部署Django+React到Heroku - 未捕获的语法错误。意外的标记'<'

Question

我正在尝试将我的Django+React应用部署到Heroku(Django只用于api，React用于前端)。这个视频，但几天都无法解决这个问题。

在部署过程中没有出现任何错误，但部署后，只出现白茫茫的屏幕。这是我到现在能找到的唯一线索......

我试着添加 type="text/babel" 到您的脚本标签，添加 base href 标签为index.html，并修改了几个 package.json 和 settings.py 选项。

这是我的 package.json 文件。

{
  "name": "frontend",
  "version": "0.1.0",
  "homepage": "https://myapp.herokuapp.com/",
  "private": true,
  "proxy": "http://localhost:8000",
  "dependencies": {
    "@material-ui/core": "^4.9.5",
    "@material-ui/icons": "^4.9.1",
    "@material-ui/lab": "^4.0.0-alpha.46",
    "@material-ui/styles": "^4.9.0",
    "@testing-library/jest-dom": "^4.2.4",
    "@testing-library/react": "^9.5.0",
    "@testing-library/user-event": "^7.2.1",
    "babel-preset-react": "^6.24.1",
    "react": "^16.13.0",
    "react-dom": "^16.13.0",
    "react-redux": "^5.0.7",
    "react-scripts": "3.2.0",
    "redux": "^4.0.0",
    "redux-thunk": "^2.3.0"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test",
    "eject": "react-scripts eject",
    "postinstall": "npm run build"
  },
  "engines": {
    "node": "12.14.0",
    "npm": "6.13.4"
  },
  "eslintConfig": {
    "extends": "react-app"
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  },
  "devDependencies": {
    "axios": "^0.19.2",
    "react-router-dom": "^5.1.2"
  }
}

而这是 settings.py 文件。

"""
Django settings for gradproj project.

Generated by 'django-admin startproject' using Django 2.0.13.

For more information on this file, see
https://docs.djangoproject.com/en/2.0/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/2.0/ref/settings/
"""

import os
import dj_database_url

# 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/2.0/howto/deployment/checklist/

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

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

ALLOWED_HOSTS = ['127.0.0.1', 'myapp.herokuapp.com']

# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',

    'corsheaders',
    'rest_framework',
    'rest_framework.authtoken',
    'django.contrib.sites',
    'allauth',
    'allauth.account',
    'allauth.socialaccount',
    'rest_auth',
    'rest_auth.registration',

    'whitenoise.runserver_nostatic',

    'community',
    'universities',
    'user',
]

SITE_ID = 1

MIDDLEWARE = [
    'whitenoise.middleware.WhiteNoiseMiddleware',
    'corsheaders.middleware.CorsMiddleware',
    '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',
]

ROOT_URLCONF = 'gradproj.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(BASE_DIR, 'build')],
        '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 = 'gradproj.wsgi.application'

# Database
# https://docs.djangoproject.com/en/2.0/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'myapp',
        'USER': 'user',
        'PASSWORD': '',
        'HOST': 'localhost',
        'PORT': '',
    }
}

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

# Password validation
# https://docs.djangoproject.com/en/2.0/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/2.0/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'Asia/Seoul'

USE_I18N = True

USE_L10N = True

USE_TZ = True

# Static files (CSS, javascript, Images)
# https://docs.djangoproject.com/en/2.0/howto/static-files/

STATIC_URL = '/static/'
STATICFILES_DIRS = [
    os.path.join(BASE_DIR, 'build/static'),
]

STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')
STATICFILES_STORAGE = 'whitenoise.storage.CompressedManifestStaticFilesStorage'

REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES': (
        'rest_framework.permissions.AllowAny',
    ),
    'DEFAULT_AUTHENTICATION_CLASSES': (
        'rest_framework.authentication.TokenAuthentication',
    ),
}

CORS_ORIGIN_ALLOW_ALL = True
# CORS_ORIGIN_WHITELIST = [
#     'http://localhost:3000',
# ]

CSRF_COOKIE_NAME = "csrftoken"

ACCOUNT_EMAIL_REQUIRED = False
ACCOUNT_AUTHENTICATION_METHOD = 'username'
ACCOUNT_EMAIL_VERIFICATION = 'none'

而这是 index.html 文件。

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <meta name="theme-color" content="#000000" />
    <meta
      name="description"
      content="Web site created using create-react-app"
    />
    <title>Project Title</title> 
  </head>
  <body>
    <noscript>You need to enable JavaScript to run this app.</noscript>
    <div id="root"></div>
  </body>
</html>

我没有接触任何关于webpack和babel的东西，因为我使用create-react-app来创建应用程序。对于数据库，我使用了mysql。我把Django和React文件夹都解压了，所以每个文件夹都在同一个目录下。这样.

我几乎读了每一个单一的帖子相关的这个问题在谷歌，现在我不知道我应该尝试什么。任何帮助将是非常感谢!