Better support for using variables which are a Path.

Author: adamghill

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.2.0
+
+- Better support for using variables which are a `Path`.
+
 ## 0.1.0
 
 - Load `pyproject.toml` and `django.toml` files and parse them.

README.md

@@ -5,11 +5,36 @@
 `dj-toml-settings` reads settings from a TOML file. By default, both `pyproject.toml` and `django.toml` files are parsed for settings in the `[tool.django]` namespace.
 
 ```toml
-# pyproject.toml
 [tool.django]
+BASE_DIR = { path = "." }
+SECRET_KEY = { env = "SECRET_KEY" }
+ADMIN_URL_PATH = { env = "ADMIN_URL_PATH", default="admin" }
+DEBUG = true
 ALLOWED_HOSTS = [
   "127.0.0.1",
 ]
+
+# Implicit dictionaries are supported
+# This is equivalent to `COLTRANE = { TITLE = "Example blog" }`
+[tool.django.COLTRANE]
+TITLE = "Example blog"
+
+# Any app name can be used for organizational purposes
+[tool.django.apps.tailwind-cli]
+TAILWIND_CLI_USE_DAISY_UI = true
+TAILWIND_CLI_SRC_CSS = ".django_tailwind_cli/source.css"
+
+# These settings are included when `ENVIRONMENT` environment variable is "development"
+[tool.django.envs.development]
+DEBUG = false
+ALLOWED_HOSTS = [
+  "example.localhost",
+]
+
+# These settings are included when `ENVIRONMENT` environment variable is "production"
+[tool.django.envs.production]
+DEBUG = false
+ALLOWED_HOSTS = { insert = "example.com" }
 ```
 
 ## Features 🤩
@@ -19,7 +44,6 @@ ALLOWED_HOSTS = [
 Use `${SOME_VARIABLE_NAME}` to use an existing setting as a value.
 
 ```toml
-# pyproject.toml
 [tool.django]
 GOOD_IPS = ["127.0.0.1"]
 ALLOWED_HOSTS = ${GOOD_IPS}
@@ -30,10 +54,6 @@ ALLOWED_HOSTS = ${GOOD_IPS}
 `[tool.django.apps.{ANY_NAME_HERE}]` sections of the TOML file can be used to group settings together. They can be named anything. They will override any settings in `[tool.django]`.
 
 ```toml
-# pyproject.toml
-[tool.django]
-ALLOWED_HOSTS = ["127.0.0.1"]
-
 [tool.django.apps.tailwind-cli]
 TAILWIND_CLI_USE_DAISY_UI = true
 TAILWIND_CLI_SRC_CSS = ".django_tailwind_cli/source.css"
@@ -44,7 +64,6 @@ TAILWIND_CLI_SRC_CSS = ".django_tailwind_cli/source.css"
 The `[tool.django.envs.{ENVIRONMENT_NAME}]` section of the TOML file will be used when `{ENVIRONMENT_NAME}` is set to the `ENVIRONMENT` environment variable. For example, `ENVIRONMENT=production python manage.py runserver` will load all settings in the `[tool.django.envs.production]` section. There settings will override any settings in `[tool.django.apps.*]` or `[tool.django]`.
 
 ```toml
-# pyproject.toml
 [tool.django]
 ALLOWED_HOSTS = ["127.0.0.1"]
 
@@ -59,10 +78,9 @@ ALLOWED_HOSTS = ["example.com"]
 
 ### Path
 
-Convert a string to a `Path` object. Handles relative paths based on the TOML file.
+Converts a string to a `Path` object. Handles relative paths based on the location of TOML file.
 
 ```toml
-# pyproject.toml
 [tool.django]
 BASE_DIR = { path = "." }
 PROJECT_DIR = { path = "./your_project_folder" }
@@ -74,7 +92,6 @@ REPOSITORY_DIR = { path = "./.." }
 Retrieve variables from the environment by using an `env` key. Specify an optional `default` key for a fallback value.
 
 ```toml
-# pyproject.toml
 [tool.django]
 EMAIL_HOST_PASSWORD = { env = 'SECRET_PASSWORD' }
 SECRET_KEY = { env = 'SECRET_KEY', default = 'this-is-a-secret' }
@@ -85,7 +102,6 @@ SECRET_KEY = { env = 'SECRET_KEY', default = 'this-is-a-secret' }
 Add items to an array by using the `insert` key.
 
 ```toml
-# pyproject.toml
 [tool.django]
 ALLOWED_HOSTS = { insert = '127.0.0.1' }
 ```

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "dj-toml-settings"
-version = "0.1.0"
+version = "0.2.0"
 description = "Load Django settings from a TOML file"
 authors = [
   { name = "Adam Hill", email = "adam@adamghill.com" },

src/dj_toml_settings/config.py

@@ -8,17 +8,16 @@
 
 
 @typechecked
-def get_toml_settings(base_dir: Path, data: dict | None = None, toml_settings_files: list | None = None) -> dict:
+def get_toml_settings(base_dir: Path, data: dict | None = None, toml_settings_files: list[str] | None = None) -> dict:
     """Gets the Django settings from the TOML files.
 
     TOML files to look in for settings:
     - pyproject.toml
     - django.toml
     """
-    toml_settings_files = toml_settings_files or TOML_SETTINGS_FILES
 
-    if data is None:
-        data = {}
+    toml_settings_files = toml_settings_files or TOML_SETTINGS_FILES
+    data = data or {}
 
     for settings_file_name in toml_settings_files:
         settings_path = base_dir / settings_file_name

src/dj_toml_settings/toml_parser.py

@@ -105,8 +105,17 @@ def parse_key_value(data: dict, key: str, value: Any, path: Path) -> dict:
     elif isinstance(value, str):
         # Handle variable substitution
         for match in re.finditer(r"\$\{[A-Z_0-9]+\}", value):
-            if variable := data.get(value[2:-1]):
-                value = value.replace(match.string, variable)
+            data_key = value[match.start() : match.end()][2:-1]
+
+            if variable := data.get(data_key):
+                if isinstance(variable, Path):
+                    # Take whatever is before/after the variable and put it together into a new Path
+                    start = value[: match.start()]
+                    ending = value[match.end() :]
+
+                    value = Path(start + str(variable) + ending)
+                else:
+                    value = value.replace(match.string, str(variable))
             else:
                 logger.warning(f"Missing variable substitution {value}")
 

tests/test_config/test_get_toml_settings.py

@@ -94,3 +94,34 @@ def test_no_files(tmp_path):
     actual = get_toml_settings(base_dir=tmp_path)
 
     assert expected == actual
+
+
+def test_data(tmp_path):
+    expected = {"DEBUG": False}
+
+    actual = get_toml_settings(base_dir=tmp_path, data={"DEBUG": False})
+
+    assert expected == actual
+
+
+def test_data_is_none(tmp_path):
+    expected = {}
+
+    actual = get_toml_settings(base_dir=tmp_path, data=None)
+
+    assert expected == actual
+
+
+def test_specified_file(tmp_path):
+    expected = {
+        "DEBUG": True,
+    }
+
+    (tmp_path / "blob.toml").write_text("""
+[tool.django]
+DEBUG = true
+""")
+
+    actual = get_toml_settings(base_dir=tmp_path, toml_settings_files=["blob.toml"])
+
+    assert expected == actual