgiapp
2021-01-11T13:11:58.801064+00:00 app[web.1]: return util.import_app(self.app_uri)
2021-01-11T13:11:58.801064+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/gunicorn/util.py", line 358, in import_app
2021-01-11T13:11:58.801065+00:00 app[web.1]: mod = importlib.import_module(module)
2021-01-11T13:11:58.801065+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/importlib/__init__.py", line 127, in import_module
2021-01-11T13:11:58.801066+00:00 app[web.1]: return _bootstrap._gcd_import(name[level:], package, level)
2021-01-11T13:11:58.801066+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
2021-01-11T13:11:58.801066+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 991, in _find_and_load
2021-01-11T13:11:58.801067+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
2021-01-11T13:11:58.801067+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
2021-01-11T13:11:58.801067+00:00 app[web.1]: File "<frozen importlib._bootstrap_external>", line 783, in exec_module
2021-01-11T13:11:58.801068+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
2021-01-11T13:11:58.801068+00:00 app[web.1]: File "/app/personalgallery/wsgi.py", line 16, in <module>
2021-01-11T13:11:58.801069+00:00 app[web.1]: application = get_wsgi_application()
2021-01-11T13:11:58.801069+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/core/wsgi.py", line 12, in get_wsgi_application
2021-01-11T13:11:58.801069+00:00 app[web.1]: django.setup(set_prefix=False)
2021-01-11T13:11:58.801070+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/__init__.py", line 19, in setup
2021-01-11T13:11:58.801070+00:00 app[web.1]: configure_logging(settings.LOGGING_CONFIG, settings.LOGGING)
2021-01-11T13:11:58.801070+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/conf/__init__.py", line 82, in __getattr__
2021-01-11T13:11:58.801071+00:00 app[web.1]: self._setup(name)
2021-01-11T13:11:58.801079+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/conf/__init__.py", line 69, in _setup
2021-01-11T13:11:58.801079+00:00 app[web.1]: self._wrapped = Settings(settings_module)
2021-01-11T13:11:58.801079+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/django/conf/__init__.py", line 170, in __init__
2021-01-11T13:11:58.801080+00:00 app[web.1]: mod = importlib.import_module(self.SETTINGS_MODULE)
2021-01-11T13:11:58.801080+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/importlib/__init__.py", line 127, in import_module
2021-01-11T13:11:58.801081+00:00 app[web.1]: return _bootstrap._gcd_import(name[level:], package, level)
2021-01-11T13:11:58.801081+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
2021-01-11T13:11:58.801081+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 991, in _find_and_load
2021-01-11T13:11:58.801082+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
2021-01-11T13:11:58.801082+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
2021-01-11T13:11:58.801082+00:00 app[web.1]: File "<frozen importlib._bootstrap_external>", line 783, in exec_module
2021-01-11T13:11:58.801083+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
2021-01-11T13:11:58.801083+00:00 app[web.1]: File "/app/personalgallery/settings.py", line 30, in <module>
2021-01-11T13:11:58.801083+00:00 app[web.1]: SECRET_KEY = config('SECRET_KEY')
2021-01-11T13:11:58.801084+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/decouple.py", line 199, in __call__
2021-01-11T13:11:58.801084+00:00 app[web.1]: return self.config(*args, **kwargs)
2021-01-11T13:11:58.801085+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/decouple.py", line 83, in __call__
2021-01-11T13:11:58.801085+00:00 app[web.1]: return self.get(*args, **kwargs)
2021-01-11T13:11:58.801085+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.8/site-packages/decouple.py", line 68, in get
2021-01-11T13:11:58.801086+00:00 app[web.1]: raise UndefinedValueError('{} not found. Declare it as envvar or define a default value.'.format(option))
2021-01-11T13:11:58.801086+00:00 app[web.1]: decouple.UndefinedValueError: SECRET_KEY not found. Declare it as envvar or define a default value.
2021-01-11T13:11:58.808950+00:00 app[web.1]: [2021-01-11 13:11:58 +0000] [10] [INFO] Worker exiting (pid: 10)
2021-01-11T13:11:59.029033+00:00 app[web.1]: [2021-01-11 13:11:59 +0000] [4] [INFO] Shutting down: Master
2021-01-11T13:11:59.029138+00:00 app[web.1]: [2021-01-11 13:11:59 +0000] [4] [INFO] Reason: Worker failed to boot.
2021-01-11T13:11:59.163235+00:00 heroku[web.1]: Process exited with status 3
2021-01-11T13:11:59.237160+00:00 heroku[web.1]: State changed from up to crashed
2021-01-11T13:12:12.047165+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=personalgalleryapp.herokuapp.com request_id=c8ed4df2-b33b-4644-afe8-fc482c8dc09e fwd="154.123.147.153" dyno= connect= service= status=503 bytes= protocol=https
2021-01-11T13:12:12.756886+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=personalgalleryapp.herokuapp.com request_id=be7fa125-4993-4b05-809e-75e8be4d3bbe fwd="154.123.147.153" dyno= connect= service= status=503 bytes= protocol=https

here is my procfile

web: gunicorn personalgallery.wsgi --log-file -

settings.py

 from pathlib import Path
import os
import django_heroku
import dj_database_url
from decouple import config,Csv


MODE=config("MODE", default="dev")
# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/3.1/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!

SECRET_KEY = config('SECRET_KEY')

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = config('DEBUG', default=False, cast=bool)

ALLOWED_HOSTS = ['*']


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'bootstrap3',
    'gallery.apps.GalleryConfig',
]

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

ROOT_URLCONF = 'personalgallery.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        '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',
            ],
        },
    },
]

WSGI_APPLICATION = 'personalgallery.wsgi.application'


# Database
# https://docs.djangoproject.com/en/3.1/ref/settings/#databases
if config('MODE')=="dev":

    DATABASES = {
        'default': {
            'ENGINE': 'django.db.backends.postgresql',
            'NAME': config('DB_NAME'),
            'USER': config('DB_USER'),
            'PASSWORD':config('DB_PASSWORD'),
            'HOST': config('DB_HOST'),
        }
    }

else:
    DATABASES = {
        'default': dj_database_url.config(
            default=config('DATABASE_URL')
        )
    }

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

ALLOWED_HOSTS = config('ALLOWED_HOSTS', cast=Csv())

# Password validation
# https://docs.djangoproject.com/en/3.1/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/3.1/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'Africa/Nairobi'

USE_I18N = True

USE_L10N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/3.1/howto/static-files/

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

STATICFILES_DIRS = [
    os.path.join(BASE_DIR, "static"),
]
STATICFILES_STORAGE = 'whitenoise.storage.CompressedManifestStaticFilesStorage'

MEDIA_URL = '/media/'
MEDIA_ROOT = os.path.join(BASE_DIR, 'media')

# Configure Django App for Heroku.
django_heroku.settings(locals())

Answer 1

In your log you have a line:

decouple.UndefinedValueError: SECRET_KEY not found. Declare it as envvar or define a default value.

This means your SECRET_KEY variable is not recognized, try changing it or make sure that the value is passsed correctly from your config file.