Heroku上Django应用DEBUG=False时500错误及图片丢失问题求助

• 将DEBUG设置为False时，访问登录或注册页面出现500服务器错误；设为True时，登录和注册页面可正常打开。
• 上传的图片仅能显示一段时间，再次访问页面时图片会消失。

"""
Django settings for EtufuorFarm project.

Generated by 'django-admin startproject' using Django 4.1.6.

For more information on this file, see
https://docs.djangoproject.com/en/4.1/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/4.1/ref/settings/
"""

import datetime
import os
from pathlib import Path
import dj_database_url
import django_heroku

# 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/4.1/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = os.environ.get('SECRET_KEY', 'django-insecure-qut(+bhgj@au6z4tl!_z8c(k%yes@)f(8x4lb%l6knh7n$d')

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = ['etufuormarket.herokuapp.com']


# Application definition

INSTALLED_APPS = [
    #'admin_material.apps.AdminMaterialDashboardConfig',
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'farmapp.apps.FarmappConfig',
    'crispy_forms',
    'django_filters',
    'crispy_bootstrap5',
    #'social_django',
    'rest_framework',
    'corsheaders',
   # 'rest_framework_jwt',
]
CRISPY_ALLOWED_TEMPLATE_PACKS = "bootstrap5"

CRISPY_TEMPLATE_PACK = "bootstrap5"

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',
    # Third Part Middleware
    'whitenoise.middleware.WhiteNoiseMiddleware',
    'corsheaders.middleware.CorsMiddleware',
    'django.middleware.common.CommonMiddleware',
    
]

ROOT_URLCONF = 'EtufuorFarm.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',
                'social_django.context_processors.backends',
                'social_django.context_processors.login_redirect',
            ],
        },
    },
]

WSGI_APPLICATION = 'EtufuorFarm.wsgi.application'
AUTHENTICATION_BACKENDS = [
    'social_core.backends.google.GoogleOAuth2',
    'django.contrib.auth.backends.ModelBackend',
]

# Database
# https://docs.djangoproject.com/en/4.1/ref/settings/#databases

# DATABASES = {
#     'default': {
#         'ENGINE': 'django.db.backends.sqlite3',
#         'NAME': BASE_DIR / 'db.sqlite3',
#     }
# }
DATABASES = {
    'default': dj_database_url.config(conn_max_age=600, ssl_require=True)
}

# Password validation
# https://docs.djangoproject.com/en/4.1/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',
    },
]

REST_FRAMEWORK = {
    'DEFAULT_RENDERER_CLASSES': [
        'rest_framework.renderers.JSONRenderer',
        'rest_framework.renderers.BrowsableAPIRenderer',
    ],
    'DEFAULT_PARSER_CLASSES': (
        'rest_framework.parsers.JSONParser',
        'rest_framework.parsers.FormParser',
        'rest_framework.parsers.MultiPartParser',
    ),
}

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_TZ = True


DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'
STATIC_URL = '/static/'

MEDIA_URL = '/media/'

STATIC_ROOT = os.path.join(BASE_DIR, 'static')
MEDIA_ROOT = os.path.join(BASE_DIR, 'media')
STATICFILES_DIRS = (os.path.join(BASE_DIR, 'static'),)
AUTH_USER_MODEL = 'farmapp.CustomUser'

TIME_ZONE = 'Africa/Accra'


LOGIN_URL = '/login'

#LOGIN_REDIRECT_URL = '/'
LOGOUT_REDIRECT_URL = '/'
STATICFILES_STORAGE = 'whitenoise.storage.CompressedManifestStaticFilesStorage'


django_heroku.settings(locals())

1. DEBUG=False时500错误修复 #

核心原因 #

• 模板上下文处理器引用了social_django相关模块，但INSTALLED_APPS中该应用被注释，导致模板渲染失败；
• DEBUG关闭后，Django不自动处理静态文件，且隐藏错误详情，无法直接定位问题。

修复步骤 #

• 启用缺失的应用：取消INSTALLED_APPS中'social_django'的注释，因为模板上下文处理器依赖该应用：

  INSTALLED_APPS = [
      # ... 其他已有应用
      'social_django',
      # ... 其他已有应用
  ]
  

• 确保静态文件正常加载：部署前执行python manage.py collectstatic，将静态文件收集到STATIC_ROOT目录，Whitenoise会自动处理这些文件的分发；
• 配置日志排查隐藏错误：如果仍有500错误，添加日志配置查看详细报错信息：

  LOGGING = {
      'version': 1,
      'disable_existing_loggers': False,
      'handlers': {
          'console': {'class': 'logging.StreamHandler'},
      },
      'root': {
          'handlers': ['console'],
          'level': 'ERROR',
      },
  }
  

  运行heroku logs --tail查看Heroku日志，即可获取500错误的具体堆栈信息。

2. 上传图片消失问题修复 #

核心原因 #

Heroku使用临时文件系统，所有上传到服务器本地的文件会在应用重启（代码部署、dyno休眠唤醒等场景）后被清空，导致图片无法持久化存储。

修复步骤 #

使用第三方云存储服务存储媒体文件，以AWS S3为例：

1. 安装依赖包：pip install django-storages boto3
2. 在settings.py中添加云存储配置：

   INSTALLED_APPS += ['storages']
   
   AWS_ACCESS_KEY_ID = os.environ.get('AWS_ACCESS_KEY_ID')
   AWS_SECRET_ACCESS_KEY = os.environ.get('AWS_SECRET_ACCESS_KEY')
   AWS_STORAGE_BUCKET_NAME = os.environ.get('AWS_STORAGE_BUCKET_NAME')
   AWS_S3_REGION_NAME = os.environ.get('AWS_S3_REGION_NAME')
   AWS_S3_FILE_OVERWRITE = False
   AWS_DEFAULT_ACL = 'public-read'
   AWS_S3_CUSTOM_DOMAIN = f'{AWS_STORAGE_BUCKET_NAME}.s3.amazonaws.com'
   
   # 将媒体文件存储到S3
   DEFAULT_FILE_STORAGE = 'storages.backends.s3boto3.S3Boto3Storage'
   MEDIA_URL = f'https://{AWS_S3_CUSTOM_DOMAIN}/media/'
   

3. 在Heroku的环境变量中配置AWS密钥、存储桶名等信息，避免硬编码敏感数据。

内容的提问来源于stack exchange，提问作者Justice Morison