config_ninja.contrib.local
Use a local file as the backend.
Example
The following config-ninja settings file configures the LocalBackend to render two files
(/tmp/config-ninja/local/settings.json and /tmp/config-ninja/local/subset.toml) from a single
local source file (config-ninja-settings.yaml):
# the following top-level key is required
CONFIG_NINJA_OBJECTS:
# each second-level key identifies a config-ninja object
example-0:
# set the location that the object is written to
dest:
format: json
path: /tmp/config-ninja/local/settings.json
# specify where the object is stored / retrieved from
source:
backend: local
format: yaml
init:
kwargs:
path: config-ninja-settings.yaml
example-1:
dest:
# you can specify the path to a Jinja2 template:
format: templates/settings-subset.toml.j2
path: /tmp/config-ninja/local/subset.toml
source:
backend: local
format: yaml
new:
kwargs:
path: config-ninja-settings.yaml
1"""Use a local file as the backend. 2 3## Example 4 5The following `config-ninja`_ settings file configures the `LocalBackend` to render two files 6(`/tmp/config-ninja/local/settings.json` and `/tmp/config-ninja/local/subset.toml`) from a single 7local source file (`config-ninja-settings.yaml`): 8 9```yaml 10.. include:: ../../../examples/local-backend.yaml 11``` 12 13.. _config-ninja: https://bryant-finney.github.io/config-ninja/config_ninja.html 14""" 15 16from __future__ import annotations 17 18import logging 19import warnings 20from pathlib import Path 21from typing import AsyncIterator 22 23from watchfiles import awatch # pyright: ignore[reportUnknownVariableType] 24 25from config_ninja.backend import Backend 26 27__all__ = ['LocalBackend'] 28 29logger = logging.getLogger(__name__) 30 31 32class LocalBackend(Backend): 33 """Read the configuration from a local file. 34 35 ## Usage 36 37 >>> backend = LocalBackend(example_file) 38 >>> print(backend.get()) 39 key_0: value_0 40 key_1: 1 41 key_2: true 42 key_3: 43 - 1 44 - 2 45 - 3 46 """ 47 48 path: Path 49 """Read the configuration from this file""" 50 51 def __init__(self, path: str) -> None: 52 """Set attributes to initialize the backend. 53 54 If the given `path` doesn't exist, emit a warning and continue. 55 56 >>> with pytest.warns(RuntimeWarning): 57 ... backend = LocalBackend('does_not_exist') 58 """ 59 self.path = Path(path) 60 if not self.path.is_file(): 61 warnings.warn(f'could not read file: {path}', category=RuntimeWarning, stacklevel=2) 62 63 def get(self) -> str: 64 """Read the contents of the configuration file as a string.""" 65 return self.path.read_text(encoding='utf-8') 66 67 async def poll(self, interval: int = 0) -> AsyncIterator[str]: 68 """Poll the file's parent directory for changes, and yield the file contents on change. 69 70 .. note:: 71 The `interval` parameter is ignored 72 """ 73 yield self.get() 74 async for _ in awatch(self.path): 75 logger.info("detected change to '%s'", self.path) 76 yield self.get() 77 78 79logger.debug('successfully imported %s', __name__)
33class LocalBackend(Backend): 34 """Read the configuration from a local file. 35 36 ## Usage 37 38 >>> backend = LocalBackend(example_file) 39 >>> print(backend.get()) 40 key_0: value_0 41 key_1: 1 42 key_2: true 43 key_3: 44 - 1 45 - 2 46 - 3 47 """ 48 49 path: Path 50 """Read the configuration from this file""" 51 52 def __init__(self, path: str) -> None: 53 """Set attributes to initialize the backend. 54 55 If the given `path` doesn't exist, emit a warning and continue. 56 57 >>> with pytest.warns(RuntimeWarning): 58 ... backend = LocalBackend('does_not_exist') 59 """ 60 self.path = Path(path) 61 if not self.path.is_file(): 62 warnings.warn(f'could not read file: {path}', category=RuntimeWarning, stacklevel=2) 63 64 def get(self) -> str: 65 """Read the contents of the configuration file as a string.""" 66 return self.path.read_text(encoding='utf-8') 67 68 async def poll(self, interval: int = 0) -> AsyncIterator[str]: 69 """Poll the file's parent directory for changes, and yield the file contents on change. 70 71 .. note:: 72 The `interval` parameter is ignored 73 """ 74 yield self.get() 75 async for _ in awatch(self.path): 76 logger.info("detected change to '%s'", self.path) 77 yield self.get()
Read the configuration from a local file.
Usage
>>> backend = LocalBackend(example_file)
>>> print(backend.get())
key_0: value_0
key_1: 1
key_2: true
key_3:
- 1
- 2
- 3
LocalBackend(path: str)
52 def __init__(self, path: str) -> None: 53 """Set attributes to initialize the backend. 54 55 If the given `path` doesn't exist, emit a warning and continue. 56 57 >>> with pytest.warns(RuntimeWarning): 58 ... backend = LocalBackend('does_not_exist') 59 """ 60 self.path = Path(path) 61 if not self.path.is_file(): 62 warnings.warn(f'could not read file: {path}', category=RuntimeWarning, stacklevel=2)
Set attributes to initialize the backend.
If the given path doesn't exist, emit a warning and continue.
>>> with pytest.warns(RuntimeWarning):
... backend = LocalBackend('does_not_exist')
def
get(self) -> str:
64 def get(self) -> str: 65 """Read the contents of the configuration file as a string.""" 66 return self.path.read_text(encoding='utf-8')
Read the contents of the configuration file as a string.
async def
poll(self, interval: int = 0) -> AsyncIterator[str]:
68 async def poll(self, interval: int = 0) -> AsyncIterator[str]: 69 """Poll the file's parent directory for changes, and yield the file contents on change. 70 71 .. note:: 72 The `interval` parameter is ignored 73 """ 74 yield self.get() 75 async for _ in awatch(self.path): 76 logger.info("detected change to '%s'", self.path) 77 yield self.get()
Poll the file's parent directory for changes, and yield the file contents on change.
The interval parameter is ignored