sanic/sanic/config.py
2019-01-02 23:28:05 +01:00

133 lines
4.2 KiB
Python

import os
import types
from distutils.util import strtobool
from sanic.exceptions import PyFileError
SANIC_PREFIX = "SANIC_"
BASE_LOGO = """
Sanic
Build Fast. Run Fast.
"""
DEFAULT_CONFIG = {
"REQUEST_MAX_SIZE": 100000000, # 100 megabytes
"REQUEST_BUFFER_QUEUE_SIZE": 100,
"REQUEST_TIMEOUT": 60, # 60 seconds
"RESPONSE_TIMEOUT": 60, # 60 seconds
"KEEP_ALIVE": True,
"KEEP_ALIVE_TIMEOUT": 5, # 5 seconds
"WEBSOCKET_MAX_SIZE": 2 ** 20, # 1 megabytes
"WEBSOCKET_MAX_QUEUE": 32,
"WEBSOCKET_READ_LIMIT": 2 ** 16,
"WEBSOCKET_WRITE_LIMIT": 2 ** 16,
"GRACEFUL_SHUTDOWN_TIMEOUT": 15.0, # 15 sec
"ACCESS_LOG": True,
}
class Config(dict):
def __init__(self, defaults=None, load_env=True, keep_alive=None):
defaults = defaults or {}
super().__init__({**DEFAULT_CONFIG, **defaults})
self.LOGO = BASE_LOGO
if keep_alive is not None:
self.KEEP_ALIVE = keep_alive
if load_env:
prefix = SANIC_PREFIX if load_env is True else load_env
self.load_environment_vars(prefix=prefix)
def __getattr__(self, attr):
try:
return self[attr]
except KeyError as ke:
raise AttributeError("Config has no '{}'".format(ke.args[0]))
def __setattr__(self, attr, value):
self[attr] = value
def from_envvar(self, variable_name):
"""Load a configuration from an environment variable pointing to
a configuration file.
:param variable_name: name of the environment variable
:return: bool. ``True`` if able to load config, ``False`` otherwise.
"""
config_file = os.environ.get(variable_name)
if not config_file:
raise RuntimeError(
"The environment variable %r is not set and "
"thus configuration could not be loaded." % variable_name
)
return self.from_pyfile(config_file)
def from_pyfile(self, filename):
"""Update the values in the config from a Python file.
Only the uppercase variables in that module are stored in the config.
:param filename: an absolute path to the config file
"""
module = types.ModuleType("config")
module.__file__ = filename
try:
with open(filename) as config_file:
exec(
compile(config_file.read(), filename, "exec"),
module.__dict__,
)
except IOError as e:
e.strerror = "Unable to load configuration file (%s)" % e.strerror
raise
except Exception as e:
raise PyFileError(filename) from e
self.from_object(module)
return True
def from_object(self, obj):
"""Update the values from the given object.
Objects are usually either modules or classes.
Just the uppercase variables in that object are stored in the config.
Example usage::
from yourapplication import default_config
app.config.from_object(default_config)
You should not use this function to load the actual configuration but
rather configuration defaults. The actual config should be loaded
with :meth:`from_pyfile` and ideally from a location not within the
package because the package might be installed system wide.
:param obj: an object holding the configuration
"""
for key in dir(obj):
if key.isupper():
self[key] = getattr(obj, key)
def load_environment_vars(self, prefix=SANIC_PREFIX):
"""
Looks for prefixed environment variables and applies
them to the configuration if present.
"""
for k, v in os.environ.items():
if k.startswith(prefix):
_, config_key = k.split(prefix, 1)
try:
self[config_key] = int(v)
except ValueError:
try:
self[config_key] = float(v)
except ValueError:
try:
self[config_key] = bool(strtobool(v))
except ValueError:
self[config_key] = v