text: # Django settings for zulip project.
  ########################################################################
  # Here's how settings for the Zulip project work:
  #
  # * settings.py contains non-site-specific and settings configuration
  # for the Zulip Django app.
  # * settings.py imports prod_settings.py, and any site-specific configuration
  # belongs there.  The template for prod_settings.py is prod_settings_template.py
  #
  # See https://zulip.readthedocs.io/en/latest/subsystems/settings.html for more information
  #
  ########################################################################
  from copy import deepcopy
  import os
  import time
  import sys
  from typing import Any, Dict, List, Union
  
  from zerver.lib.db import TimeTrackingConnection
  import zerver.lib.logging_util
  
  ########################################################################
  # INITIAL SETTINGS
  ########################################################################
  
  from .config import DEPLOY_ROOT, PRODUCTION, DEVELOPMENT, get_secret, get_config, get_from_file_if_exists
  
  # Make this unique, and don't share it with anybody.
  SECRET_KEY = get_secret("secret_key")
  
  # A shared secret, used to authenticate different parts of the app to each other.
  SHARED_SECRET = get_secret("shared_secret")
  
  # We use this salt to hash a user's email into a filename for their user-uploaded
  # avatar.  If this salt is discovered, attackers will only be able to determine
  # that the owner of an email account has uploaded an avatar to Zulip, which isn't
  # the end of the world.  Don't use the salt where there is more security exposure.
  AVATAR_SALT = get_secret("avatar_salt")
  
  # SERVER_GENERATION is used to track whether the server has been
  # restarted for triggering browser clients to reload.
  SERVER_GENERATION = int(time.time())
  
  # Key to authenticate this server to zulip.org for push notifications, etc.
  ZULIP_ORG_KEY = get_secret("zulip_org_key")
  ZULIP_ORG_ID = get_secret("zulip_org_id")
  
  if 'DEBUG' not in globals():
      # Uncomment end of next line to test CSS minification.
      # For webpack JS minification use tools/run_dev.py --minify
      DEBUG = DEVELOPMENT  # and platform.node() != 'your-machine'
  
  if DEBUG:
      INTERNAL_IPS = ('127.0.0.1',)
  
  # Detect whether we're running as a queue worker; this impacts the logging configuration.
  if len(sys.argv) > 2 and sys.argv[0].endswith('manage.py') and sys.argv[1] == 'process_queue':
      IS_WORKER = True
  else:
      IS_WORKER = False
  
  
  # This is overridden in test_settings.py for the test suites
  TEST_SUITE = False
  # The new user tutorial is enabled by default, but disabled for client tests.
  TUTORIAL_ENABLED = True
  # This is overridden in test_settings.py for the test suites
  CASPER_TESTS = False
  # This is overridden in test_settings.py for the test suites
  RUNNING_OPENAPI_CURL_TEST = False
  # This is overridden in test_settings.py for the test suites
  GENERATE_STRIPE_FIXTURES = False
  
  # Google Compute Engine has an /etc/boto.cfg that is "nicely
  # configured" to work with GCE's storage service.  However, their
  # configuration is super aggressive broken, in that it means importing
  # boto in a virtualenv that doesn't contain the GCE tools crashes.
  #
  # By using our own path for BOTO_CONFIG, we can cause boto to not
  # process /etc/boto.cfg.
  os.environ['BOTO_CONFIG'] = '/etc/zulip/boto.cfg'
  
  ########################################################################
  # DEFAULT VALUES FOR SETTINGS
  ########################################################################
  
  # For any settings that are not set in the site-specific configuration file
  # (/etc/zulip/settings.py in production, or dev_settings.py or test_settings.py
  # in dev and test), we want to initialize them to sane defaults.
  from .default_settings import *
  
  # Import variables like secrets from the prod_settings file
  # Import prod_settings after determining the deployment/machine type
  if PRODUCTION:
      from .prod_settings import *
  else:
      from .dev_settings import *
  
  # These are the settings that we will check that the user has filled in for
  # production deployments before starting the app.  It consists of a series
  # of pairs of (setting name, default value that it must be changed from)
  REQUIRED_SETTINGS = [("EXTERNAL_HOST", "zulip.example.com"),
                       ("ZULIP_ADMINISTRATOR", "zulip-admin@example.com"),
                       # SECRET_KEY doesn't really need to be here, in
                       # that we set it automatically, but just in
                       # case, it seems worth having in this list
                       ("SECRET_KEY", ""),
                       ("AUTHENTICATION_BACKENDS", ()),
                       ]
  
  MANAGERS = ADMINS
  
  ########################################################################
  # STANDARD DJANGO SETTINGS
  ########################################################################
  
  # Local time zone for this installation. Choices can be found here:
  # http://en.wikipedia.org/wiki/List_of_tz_zones_by_name
  # although not all choices may be available on all operating systems.
  # In a Windows environment this must be set to your system time zone.
  TIME_ZONE = 'UTC'
  
  # Language code for this installation. All choices can be found here:
  # http://www.i18nguy.com/unicode/language-identifiers.html
  LANGUAGE_CODE = 'en-us'
  
  # If you set this to False, Django will make some optimizations so as not
  # to load the internationalization machinery.
  USE_I18N = True
  
  # If you set this to False, Django will not format dates, numbers and
  # calendars according to the current locale.
  USE_L10N = True
  
  # If you set this to False, Django will not use timezone-aware datetimes.
  USE_TZ = True
  
  # this directory will be used to store logs for development environment
  DEVELOPMENT_LOG_DIRECTORY = os.path.join(DEPLOY_ROOT, 'var', 'log')
  # Make redirects work properly behind a reverse proxy
  USE_X_FORWARDED_HOST = True
  
  # Extend ALLOWED_HOSTS with localhost (needed to RPC to Tornado),
  ALLOWED_HOSTS += ['127.0.0.1', 'localhost']
  # ... with hosts corresponding to EXTERNAL_HOST,
  ALLOWED_HOSTS += [EXTERNAL_HOST.split(":")[0],
                    '.' + EXTERNAL_HOST.split(":")[0]]
  # ... and with the hosts in REALM_HOSTS.
  ALLOWED_HOSTS += REALM_HOSTS.values()
  
  from django.template.loaders import app_directories
  class TwoFactorLoader(app_directories.Loader):
      def get_dirs(self) -> List[str]:
          dirs = super().get_dirs()
          return [d for d in dirs if 'two_factor' in d]
  
  MIDDLEWARE = (
      # With the exception of it's dependencies,
      # our logging middleware should be the top middleware item.
      'zerver.middleware.TagRequests',
      'zerver.middleware.SetRemoteAddrFromForwardedFor',
      'zerver.middleware.LogRequests',
      'zerver.middleware.JsonErrorHandler',
      'zerver.middleware.RateLimitMiddleware',
      'zerver.middleware.FlushDisplayRecipientCache',
      'zerver.middleware.ZulipCommonMiddleware',
      'zerver.middleware.SessionHostDomainMiddleware',
      'django.middleware.locale.LocaleMiddleware',
      'django.middleware.csrf.CsrfViewMiddleware',
      'django.contrib.auth.middleware.AuthenticationMiddleware',
      # Make sure 2FA middlewares come after authentication middleware.
      'django_otp.middleware.OTPMiddleware',  # Required by Two Factor auth.
      'two_factor.middleware.threadlocals.ThreadLocals',  # Required by Twilio
      # Needs to be after CommonMiddleware, which sets Content-Length
      'zerver.middleware.FinalizeOpenGraphDescription',
      # django oauth toolkit
      'corsheaders.middleware.CorsMiddleware',
  )
  
  ANONYMOUS_USER_ID = None
  
  AUTH_USER_MODEL = "zerver.UserProfile"
  
  TEST_RUNNER = 'zerver.lib.test_runner.Runner'
  
  ROOT_URLCONF = 'zproject.urls'
  
  # Python dotted path to the WSGI application used by Django's runserver.
  WSGI_APPLICATION = 'zproject.wsgi.application'
  
  # A site can include additional installed apps via the
  # EXTRA_INSTALLED_APPS setting
  INSTALLED_APPS = [
      'django.contrib.auth',
      'django.contrib.contenttypes',
      'django.contrib.sessions',
      'django.contrib.staticfiles',
      'confirmation',
      'webpack_loader',
      'zerver',
      'social_django',
      # 2FA related apps.
      'django_otp',
      'django_otp.plugins.otp_static',
      'django_otp.plugins.otp_totp',
      'two_factor',
      # oatuh toolkit
      'oauth2_provider',
  ]
  if USING_PGROONGA:
      INSTALLED_APPS += ['pgroonga']
  INSTALLED_APPS += EXTRA_INSTALLED_APPS
  
  ZILENCER_ENABLED = 'zilencer' in INSTALLED_APPS
  CORPORATE_ENABLED = 'corporate' in INSTALLED_APPS
  
  # Base URL of the Tornado server
  # We set it to None when running backend tests or populate_db.
  # We override the port number when running frontend tests.
  TORNADO_PROCESSES = int(get_config('application_server', 'tornado_processes', '1'))
  TORNADO_SERVER = 'http://127.0.0.1:9993'  # type: Optional[str]
  RUNNING_INSIDE_TORNADO = False
  AUTORELOAD = DEBUG
  
  SILENCED_SYSTEM_CHECKS = [
      # auth.W004 checks that the UserProfile field named by USERNAME_FIELD has
      # `unique=True`.  For us this is `email`, and it's unique only per-realm.
      # Per Django docs, this is perfectly fine so long as our authentication
      # backends support the username not being unique; and they do.
      # See: https://docs.djangoproject.com/en/2.2/topics/auth/customizing/#django.contrib.auth.models.CustomUser.USERNAME_FIELD
      "auth.W004",
  ]
  
  ########################################################################
  # DATABASE CONFIGURATION
  ########################################################################
  
  # Zulip's Django configuration supports 4 different ways to do
  # postgres authentication:
  #
  # * The development environment uses the `local_database_password`
  #   secret from `zulip-secrets.conf` to authenticate with a local
  #   database.  The password is automatically generated and managed by
  #   `generate_secrets.py` during or provision.
  #
  # The remaining 3 options are for production use:
  #
  # * Using postgres' "peer" authentication to authenticate to a
  #   database on the local system using one's user ID (processes
  #   running as user `zulip` on the system are automatically
  #   authenticated as database user `zulip`).  This is the default in
  #   production.  We don't use this in the development environment,
  #   because it requires the developer's user to be called `zulip`.
  #
  # * Using password authentication with a remote postgres server using
  #   the `REMOTE_POSTGRES_HOST` setting and the password from the
  #   `postgres_password` secret.
  #
  # * Using passwordless authentication with a remote postgres server
  #   using the `REMOTE_POSTGRES_HOST` setting and a client certificate
  #   under `/home/zulip/.postgresql/`.
  #
  # We implement these options with a default DATABASES configuration
  # supporting peer authentication, with logic to override it as
  # appropriate if DEVELOPMENT or REMOTE_POSTGRES_HOST is set.
  DATABASES = {"default": {
      'ENGINE': 'django.db.backends.postgresql',
      'NAME': 'zulip',
      'USER': 'zulip',
      # Password = '' => peer/certificate authentication (no password)
      'PASSWORD': '',
      # Host = '' => connect to localhost by default
      'HOST': '',
      'SCHEMA': 'zulip',
      'CONN_MAX_AGE': 600,
      'OPTIONS': {
          'connection_factory': TimeTrackingConnection
      },
  }}  # type: Dict[str, Dict[str, Any]]
  
  if DEVELOPMENT:
      LOCAL_DATABASE_PASSWORD = get_secret("local_database_password")
      DATABASES["default"].update({
          'PASSWORD': LOCAL_DATABASE_PASSWORD,
          'HOST': 'localhost'
      })
  elif REMOTE_POSTGRES_HOST != '':
      DATABASES['default'].update({
          'HOST': REMOTE_POSTGRES_HOST,
          'PORT': REMOTE_POSTGRES_PORT
      })
      if get_secret("postgres_password") is not None:
          DATABASES['default'].update({
              'PASSWORD': get_secret("postgres_password"),
          })
      if REMOTE_POSTGRES_SSLMODE != '':
          DATABASES['default']['OPTIONS']['sslmode'] = REMOTE_POSTGRES_SSLMODE
      else:
          DATABASES['default']['OPTIONS']['sslmode'] = 'verify-full'
  
  POSTGRES_MISSING_DICTIONARIES = bool(get_config('postgresql', 'missing_dictionaries', None))
  
  ########################################################################
  # RABBITMQ CONFIGURATION
  ########################################################################
  
  USING_RABBITMQ = True
  RABBITMQ_PASSWORD = get_secret("rabbitmq_password")
  
  ########################################################################
  # CACHING CONFIGURATION
  ########################################################################
  
  SESSION_ENGINE = "django.contrib.sessions.backends.cached_db"
  
  # Compress large values being stored in memcached; this is important
  # for at least the realm_users cache.
  PYLIBMC_MIN_COMPRESS_LEN = 100 * 1024
  PYLIBMC_COMPRESS_LEVEL = 1
  
  MEMCACHED_PASSWORD = get_secret("memcached_password")
  
  CACHES = {
      'default': {
          'BACKEND': 'django_pylibmc.memcached.PyLibMCCache',
          'LOCATION': MEMCACHED_LOCATION,
          'TIMEOUT': 3600,
          'BINARY': True,
          'USERNAME': MEMCACHED_USERNAME,
          'PASSWORD': MEMCACHED_PASSWORD,
          'OPTIONS': {
              'tcp_nodelay': True,
              'retry_timeout': 1,
          }
      },
      'database': {
          'BACKEND': 'django.core.cache.backends.db.DatabaseCache',
          'LOCATION': 'third_party_api_results',
          # This cache shouldn't timeout; we're really just using the
          # cache API to store the results of requests to third-party
          # APIs like the Twitter API permanently.
          'TIMEOUT': None,
          'OPTIONS': {
              'MAX_ENTRIES': 100000000,
              'CULL_FREQUENCY': 10,
          }
      },
      'in-memory': {
          'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
      },
  }
  
  ########################################################################
  # REDIS-BASED RATE LIMITING CONFIGURATION
  ########################################################################
  
  RATE_LIMITING_RULES = {
      'api_by_user': [
          (60, 200),  # 200 requests max every minute
      ],
      'authenticate_by_username': [
          (1800, 5),  # 5 login attempts within 30 minutes
      ],
      'password_reset_form_by_email': [
          (3600, 2),  # 2 reset emails per hour
          (86400, 5),  # 5 per day
      ],
  }
  
  RATE_LIMITING_MIRROR_REALM_RULES = [
      (60, 50),  # 50 emails per minute
      (300, 120),  # 120 emails per 5 minutes
      (3600, 600),  # 600 emails per hour
  ]
  
  DEBUG_RATE_LIMITING = DEBUG
  REDIS_PASSWORD = get_secret('redis_password')
  
  ########################################################################
  # SECURITY SETTINGS
  ########################################################################
  
  SESSION_COOKIE_SAMESITE = 'Lax'
  
  # Tell the browser to never send our cookies without encryption, e.g.
  # when executing the initial http -> https redirect.
  #
  # Turn it off for local testing because we don't have SSL.
  if PRODUCTION:
      SESSION_COOKIE_SECURE = True
      CSRF_COOKIE_SECURE = True
  
      # For get_updates hostname sharding.
      domain = get_config('django', 'cookie_domain', None)
      if domain is not None:
          CSRF_COOKIE_DOMAIN = '.' + domain
  
  # Prevent Javascript from reading the CSRF token from cookies.  Our code gets
  # the token from the DOM, which means malicious code could too.  But hiding the
  # cookie will slow down some attackers.
  CSRF_COOKIE_PATH = '/;HttpOnly'
  CSRF_FAILURE_VIEW = 'zerver.middleware.csrf_failure'
  
  if DEVELOPMENT:
      # Use fast password hashing for creating testing users when not
      # PRODUCTION.  Saves a bunch of time.
      PASSWORD_HASHERS = (
          'django.contrib.auth.hashers.SHA1PasswordHasher',
          'django.contrib.auth.hashers.PBKDF2PasswordHasher'
      )
      # Also we auto-generate passwords for the default users which you
      # can query using ./manage.py print_initial_password
      INITIAL_PASSWORD_SALT = get_secret("initial_password_salt")
  else:
      # For production, use the best password hashing algorithm: Argon2
      # Zulip was originally on PBKDF2 so we need it for compatibility
      PASSWORD_HASHERS = ('django.contrib.auth.hashers.Argon2PasswordHasher',
                          'django.contrib.auth.hashers.PBKDF2PasswordHasher')
  
  ########################################################################
  # API/BOT SETTINGS
  ########################################################################
  
  ROOT_DOMAIN_URI = EXTERNAL_URI_SCHEME + EXTERNAL_HOST
  
  if "NAGIOS_BOT_HOST" not in vars():
      NAGIOS_BOT_HOST = EXTERNAL_HOST
  
  S3_KEY = get_secret("s3_key")
  S3_SECRET_KEY = get_secret("s3_secret_key")
  
  if LOCAL_UPLOADS_DIR is not None:
      if SENDFILE_BACKEND is None:
          SENDFILE_BACKEND = 'django_sendfile.backends.nginx'
      SENDFILE_ROOT = os.path.join(LOCAL_UPLOADS_DIR, "files")
      SENDFILE_URL = '/serve_uploads'
  
  # GCM tokens are IP-whitelisted; if we deploy to additional
  # servers you will need to explicitly add their IPs here:
  # https://cloud.google.com/console/project/apps~zulip-android/apiui/credential
  ANDROID_GCM_API_KEY = get_secret("android_gcm_api_key")
  
  DROPBOX_APP_KEY = get_secret("dropbox_app_key")
  
  MAILCHIMP_API_KEY = get_secret("mailchimp_api_key")
  
  # Twitter API credentials
  # Secrecy not required because its only used for R/O requests.
  # Please don't make us go over our rate limit.
  TWITTER_CONSUMER_KEY = get_secret("twitter_consumer_key")
  TWITTER_CONSUMER_SECRET = get_secret("twitter_consumer_secret")
  TWITTER_ACCESS_TOKEN_KEY = get_secret("twitter_access_token_key")
  TWITTER_ACCESS_TOKEN_SECRET = get_secret("twitter_access_token_secret")
  
  # These are the bots that Zulip sends automated messages as.
  INTERNAL_BOTS = [{'var_name': 'NOTIFICATION_BOT',
                    'email_template': 'notification-bot@%s',
                    'name': 'Notification Bot'},
                   {'var_name': 'EMAIL_GATEWAY_BOT',
                    'email_template': 'emailgateway@%s',
                    'name': 'Email Gateway'},
                   {'var_name': 'NAGIOS_SEND_BOT',
                    'email_template': 'nagios-send-bot@%s',
                    'name': 'Nagios Send Bot'},
                   {'var_name': 'NAGIOS_RECEIVE_BOT',
                    'email_template': 'nagios-receive-bot@%s',
                    'name': 'Nagios Receive Bot'},
                   {'var_name': 'WELCOME_BOT',
                    'email_template': 'welcome-bot@%s',
                    'name': 'Welcome Bot'}]
  
  # Bots that are created for each realm like the reminder-bot goes here.
  REALM_INTERNAL_BOTS = []  # type: List[Dict[str, str]]
  # These are realm-internal bots that may exist in some organizations,
  # so configure power the setting, but should not be auto-created at this time.
  DISABLED_REALM_INTERNAL_BOTS = [
      {'var_name': 'REMINDER_BOT',
       'email_template': 'reminder-bot@%s',
       'name': 'Reminder Bot'}
  ]
  
  if PRODUCTION:
      INTERNAL_BOTS += [
          {'var_name': 'NAGIOS_STAGING_SEND_BOT',
           'email_template': 'nagios-staging-send-bot@%s',
           'name': 'Nagios Staging Send Bot'},
          {'var_name': 'NAGIOS_STAGING_RECEIVE_BOT',
           'email_template': 'nagios-staging-receive-bot@%s',
           'name': 'Nagios Staging Receive Bot'},
      ]
  
  INTERNAL_BOT_DOMAIN = "zulip.com"
  
  # Set the realm-specific bot names
  for bot in INTERNAL_BOTS + REALM_INTERNAL_BOTS + DISABLED_REALM_INTERNAL_BOTS:
      if vars().get(bot['var_name']) is None:
          bot_email = bot['email_template'] % (INTERNAL_BOT_DOMAIN,)
          vars()[bot['var_name']] = bot_email
  
  ########################################################################
  # STATSD CONFIGURATION
  ########################################################################
  
  # Statsd is not super well supported; if you want to use it you'll need
  # to set STATSD_HOST and STATSD_PREFIX.
  if STATSD_HOST != '':
      INSTALLED_APPS += ['django_statsd']
      STATSD_PORT = 8125
      STATSD_CLIENT = 'django_statsd.clients.normal'
  
  ########################################################################
  # CAMO HTTPS CACHE CONFIGURATION
  ########################################################################
  
  if CAMO_URI != '':
      # This needs to be synced with the Camo installation
      CAMO_KEY = get_secret("camo_key")
  
  ########################################################################
  # STATIC CONTENT AND MINIFICATION SETTINGS
  ########################################################################
  
  STATIC_URL = '/static/'
  
  # ZulipStorage is a modified version of ManifestStaticFilesStorage,
  # and, like that class, it inserts a file hash into filenames
  # to prevent the browser from using stale files from cache.
  #
  # Unlike PipelineStorage, it requires the files to exist in
  # STATIC_ROOT even for dev servers.  So we only use
  # ZulipStorage when not DEBUG.
  
  if not DEBUG:
      STATICFILES_STORAGE = 'zerver.lib.storage.ZulipStorage'
      if PRODUCTION:
          STATIC_ROOT = '/home/zulip/prod-static'
      else:
          STATIC_ROOT = os.path.abspath(os.path.join(DEPLOY_ROOT, 'prod-static/serve'))
  
  # If changing this, you need to also the hack modifications to this in
  # our compilemessages management command.
  LOCALE_PATHS = (os.path.join(DEPLOY_ROOT, 'locale'),)
  
  # We want all temporary uploaded files to be stored on disk.
  FILE_UPLOAD_MAX_MEMORY_SIZE = 0
  
  STATICFILES_DIRS = ['static/']
  
  if DEBUG:
      WEBPACK_STATS_FILE = os.path.join('var', 'webpack-stats-dev.json')
  else:
      WEBPACK_STATS_FILE = 'webpack-stats-production.json'
  WEBPACK_LOADER = {
      'DEFAULT': {
          'CACHE': not DEBUG,
          'BUNDLE_DIR_NAME': 'webpack-bundles/',
          'STATS_FILE': os.path.join(DEPLOY_ROOT, WEBPACK_STATS_FILE),
      }
  }
  
  ########################################################################
  # TEMPLATES SETTINGS
  ########################################################################
  
  # List of callables that know how to import templates from various sources.
  LOADERS = [
      'django.template.loaders.filesystem.Loader',
      'django.template.loaders.app_directories.Loader',
  ]  # type: List[Union[str, Tuple[object, ...]]]
  if PRODUCTION:
      # Template caching is a significant performance win in production.
      LOADERS = [('django.template.loaders.cached.Loader', LOADERS)]
  
  base_template_engine_settings = {
      'BACKEND': 'django.template.backends.jinja2.Jinja2',
      'OPTIONS': {
          'environment': 'zproject.jinja2.environment',
          'extensions': [
              'jinja2.ext.i18n',
              'jinja2.ext.autoescape',
              'webpack_loader.contrib.jinja2ext.WebpackExtension',
          ],
          'context_processors': [
              'zerver.context_processors.zulip_default_context',
              'django.template.context_processors.i18n',
          ],
      },
  }  # type: Dict[str, Any]
  
  default_template_engine_settings = deepcopy(base_template_engine_settings)
  default_template_engine_settings.update({
      'NAME': 'Jinja2',
      'DIRS': [
          # The main templates directory
          os.path.join(DEPLOY_ROOT, 'templates'),
          # The webhook integration templates
          os.path.join(DEPLOY_ROOT, 'zerver', 'webhooks'),
          # The python-zulip-api:zulip_bots package templates
          os.path.join('static' if DEBUG else STATIC_ROOT, 'generated', 'bots'),
      ],
      'APP_DIRS': True,
  })
  
  non_html_template_engine_settings = deepcopy(base_template_engine_settings)
  non_html_template_engine_settings.update({
      'NAME': 'Jinja2_plaintext',
      'DIRS': [os.path.join(DEPLOY_ROOT, 'templates')],
      'APP_DIRS': False,
  })
  non_html_template_engine_settings['OPTIONS'].update({
      'autoescape': False,
      'trim_blocks': True,
      'lstrip_blocks': True,
  })
  
  # django-two-factor uses the default Django template engine (not Jinja2), so we
  # need to add config for it here.
  two_factor_template_options = deepcopy(default_template_engine_settings['OPTIONS'])
  del two_factor_template_options['environment']
  del two_factor_template_options['extensions']
  two_factor_template_options['loaders'] = ['zproject.settings.TwoFactorLoader']
  
  two_factor_template_engine_settings = {
      'NAME': 'Two_Factor',
      'BACKEND': 'django.template.backends.django.DjangoTemplates',
      'DIRS': [],
      'APP_DIRS': False,
      'OPTIONS': two_factor_template_options,
  }
  
  # The order here is important; get_template and related/parent functions try
  # the template engines in order until one succeeds.
  TEMPLATES = [
      default_template_engine_settings,
      non_html_template_engine_settings,
      two_factor_template_engine_settings,
  ]
  ########################################################################
  # LOGGING SETTINGS
  ########################################################################
  
  def zulip_path(path: str) -> str:
      if DEVELOPMENT:
          # if DEVELOPMENT, store these files in the Zulip checkout
          if path.startswith("/var/log"):
              path = os.path.join(DEVELOPMENT_LOG_DIRECTORY, os.path.basename(path))
          else:
              path = os.path.join(os.path.join(DEPLOY_ROOT, 'var'), os.path.basename(path))
      return path
  
  SERVER_LOG_PATH = zulip_path("/var/log/zulip/server.log")
  ERROR_FILE_LOG_PATH = zulip_path("/var/log/zulip/errors.log")
  MANAGEMENT_LOG_PATH = zulip_path("/var/log/zulip/manage.log")
  WORKER_LOG_PATH = zulip_path("/var/log/zulip/workers.log")
  JSON_PERSISTENT_QUEUE_FILENAME_PATTERN = zulip_path("/home/zulip/tornado/event_queues%s.json")
  EMAIL_LOG_PATH = zulip_path("/var/log/zulip/send_email.log")
  EMAIL_MIRROR_LOG_PATH = zulip_path("/var/log/zulip/email_mirror.log")
  EMAIL_DELIVERER_LOG_PATH = zulip_path("/var/log/zulip/email-deliverer.log")
  EMAIL_CONTENT_LOG_PATH = zulip_path("/var/log/zulip/email_content.log")
  LDAP_LOG_PATH = zulip_path("/var/log/zulip/ldap.log")
  LDAP_SYNC_LOG_PATH = zulip_path("/var/log/zulip/sync_ldap_user_data.log")
  QUEUE_ERROR_DIR = zulip_path("/var/log/zulip/queue_error")
  DIGEST_LOG_PATH = zulip_path("/var/log/zulip/digest.log")
  ANALYTICS_LOG_PATH = zulip_path("/var/log/zulip/analytics.log")
  ANALYTICS_LOCK_DIR = zulip_path("/home/zulip/deployments/analytics-lock-dir")
  API_KEY_ONLY_WEBHOOK_LOG_PATH = zulip_path("/var/log/zulip/webhooks_errors.log")
  WEBHOOK_UNEXPECTED_EVENTS_LOG_PATH = zulip_path("/var/log/zulip/webhooks_unexpected_events.log")
  SOFT_DEACTIVATION_LOG_PATH = zulip_path("/var/log/zulip/soft_deactivation.log")
  TRACEMALLOC_DUMP_DIR = zulip_path("/var/log/zulip/tracemalloc")
  SCHEDULED_MESSAGE_DELIVERER_LOG_PATH = zulip_path("/var/log/zulip/scheduled_message_deliverer.log")
  RETENTION_LOG_PATH = zulip_path("/var/log/zulip/message_retention.log")
  
  # The EVENT_LOGS feature is an ultra-legacy piece of code, which
  # originally logged all significant database changes for debugging.
  # We plan to replace it with RealmAuditLog, stored in the database,
  # everywhere that code mentioning it appears.
  if EVENT_LOGS_ENABLED:
      EVENT_LOG_DIR = zulip_path("/home/zulip/logs/event_log")  # type: Optional[str]
  else:
      EVENT_LOG_DIR = None
  
  ZULIP_WORKER_TEST_FILE = '/tmp/zulip-worker-test-file'
  
  
  if IS_WORKER:
      FILE_LOG_PATH = WORKER_LOG_PATH
  else:
      FILE_LOG_PATH = SERVER_LOG_PATH
  
  # This is disabled in a few tests.
  LOGGING_ENABLED = True
  
  DEFAULT_ZULIP_HANDLERS = (
      (['zulip_admins'] if ERROR_REPORTING else []) +
      ['console', 'file', 'errors_file']
  )
  
  LOGGING = {
      'version': 1,
      'disable_existing_loggers': False,
      'formatters': {
          'default': {
              '()': 'zerver.lib.logging_util.ZulipFormatter',
          }
      },
      'filters': {
          'ZulipLimiter': {
              '()': 'zerver.lib.logging_util.ZulipLimiter',
          },
          'EmailLimiter': {
              '()': 'zerver.lib.logging_util.EmailLimiter',
          },
          'require_debug_false': {
              '()': 'django.utils.log.RequireDebugFalse',
          },
          'require_debug_true': {
              '()': 'django.utils.log.RequireDebugTrue',
          },
          'nop': {
              '()': 'zerver.lib.logging_util.ReturnTrue',
          },
          'require_logging_enabled': {
              '()': 'zerver.lib.logging_util.ReturnEnabled',
          },
          'require_really_deployed': {
              '()': 'zerver.lib.logging_util.RequireReallyDeployed',
          },
          'skip_200_and_304': {
              '()': 'django.utils.log.CallbackFilter',
              'callback': zerver.lib.logging_util.skip_200_and_304,
          },
          'skip_site_packages_logs': {
              '()': 'django.utils.log.CallbackFilter',
              'callback': zerver.lib.logging_util.skip_site_packages_logs,
          },
      },
      'handlers': {
          'zulip_admins': {
              'level': 'ERROR',
              'class': 'zerver.logging_handlers.AdminNotifyHandler',
              'filters': (['ZulipLimiter', 'require_debug_false', 'require_really_deployed']
                          if not DEBUG_ERROR_REPORTING else []),
              'formatter': 'default'
          },
          'console': {
              'level': 'DEBUG',
              'class': 'logging.StreamHandler',
              'formatter': 'default'
          },
          'file': {
              'level': 'DEBUG',
              'class': 'logging.handlers.WatchedFileHandler',
              'formatter': 'default',
              'filename': FILE_LOG_PATH,
          },
          'errors_file': {
              'level': 'WARNING',
              'class': 'logging.handlers.WatchedFileHandler',
              'formatter': 'default',
              'filename': ERROR_FILE_LOG_PATH,
          },
          'ldap_file': {
              'level': 'DEBUG',
              'class': 'logging.handlers.WatchedFileHandler',
              'formatter': 'default',
              'filename': LDAP_LOG_PATH,
          },
      },
      'loggers': {
          # The Python logging module uses a hierarchy of logger names for config:
          # "foo.bar" has parent "foo" has parent "", the root.  But the semantics
          # are subtle: it walks this hierarchy once to find the log level to
          # decide whether to log the record at all, then a separate time to find
          # handlers to emit the record.
          #
          # For `level`, the most specific ancestor that has a `level` counts.
          # For `handlers`, the most specific ancestor that has a `handlers`
          # counts (assuming we set `propagate=False`, which we always do.)
          # These are independent -- they might come at the same layer, or
          # either one could come before the other.
          #
          # For `filters`, no ancestors count at all -- only the exact logger name
          # the record was logged at.
          #
          # Upstream docs: https://docs.python.org/3/library/logging
          #
          # Style rules:
          #  * Always set `propagate=False` if setting `handlers`.
          #  * Setting `level` equal to the parent is redundant; don't.
          #  * Setting `handlers` equal to the parent is redundant; don't.
          #  * Always write in order: level, filters, handlers, propagate.
  
          # root logger
          '': {
              'level': 'INFO',
              'filters': ['require_logging_enabled'],
              'handlers': DEFAULT_ZULIP_HANDLERS,
          },
  
          # Django, alphabetized
          'django': {
              # Django's default logging config has already set some
              # things on this logger.  Just mentioning it here causes
              # `logging.config` to reset it to defaults, as if never
              # configured; which is what we want for it.
          },
          'django.request': {
              # We set this to ERROR to prevent Django's default
              # low-value logs with lines like "Not Found: /robots.txt"
              # from being logged for every HTTP 4xx error at WARNING
              # level, which would otherwise end up spamming our
              # errors.log.  We'll still get logs in errors.log
              # including tracebacks for 5xx errors (i.e. Python
              # exceptions).
              'level': 'ERROR',
          },
          'django.security.DisallowedHost': {
              'handlers': ['file'],
              'propagate': False,
          },
          'django.server': {
              'filters': ['skip_200_and_304'],
              'handlers': ['console', 'file'],
              'propagate': False,
          },
          'django.template': {
              'level': 'DEBUG',
              'filters': ['require_debug_true', 'skip_site_packages_logs'],
              'handlers': ['console'],
              'propagate': False,
          },
  
          ## Uncomment the following to get all database queries logged to the console
          # 'django.db': {
          #     'level': 'DEBUG',
          #     'handlers': ['console'],
          #     'propagate': False,
          # },
  
          # other libraries, alphabetized
          'django_auth_ldap': {
              'level': 'DEBUG',
              'handlers': ['console', 'ldap_file', 'errors_file'],
              'propagate': False,
          },
          'pika.adapters': {
              # pika is super chatty on INFO.
              'level': 'WARNING',
              # pika spews a lot of ERROR logs when a connection fails.
              # We reconnect automatically, so those should be treated as WARNING --
              # write to the log for use in debugging, but no error emails/Zulips.
              'handlers': ['console', 'file', 'errors_file'],
              'propagate': False,
          },
          'pika.connection': {
              # Leave `zulip_admins` out of the handlers.  See pika.adapters above.
              'handlers': ['console', 'file', 'errors_file'],
              'propagate': False,
          },
          'requests': {
              'level': 'WARNING',
          },
  
          # our own loggers, alphabetized
          'zerver.lib.digest': {
              'level': 'DEBUG',
          },
          'zerver.management.commands.deliver_email': {
              'level': 'DEBUG',
          },
          'zerver.management.commands.enqueue_digest_emails': {
              'level': 'DEBUG',
          },
          'zerver.management.commands.deliver_scheduled_messages': {
              'level': 'DEBUG',
          },
          'zulip.ldap': {
              'level': 'DEBUG',
              'handlers': ['console', 'ldap_file', 'errors_file'],
              'propagate': False,
          },
          'zulip.management': {
              'handlers': ['file', 'errors_file'],
              'propagate': False,
          },
          'zulip.queue': {
              'level': 'WARNING',
          },
          'zulip.retention': {
              'handlers': ['file', 'errors_file'],
              'propagate': False,
          },
          'zulip.soft_deactivation': {
              'handlers': ['file', 'errors_file'],
              'propagate': False,
          },
          'zulip.zerver.lib.webhooks.common': {
              'level': 'DEBUG',
              'handlers': ['file', 'errors_file'],
              'propagate': False,
          },
          'zulip.zerver.webhooks': {
              'level': 'DEBUG',
              'handlers': ['file', 'errors_file'],
              'propagate': False,
          },
      }
  }  # type: Dict[str, Any]
  
  LOGIN_REDIRECT_URL = '/'
  
  # Client-side polling timeout for get_events, in milliseconds.
  # We configure this here so that the client test suite can override it.
  # We already kill the connection server-side with heartbeat events,
  # but it's good to have a safety.  This value should be greater than
  # (HEARTBEAT_MIN_FREQ_SECS + 10)
  POLL_TIMEOUT = 90 * 1000
  
  ########################################################################
  # SSO AND LDAP SETTINGS
  ########################################################################
  
  USING_APACHE_SSO = ('zproject.backends.ZulipRemoteUserBackend' in AUTHENTICATION_BACKENDS)
  
  if 'LDAP_DEACTIVATE_NON_MATCHING_USERS' not in vars():
      LDAP_DEACTIVATE_NON_MATCHING_USERS = (
          len(AUTHENTICATION_BACKENDS) == 1 and (AUTHENTICATION_BACKENDS[0] ==
                                                 "zproject.backends.ZulipLDAPAuthBackend"))
  
  if len(AUTHENTICATION_BACKENDS) == 1 and (AUTHENTICATION_BACKENDS[0] ==
                                            "zproject.backends.ZulipRemoteUserBackend"):
      HOME_NOT_LOGGED_IN = "/accounts/login/sso/"
      ONLY_SSO = True
  else:
      HOME_NOT_LOGGED_IN = '/login/'
      ONLY_SSO = False
  AUTHENTICATION_BACKENDS += ('zproject.backends.ZulipDummyBackend',)
  
  # Redirect to /devlogin/ by default in dev mode
  if DEVELOPMENT:
      HOME_NOT_LOGGED_IN = '/devlogin/'
      LOGIN_URL = '/devlogin/'
  
  POPULATE_PROFILE_VIA_LDAP = bool(AUTH_LDAP_SERVER_URI)
  
  if POPULATE_PROFILE_VIA_LDAP and \
     'zproject.backends.ZulipLDAPAuthBackend' not in AUTHENTICATION_BACKENDS:
      AUTHENTICATION_BACKENDS += ('zproject.backends.ZulipLDAPUserPopulator',)
  else:
      POPULATE_PROFILE_VIA_LDAP = (
          'zproject.backends.ZulipLDAPAuthBackend' in AUTHENTICATION_BACKENDS or
          POPULATE_PROFILE_VIA_LDAP)
  
  if POPULATE_PROFILE_VIA_LDAP:
      import ldap
      if (AUTH_LDAP_BIND_DN and ldap.OPT_REFERRALS not in AUTH_LDAP_CONNECTION_OPTIONS):
          # The default behavior of python-ldap (without setting option
          # `ldap.OPT_REFERRALS`) is to follow referrals, but anonymously.
          # If our original query was non-anonymous, that's unlikely to
          # work; skip the referral.
          #
          # The common case of this is that the server is Active Directory,
          # it's already given us the answer we need, and the referral is
          # just speculation about someplace else that has data our query
          # could in principle match.
          AUTH_LDAP_CONNECTION_OPTIONS[ldap.OPT_REFERRALS] = 0
  
  if REGISTER_LINK_DISABLED is None:
      # The default for REGISTER_LINK_DISABLED is a bit more
      # complicated: we want it to be disabled by default for people
      # using the LDAP backend that auto-creates users on login.
      if (len(AUTHENTICATION_BACKENDS) == 2 and
              ('zproject.backends.ZulipLDAPAuthBackend' in AUTHENTICATION_BACKENDS)):
          REGISTER_LINK_DISABLED = True
      else:
          REGISTER_LINK_DISABLED = False
  
  ########################################################################
  # SOCIAL AUTHENTICATION SETTINGS
  ########################################################################
  
  SOCIAL_AUTH_FIELDS_STORED_IN_SESSION = ['subdomain', 'is_signup', 'mobile_flow_otp', 'desktop_flow_otp',
                                          'multiuse_object_key']
  SOCIAL_AUTH_LOGIN_ERROR_URL = '/login/'
  
  SOCIAL_AUTH_GITHUB_SECRET = get_secret('social_auth_github_secret')
  SOCIAL_AUTH_GITLAB_SECRET = get_secret('social_auth_gitlab_secret')
  SOCIAL_AUTH_GITHUB_SCOPE = ['user:email']
  if SOCIAL_AUTH_GITHUB_ORG_NAME or SOCIAL_AUTH_GITHUB_TEAM_ID:
      SOCIAL_AUTH_GITHUB_SCOPE.append("read:org")
  SOCIAL_AUTH_GITHUB_ORG_KEY = SOCIAL_AUTH_GITHUB_KEY
  SOCIAL_AUTH_GITHUB_ORG_SECRET = SOCIAL_AUTH_GITHUB_SECRET
  SOCIAL_AUTH_GITHUB_TEAM_KEY = SOCIAL_AUTH_GITHUB_KEY
  SOCIAL_AUTH_GITHUB_TEAM_SECRET = SOCIAL_AUTH_GITHUB_SECRET
  
  SOCIAL_AUTH_GOOGLE_SECRET = get_secret('social_auth_google_secret')
  # Fallback to google-oauth settings in case social auth settings for
  # google are missing; this is for backwards-compatibility with older
  # Zulip versions where /etc/zulip/settings.py has not been migrated yet.
  GOOGLE_OAUTH2_CLIENT_SECRET = get_secret('google_oauth2_client_secret')
  SOCIAL_AUTH_GOOGLE_KEY = SOCIAL_AUTH_GOOGLE_KEY or GOOGLE_OAUTH2_CLIENT_ID
  SOCIAL_AUTH_GOOGLE_SECRET = SOCIAL_AUTH_GOOGLE_SECRET or GOOGLE_OAUTH2_CLIENT_SECRET
  
  if PRODUCTION:
      SOCIAL_AUTH_SAML_SP_PUBLIC_CERT = get_from_file_if_exists("/etc/zulip/saml/zulip-cert.crt")
      SOCIAL_AUTH_SAML_SP_PRIVATE_KEY = get_from_file_if_exists("/etc/zulip/saml/zulip-private-key.key")
  
  if "signatureAlgorithm" not in SOCIAL_AUTH_SAML_SECURITY_CONFIG:
      # If the configuration doesn't explicitly specify the algorithm,
      # we set RSA1 with SHA256 to override the python3-saml default, which uses
      # insecure SHA1.
      default_signature_alg = "http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"
      SOCIAL_AUTH_SAML_SECURITY_CONFIG["signatureAlgorithm"] = default_signature_alg
  
  for idp_name, idp_dict in SOCIAL_AUTH_SAML_ENABLED_IDPS.items():
      if DEVELOPMENT:
          idp_dict['entity_id'] = get_secret('saml_entity_id', '')
          idp_dict['url'] = get_secret('saml_url', '')
          idp_dict['x509cert_path'] = 'zproject/dev_saml.cert'
  
      # Set `x509cert` if not specified already; also support an override path.
      if 'x509cert' in idp_dict:
          continue
  
      if 'x509cert_path' in idp_dict:
          path = idp_dict['x509cert_path']
      else:
          path = "/etc/zulip/saml/idps/{}.crt".format(idp_name)
      idp_dict['x509cert'] = get_from_file_if_exists(path)
  
  SOCIAL_AUTH_PIPELINE = [
      'social_core.pipeline.social_auth.social_details',
      'zproject.backends.social_auth_associate_user',
      'zproject.backends.social_auth_finish',
  ]
  
  ########################################################################
  # EMAIL SETTINGS
  ########################################################################
  
  # Django setting. Not used in the Zulip codebase.
  DEFAULT_FROM_EMAIL = ZULIP_ADMINISTRATOR
  
  if EMAIL_BACKEND is not None:
      # If the server admin specified a custom email backend, use that.
      pass
  elif DEVELOPMENT:
      # In the dev environment, emails are printed to the run-dev.py console.
      EMAIL_BACKEND = 'zproject.email_backends.EmailLogBackEnd'
  elif not EMAIL_HOST:
      # If an email host is not specified, fail gracefully
      WARN_NO_EMAIL = True
      EMAIL_BACKEND = 'django.core.mail.backends.dummy.EmailBackend'
  else:
      EMAIL_BACKEND = 'django.core.mail.backends.smtp.EmailBackend'
  
  EMAIL_HOST_PASSWORD = get_secret('email_password')
  EMAIL_GATEWAY_PASSWORD = get_secret('email_gateway_password')
  AUTH_LDAP_BIND_PASSWORD = get_secret('auth_ldap_bind_password', '')
  
  ########################################################################
  # MISC SETTINGS
  ########################################################################
  
  if PRODUCTION:
      # Filter out user data
      DEFAULT_EXCEPTION_REPORTER_FILTER = 'zerver.filters.ZulipExceptionReporterFilter'
  
  # This is a debugging option only
  PROFILE_ALL_REQUESTS = False
  
  CROSS_REALM_BOT_EMAILS = {
      'notification-bot@zulip.com',
      'welcome-bot@zulip.com',
      'emailgateway@zulip.com',
  }
  
  THUMBOR_KEY = get_secret('thumbor_key')
  
  TWO_FACTOR_PATCH_ADMIN = False
  CONTRIBUTORS_DATA = os.path.join(STATIC_ROOT, 'generated/github-contributors.json')
  
  
  # allow cors request from all domains for demo propose
  # CORS_ORIGIN_ALLOW_ALL = True
  