Merge pull request #248 from dephell/env-vars-config

Configure DepHell by environment variables

dephell/commands/base.py

@@ -3,6 +3,7 @@
 import re
 from argparse import ArgumentParser
 from logging import getLogger
+from os import environ
 from pathlib import Path
 from typing import Dict, Set
 
@@ -12,7 +13,7 @@
 # app
 from ..actions import attach_deps, get_python_env
 from ..config import Config, config, get_data_dir
-from ..constants import CONFIG_NAMES, GLOBAL_CONFIG_NAME
+from ..constants import CONFIG_NAMES, ENV_VAR_TEMPLATE, GLOBAL_CONFIG_NAME
 from ..controllers import analyze_conflict
 from ..converters import CONVERTERS, InstalledConverter
 
@@ -39,6 +40,7 @@ def get_config(cls, args) -> Config:
         config.setup_logging()
         cls._attach_global_config_file()
         cls._attach_config_file(path=args.config, env=args.env)
+        config.attach_env_vars()
         config.attach_cli(args)
         config.setup_logging()
         return config
@@ -84,10 +86,18 @@ def _attach_global_config_file(cls) -> bool:
 
     @classmethod
     def _attach_config_file(cls, path, env) -> bool:
+        # get params from env vars if are not specified
+        if path is None:
+            path = environ.get(ENV_VAR_TEMPLATE.format('CONFIG'))
+        if env is None:
+            env = environ.get(ENV_VAR_TEMPLATE.format('ENV'), 'main')
+
+        # if path to config specified explicitly, just use it
         if path:
             config.attach_file(path=path, env=env)
             return True
 
+        # if path isn't specified, carefully try default names
         for path in CONFIG_NAMES:
             if not os.path.exists(path):
                 continue
@@ -136,7 +146,7 @@ def _resolve(self, resolver, default_envs: Set[str] = None):
                 return None
 
         # apply envs if needed
-        if 'envs' in self.config:
+        if self.config.get('envs'):
             resolver.apply_envs(set(self.config['envs']))
         elif default_envs:
             resolver.apply_envs(default_envs)

dephell/commands/venv_run.py

@@ -80,7 +80,7 @@ def __call__(self) -> bool:
         )
 
         # run
-        self.logger.info('running...')
+        self.logger.info('running...', extra=dict(command=command))
         with override_env_vars(env_vars):
             result = subprocess.run([str(executable)] + command[1:])
         if result.returncode != 0:

dephell/config/builders.py

@@ -17,7 +17,7 @@
 def build_config(parser):
     config_group = parser.add_argument_group('Configuration file')
     config_group.add_argument('-c', '--config', help='path to config file.')
-    config_group.add_argument('-e', '--env', default='main', help='environment in config.')
+    config_group.add_argument('-e', '--env', help='environment in config.')
 
 
 def build_from(parser):

dephell/config/manager.py

@@ -1,22 +1,29 @@
 # built-in
 import json
+import re
 from collections import defaultdict
+from copy import deepcopy
 from logging import captureWarnings
 from logging.config import dictConfig
+from os import environ
 from pathlib import Path
 from typing import Dict, Optional
 
 # external
 import tomlkit
 from cerberus import Validator
+from tomlkit.exceptions import TOMLKitError
 
 # app
-from ..constants import NON_PATH_FORMATS, SUFFIXES
+from ..constants import ENV_VAR_TEMPLATE, NON_PATH_FORMATS, SUFFIXES
 from .defaults import DEFAULT
 from .logging_config import LOGGING
 from .scheme import SCHEME
 
 
+ENV_VAR_REX = re.compile(ENV_VAR_TEMPLATE.format('(.+)'))
+
+
 class Config:
     env = ''
     _skip = (
@@ -26,7 +33,7 @@ class Config:
     )
 
     def __init__(self, data: Optional[dict] = None):
-        self._data = data or DEFAULT.copy()
+        self._data = data or deepcopy(DEFAULT)
 
     def setup_logging(self, data: Optional[dict] = None) -> None:
         captureWarnings(True)
@@ -133,6 +140,35 @@ def attach_cli(self, args, sep: str = '_') -> dict:
         self.attach(data)
         return dict(data)
 
+    def attach_env_vars(self, *, env_vars: Dict[str, str] = environ, sep: str = '_') -> dict:
+        data = defaultdict(dict)
+        for name, value in env_vars.items():
+            # drop templated part from name
+            match = ENV_VAR_REX.fullmatch(name)
+            if not match:
+                continue
+            name = match.groups()[0].lower()
+            if name in ('env', 'config'):
+                continue
+
+            # convert value to the correct type
+            try:
+                value = tomlkit.parse('key={}'.format(value))['key']
+            except TOMLKitError:
+                pass
+
+            # do the same as in `attach_cli`
+            parsed = name.split(sep, maxsplit=1)
+            if len(parsed) == 1:
+                data[name] = value
+            else:
+                # if old content isn't a dict, override it
+                if not isinstance(data[parsed[0]], dict):
+                    data[parsed[0]] = dict()
+                data[parsed[0]][parsed[1]] = value
+        self.attach(data)
+        return dict(data)
+
     def validate(self) -> bool:
         self._data = {k: v for k, v in self._data.items() if k not in self._skip}
         validator = Validator(SCHEME)

dephell/constants.py

@@ -18,6 +18,7 @@ class ReturnCodes(Enum):
 
 CONFIG_NAMES = ('poetry.toml', 'pyproject.toml')
 GLOBAL_CONFIG_NAME = 'config.toml'
+ENV_VAR_TEMPLATE = 'DEPHELL_{}'
 
 DEFAULT_WAREHOUSE = 'https://pypi.org/pypi/'
 WAREHOUSE_DOMAINS = {'pypi.org', 'pypi.python.org', 'test.pypi.org'}

docs/changelog.md

@@ -5,6 +5,7 @@ Follow [@PythonDepHell](https://twitter.com/PythonDepHell) on Twitter to get upd
 ## v.0.7.8 (WIP)
 
 + Fuzzy command name search ([#247](https://github.com/dephell/dephell/pull/247), [#122](https://github.com/dephell/dephell/issues/122)).
++ [Configure](config) DepHell with environment variables ([#248](https://github.com/dephell/dephell/pull/248)).
 
 ## v.0.7.7
 

docs/config.md

@@ -4,11 +4,12 @@ Dephell makes config from 3 layers:
 
 1. Default parameters.
 1. Section from config file.
+1. Environment variables.
 1. CLI arguments.
 
 ## Config file
 
-Config should be TOML file with `tool.dephell.ENV_NAME` sections (see [PEP-518](https://www.python.org/dev/peps/pep-0518/#tool-table)).
+Config should be [TOML](https://github.com/toml-lang/toml) file with `tool.dephell.ENV_NAME` sections (see [PEP-518](https://www.python.org/dev/peps/pep-0518/#tool-table)).
 
 1. By default, dephell tries to read `pyproject.toml` or `dephell.toml`. You can change it by `--config` argument.
 1. Default environment: `main`. Environment is the name of the section inside of `tool.dephell` section in config file. You can change environment by `--env` argument.
@@ -59,6 +60,50 @@ $ dephell venv run --env=pytest
 
 Also, by default, DepHell uses `--env` to generate path to the virtual environment, so different `--env` values have different virtual environments.
 
+## Environment variables
+
+Sometimes, specifying config parameters in environment variables can be more suitable for you. Most common case is to set up `env` or path to config file. For example:
+
+```bash
+export DEPHELL_ENV=flake8
+export DEPHELL_CONFIG="./project/dephell.toml"
+
+# commands below will be executed with specified above env and path to config
+dephell venv create
+dephell deps install
+dephell venv run
+
+# do not forget to remove variables after all
+unset DEPHELL_ENV
+unset DEPHELL_CONFIG
+```
+
+DepHell do type casting in the same way as [dynaconf](https://dynaconf.readthedocs.io/en/latest/guides/environment_variables.html#precedence-and-type-casting). Just use TOML syntax for values:
+
+```bash
+# Numbers
+DEPHELL_CACHE_TTL=42
+DEPHELL_SDIST_RATIO=0.5
+
+# Text
+DEPHELL_FROM_FORMAT=pip
+DEPHELL_FROM_FORMAT="pip"
+
+# Booleans
+DEPHELL_SILENT=true
+DEPHELL_SILENT=false
+
+# Use extra quotes to force a string from other type
+DEPHELL_PYTHON="'3.6'"
+DEPHELL_PROJECT="'true'"
+
+# Arrays
+DEPHELL_ENVS="['main', 'dev']"
+
+# Dictionaries
+DEPHELL_FROM='{format="pip", path="req.txt"}'
+```
+
 ## See also
 
 1. [`inspect config` command](cmd-inspect-config) to discover how dephell makes config for your project.

tests/test_config.py

@@ -1,6 +1,9 @@
 # built-in
 from pathlib import Path
 
+# external
+import pytest
+
 # project
 from dephell.config import Config
 
@@ -9,3 +12,23 @@ def test_load():
     config = Config()
     config.attach_file(path=str(Path('tests') / 'requirements' / 'dephell.toml'), env='some_env')
     assert config['from']['format'] == 'pip'
+
+
+@pytest.mark.parametrize('given, expected', [
+    ({'DEPHELL_COMMAND': 'pip'}, {'command': 'pip'}),
+    ({'DEPHELL_FROM_FORMAT': 'pip'}, {'from': {'format': 'pip'}}),
+    ({'SOME_JUNK': 'pip'}, {}),
+    ({'DEPHELL_ENV': 'pytest'}, {}),
+    ({'DEPHELL_CACHE_TTL': '10'}, {'cache': {'ttl': 10}}),
+    ({'DEPHELL_CACHE_TTL': '"10"'}, {'cache': {'ttl': '10'}}),
+    ({'DEPHELL_TRACEBACK': 'true'}, {'traceback': True}),
+    ({'DEPHELL_ENVS': '["main", "dev"]'}, {'envs': ['main', 'dev']}),
+    (
+        {'DEPHELL_FROM': '{format="pip", path="req.txt"}'},
+        {'from': {'format': 'pip', 'path': 'req.txt'}},
+    ),
+])
+def test_attach_env_vars(given, expected):
+    config = Config()
+    result = config.attach_env_vars(env_vars=given)
+    assert result == expected