Refactor how the initial .env is created

Author: epicserve

config/env_writer.py

@@ -0,0 +1,120 @@
+import shutil
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import Any, Optional
+
+import environs
+
+
+class EnvWriter:
+    var_data: dict[str, Any]
+    write_dot_env_file: bool = False
+    base_dir: Path
+
+    def __init__(
+        self,
+        base_dir: Optional[Path] = None,
+        read_dot_env_file: bool = True,
+        eager: bool = True,
+        expand_vars: bool = False,
+    ):
+        self.var_data = {}
+        self._env = environs.Env(eager=eager, expand_vars=expand_vars)
+        self.write_dot_env_file = self._env.bool("WRITE_DOT_ENV_FILE", default=False)
+        self._env = environs.Env(eager=eager, expand_vars=expand_vars)
+        self.base_dir = environs.Path(__file__).parent if base_dir is None else base_dir  # type: ignore
+        if read_dot_env_file is True and self.write_dot_env_file is False:
+            self._env.read_env(str(self.base_dir.joinpath(".env")))
+
+    def _get_var(
+        self,
+        environs_instance,
+        var_type: str,
+        environ_args: tuple[Any, ...],
+        environ_kwargs: Optional[dict[str, Any]] = None,
+    ):
+        environ_kwargs = environ_kwargs or {}
+        help_text = environ_kwargs.pop("help_text", None)
+        initial = environ_kwargs.pop("initial", None)
+
+        if self.write_dot_env_file is True:
+            self.var_data[environ_args[0]] = {
+                "type": var_type,
+                "default": environ_kwargs.get("default"),
+                "help_text": help_text,
+                "initial": initial,
+            }
+
+        try:
+            return getattr(environs_instance, var_type)(*environ_args, **environ_kwargs)
+        except environs.EnvError as e:
+            if self.write_dot_env_file is False:
+                raise e
+
+    def __call__(self, *args, **kwargs):
+        return self._get_var(self._env, var_type="str", environ_args=args, environ_kwargs=kwargs)
+
+    def __getattr__(self, item):
+        allowed_methods = [
+            "int",
+            "bool",
+            "str",
+            "float",
+            "decimal",
+            "list",
+            "dict",
+            "json",
+            "datetime",
+            "date",
+            "time",
+            "path",
+            "log_level",
+            "timedelta",
+            "uuid",
+            "url",
+            "enum",
+            "dj_db_url",
+            "dj_email_url",
+            "dj_cache_url",
+        ]
+        if item not in allowed_methods:
+            return AttributeError(f"'{type(self).__name__}' object has no attribute '{item}'")
+
+        def _get_var(*args, **kwargs):
+            return self._get_var(self._env, var_type=item, environ_args=args, environ_kwargs=kwargs)
+
+        return _get_var
+
+    def write_env_file(self, env_file_path: Optional[Path] = None, overwrite_existing: bool = False):
+        if env_file_path is None:
+            env_file_path = self.base_dir.joinpath(".env")
+
+        if env_file_path.exists() is True and overwrite_existing is False:
+            backup_path = f"{env_file_path}.{datetime.now().strftime('%Y%m%d%H%M%S')}"
+            shutil.copy(env_file_path, backup_path)
+
+        with open(env_file_path, "w") as f:
+            env_str = (
+                f"# This is an initial .env file generated on {datetime.now(timezone.utc).isoformat()}. Any environment variable with a default\n"  # noqa: E501
+                "# can be safely removed or commented out. Any variable without a default must be set.\n\n"
+            )
+            for key, data in self.var_data.items():
+                initial = data.get("initial", None)
+                val = ""
+
+                if data["help_text"] is not None:
+                    env_str += f"# {data['help_text']}\n"
+                env_str += f"# type: {data['type']}\n"
+
+                if data["default"] is not None:
+                    env_str += f"# default: {data['default']}\n"
+
+                if initial is not None and val == "":
+                    val = initial()
+
+                if val == "" and data["default"] is not None:
+                    env_str += f"# {key}={val}\n\n"
+                else:
+                    env_str += f"{key}={val}\n\n"
+
+            f.write(env_str)

config/settings/_base.py

@@ -1,8 +1,9 @@
+import base64
+import os
 import socket
 
 import environs
-
-env = environs.Env()
+from config.env_writer import EnvWriter
 
 """
 Django settings for config project.
@@ -16,25 +17,28 @@
 
 BASE_DIR = environs.Path(__file__).parent.parent.parent  # type: ignore
 
-READ_DOT_ENV_FILE = env.bool("READ_DOT_ENV_FILE", default=True)
-
-if READ_DOT_ENV_FILE is True:
-    env.read_env(str(BASE_DIR.joinpath(".env")))
+env = EnvWriter(base_dir=BASE_DIR, read_dot_env_file=False)
 
 # Quick-start development settings - unsuitable for production
 # See https://docs.djangoproject.com/en/4.2/howto/deployment/checklist/
 
 # SECURITY WARNING: keep the secret key used in production secret!
-SECRET_KEY = env("SECRET_KEY")
+SECRET_KEY = env(
+    "SECRET_KEY",
+    initial=lambda: base64.b64encode(os.urandom(60)).decode(),
+    help_text="Django's SECRET_KEY used to provide cryptographic signing.",
+)
 
 # SECURITY WARNING: don't run with debug turned on in production!
-DEBUG = env.bool("DEBUG", default=False)
+DEBUG = env.bool("DEBUG", default=True, help_text="Set Django Debug mode to on or off")
 
-ALLOWED_HOSTS = env.list("ALLOWED_HOSTS", default=[])
-INTERNAL_IPS = env.list("INTERNAL_IPS", default=["127.0.0.1"])
+ALLOWED_HOSTS = env.list(
+    "ALLOWED_HOSTS", default=["127.0.0.1"], help_text="List of allowed hosts that this Django site can serve"
+)
+INTERNAL_IPS = env.list("INTERNAL_IPS", default=["127.0.0.1"], help_text="IPs allowed to run in debug mode")
 
 # Get the IP to use for Django Debug Toolbar when developing with docker
-if env.bool("USE_DOCKER", default=False) is True:
+if env.bool("USE_DOCKER", default=True, help_text="Used to set add the IP to INTERNAL_IPS for Docker Compose") is True:
     ip = socket.gethostbyname(socket.gethostname())
     INTERNAL_IPS += [ip[:-1] + "1"]
 
@@ -87,14 +91,15 @@
     },
 ]
 
-WSGI_APPLICATION = env("WSGI_APPLICATION", default="config.wsgi.application")
-DB_SSL_REQUIRED = env.bool("DB_SSL_REQUIRED", default=not DEBUG)
+WSGI_APPLICATION = env("WSGI_APPLICATION", default="config.wsgi.application", help_text="WSGI application to use")
 
 # Database
 # See https://github.com/jacobian/dj-database-url for more examples
 DATABASES = {
     "default": env.dj_db_url(
-        "DATABASE_URL", default=f'sqlite:///{BASE_DIR.joinpath("db.sqlite")}', ssl_require=DB_SSL_REQUIRED
+        "DATABASE_URL",
+        default="postgres://postgres:@db:5432/postgres",
+        help_text="Database URL for connecting to database",
     )
 }
 
@@ -144,7 +149,11 @@
 
 STORAGES = {
     "default": {
-        "BACKEND": env("DEFAULT_FILE_STORAGE", default="django.core.files.storage.FileSystemStorage"),
+        "BACKEND": env(
+            "DEFAULT_FILE_STORAGE",
+            default="django.core.files.storage.FileSystemStorage",
+            help_text="Default storage backend for media files",
+        ),
     },
     "staticfiles": {
         "BACKEND": "django.contrib.staticfiles.storage.StaticFilesStorage",
@@ -154,11 +163,13 @@
 
 if STORAGES["default"]["BACKEND"].endswith("MediaS3Storage") is True:
     STORAGES["staticfiles"]["BACKEND"] = env("STATICFILES_STORAGE")
-    AWS_ACCESS_KEY_ID = env("AWS_ACCESS_KEY_ID")
-    AWS_SECRET_ACCESS_KEY = env("AWS_SECRET_ACCESS_KEY")
-    AWS_STORAGE_BUCKET_NAME = env("AWS_STORAGE_BUCKET_NAME")
+    AWS_ACCESS_KEY_ID = env("AWS_ACCESS_KEY_ID", help_text="AWS Access Key ID if using S3 storage backend")
+    AWS_SECRET_ACCESS_KEY = env("AWS_SECRET_ACCESS_KEY", help_text="AWS Secret Access Key if using S3 storage backend")
+    AWS_STORAGE_BUCKET_NAME = env(
+        "AWS_STORAGE_BUCKET_NAME", help_text="AWS Storage Bucket Name if using S3 storage backend"
+    )
     AWS_DEFAULT_ACL = "public-read"
-    AWS_S3_REGION = env("AWS_S3_REGION", default="us-east-2")
+    AWS_S3_REGION = env("AWS_S3_REGION", default="us-east-2", help_text="AWS S3 Region if using S3 storage backend")
     AWS_S3_CUSTOM_DOMAIN = f"s3.{AWS_S3_REGION}.amazonaws.com/{AWS_STORAGE_BUCKET_NAME}"
     AWS_S3_OBJECT_PARAMETERS = {"CacheControl": "max-age=86400"}
     STATIC_URL = f"https://{AWS_S3_CUSTOM_DOMAIN}/static/"
@@ -180,11 +191,11 @@
 DEFAULT_AUTO_FIELD = "django.db.models.BigAutoField"
 
 # CACHE SETTINGS
-CACHE_URL = env("REDIS_URL", default="redis://redis:6379/0")
+REDIS_URL = env("REDIS_URL", default="redis://redis:6379/0", help_text="Redis URL for connecting to redis")
 CACHES = {
     "default": {
         "BACKEND": "django.core.cache.backends.redis.RedisCache",
-        "LOCATION": CACHE_URL,
+        "LOCATION": REDIS_URL,
     }
 }
 
@@ -193,7 +204,7 @@
 CRISPY_TEMPLATE_PACK = "bootstrap5"
 
 # CELERY SETTINGS
-CELERY_BROKER_URL = env("CACHE_URL", CACHE_URL)
+CELERY_BROKER_URL = REDIS_URL
 
 SESSION_ENGINE = "django.contrib.sessions.backends.cache"
 
@@ -228,6 +239,7 @@
 email = env.dj_email_url(
     "EMAIL_URL",
     default="smtp://[email protected]:[email protected]:587/?ssl=True&_default_from_email=President%20Skroob%20%[email protected]%3E",
+    help_text="URL used for setting Django's email settings",
 )
 DEFAULT_FROM_EMAIL = email["DEFAULT_FROM_EMAIL"]
 EMAIL_HOST = email["EMAIL_HOST"]

docker-compose.yml

@@ -12,6 +12,8 @@ services:
       - postgres_data:/var/lib/postgresql/data/
     ports:
       - "5432:5432"
+    env_file:
+      - .env
     environment:
       - POSTGRES_HOST_AUTH_METHOD=trust
 
@@ -45,6 +47,8 @@ services:
       - db
       - redis
 
+    env_file:
+      - .env
     environment:
       USE_DOCKER: 'on'
       DJANGO_SETTINGS_MODULE: config.settings
@@ -62,6 +66,8 @@ services:
     depends_on:
       - web
 
+    env_file:
+      - .env
     environment:
       DJANGO_SETTINGS_MODULE: config.settings
 
@@ -83,6 +89,8 @@ services:
     ports:
       - "3000:3000"
 
+    env_file:
+      - .env
     environment:
       NODE_ENV: development
 

justfile

@@ -40,6 +40,12 @@ reset := `tput -Txterm sgr0`
 @build_assets:
     {{ node_cmd_prefix }} npm run build
 
+# Create an initial .env file
+@create_env_file:
+    # Create an empty .env so that docker-compose doesn't fail
+    touch .env;
+    {{ python_cmd_prefix }} ./scripts/create_initial_env.py
+
 # Format SASS/CSS code
 @format_sass:
     just _start_msg "Formatting SASS code using stylelint"

scripts/create_initial_env.py

@@ -0,0 +1,13 @@
+#!/usr/bin/env python
+import os
+
+from django.core.management.color import make_style
+
+os.environ.setdefault("WRITE_DOT_ENV_FILE", "True")
+
+from config import settings  # noqa: E402
+
+style = make_style()
+
+settings.env.write_env_file()
+print(style.SUCCESS("Successfully created initial env file!"))

scripts/start_new_project

@@ -73,15 +73,8 @@ else
   cd $PROJECT_DIRECTORY
 fi
 
-SECRET_KEY=$(python -c "import random; print(''.join(random.SystemRandom().choice('abcdefghijklmnopqrstuvwxyz0123456789%^&*(-_=+)') for i in range(50)))")
-cat > .env <<EOF
-DEBUG=on
-SECRET_KEY='$SECRET_KEY'
-DATABASE_URL=postgres://postgres:@db:5432/postgres
-INTERNAL_IPS=127.0.0.1,0.0.0.0
-EOF
-
 just remove_extra_files
+just create_env_file
 find ./public -name ".keep" | xargs rm -rf
 
 echo ""