halfapi/halfapi/half_domain.py

498 lines
16 KiB
Python

import importlib
import inspect
import os
import re
from packaging.specifiers import SpecifierSet
from packaging.version import Version
from typing import Coroutine, Dict, Iterator, List, Tuple
from types import ModuleType, FunctionType
from schema import SchemaError
from starlette.applications import Starlette
from starlette.routing import Router, Route
from starlette.schemas import SchemaGenerator
from .lib.responses import ORJSONResponse
from .lib.acl import AclRoute
import yaml
from . import __version__
from .lib.constants import API_SCHEMA_DICT, ROUTER_SCHEMA, VERBS
from .half_route import HalfRoute
from .lib import acl as lib_acl
from .lib.responses import PlainTextResponse
from .lib.routes import JSONRoute
from .lib.schemas import param_docstring_default
from .lib.domain import MissingAclError, PathError, UnknownPathParameterType, \
UndefinedRoute, UndefinedFunction, get_fct_name, route_decorator
from .lib.domain_middleware import DomainMiddleware
from .logging import logger
class HalfDomain(Starlette):
def __init__(self, domain, module=None, router=None, acl=None, app=None):
"""
Parameters:
domain (str): Module name (should be importable)
router (str): Router name (should be importable from domain module
defaults to __router__ variable from domain module)
app (HalfAPI): The app instance
"""
self.app = app
self.m_domain = importlib.import_module(domain) if module is None else module
self.d_domain = getattr(self.m_domain, 'domain', domain)
self.name = self.d_domain['name']
self.id = self.d_domain['id']
self.version = self.d_domain['version']
self.halfapi_version = self.d_domain.get('halfapi_version', __version__)
self.deps = self.d_domain.get('deps', tuple())
self.schema_components = self.d_domain.get('schema_components', dict())
if not router:
self.router = self.d_domain.get('routers', '.routers')
else:
self.router = router
self.m_router = None
try:
self.m_router = importlib.import_module(self.router, self.m_domain.__package__)
except AttributeError:
raise Exception('no router module')
self.m_acl = HalfDomain.m_acl(self.m_domain, acl)
self.config = { **app.config }
logger.info('HalfDomain creation %s %s', domain, self.config)
for elt in self.deps:
package, version = elt
specifier = SpecifierSet(version)
package_module = importlib.import_module(package)
if Version(package_module.__version__) not in specifier:
raise Exception(
'Wrong version for package {} version {} (excepting {})'.format(
package, package_module.__version__, specifier
))
super().__init__(
routes=self.gen_domain_routes(),
middleware=[
(DomainMiddleware, {
'domain': {
'name': self.name,
'id': self.id,
'version': self.version,
'halfapi_version': self.halfapi_version,
'config': self.config.get('domain', {}).get(self.name, {}).get('config', {})
}
})
]
)
@staticmethod
def name(module):
""" Returns the name declared in the 'domain' dict at the root of the package
"""
return module.domain['name']
@staticmethod
def m_acl(module, acl=None):
""" Returns the imported acl module for the domain module
"""
if not acl:
acl = getattr(module, '__acl__', '.acl')
return importlib.import_module(acl, module.__package__)
@staticmethod
def acls(module, acl=None):
""" Returns the ACLS constant for the given domain
"""
m_acl = HalfDomain.m_acl(module, acl)
try:
return [
lib_acl.ACL(*elt)
for elt in getattr(m_acl, 'ACLS')
]
except AttributeError as exc:
logger.error(exc)
raise Exception(
f'Missing acl.ACLS constant in module {m_acl.__package__}') from exc
@staticmethod
def acls_route(domain, module_path=None, acl=None):
""" Dictionary of acls
Format :
{
[acl_name]: {
callable: fct_reference,
docs: fct_docstring,
}
}
"""
d_res = {}
module = importlib.import_module(domain) \
if module_path is None \
else importlib.import_module(module_path)
m_acl = HalfDomain.m_acl(module, acl)
for elt in HalfDomain.acls(module, acl=acl):
fct = getattr(m_acl, elt.name)
d_res[elt.name] = {
'callable': fct,
'docs': elt.documentation
}
return d_res
@staticmethod
def acls_router(domain, module_path=None, acl=None):
""" Returns a Router object with the following routes :
/ : The "acls" field of the API metadatas
/{acl_name} : If the ACL is defined as public, a route that returns either status code 200 or 401 on HEAD/GET request
"""
routes = []
d_res = {}
module = importlib.import_module(domain) \
if module_path is None \
else importlib.import_module(module_path)
m_acl = HalfDomain.m_acl(module, acl)
for elt in HalfDomain.acls(module, acl=acl):
fct = getattr(m_acl, elt.name)
d_res[elt.name] = {
'callable': fct,
'docs': elt.documentation,
'public': elt.public
}
if elt.public:
routes.append(
AclRoute(f'/{elt.name}', fct, elt)
)
d_res_under_domain_name = {}
d_res_under_domain_name[HalfDomain.name(module)] = d_res
routes.append(
Route(
'/',
JSONRoute(d_res_under_domain_name),
methods=['GET']
)
)
return Router(routes)
@staticmethod
def gen_routes(m_router: ModuleType,
verb: str,
path: List[str],
params: List[Dict],
path_param_docstrings: Dict[str, str] = {}) -> Tuple[FunctionType, Dict]:
"""
Returns a tuple of the function associatied to the verb and path arguments,
and the dictionary of it's acls
Parameters:
- m_router (ModuleType): The module containing the function definition
- verb (str): The HTTP verb for the route (GET, POST, ...)
- path (List): The route path, as a list (each item being a level of
deepness), from the lowest level (domain) to the highest
- params (Dict): The acl list of the following format :
[{'acl': Function, 'args': {'required': [], 'optional': []}}]
Returns:
(Function, Dict): The destination function and the acl dictionary
"""
if len(params) == 0:
raise MissingAclError('[{}] {}'.format(verb, '/'.join(path)))
if len(path) == 0:
logger.error('Empty path for [{%s}]', verb)
raise PathError()
fct_name = get_fct_name(verb, path[-1])
if hasattr(m_router, fct_name):
fct = getattr(m_router, fct_name)
fct_docstring_obj = yaml.safe_load(fct.__doc__)
if 'parameters' not in fct_docstring_obj and path_param_docstrings:
fct_docstring_obj['parameters'] = list(map(
yaml.safe_load,
path_param_docstrings.values()))
fct.__doc__ = yaml.dump(fct_docstring_obj)
else:
raise UndefinedFunction('{}.{}'.format(m_router.__name__, fct_name or ''))
if not inspect.iscoroutinefunction(fct):
return route_decorator(fct), params
# TODO: Remove when using only sync functions
return lib_acl.args_check(fct), params
@staticmethod
def gen_router_routes(m_router, path: List[str], PATH_PARAMS={}) -> \
Iterator[Tuple[str, str, ModuleType, Coroutine, List]]:
"""
Recursive generator that parses a router (or a subrouter)
and yields from gen_routes
Parameters:
- m_router (ModuleType): The currently treated router module
- path (List[str]): The current path stack
Yields:
(str, str, ModuleType, Coroutine, List): A tuple containing the path, verb,
router module, function reference and parameters of the route.
Function and parameters are yielded from then gen_routes function,
that decorates the endpoint function.
"""
for subpath, params in HalfDomain.read_router(m_router).items():
path.append(subpath)
for verb in VERBS:
if verb not in params:
continue
yield ('/'.join(filter(lambda x: len(x) > 0, path)),
verb,
m_router,
*HalfDomain.gen_routes(m_router, verb, path, params[verb], PATH_PARAMS)
)
for subroute in params.get('SUBROUTES', []):
subroute_module = importlib.import_module(f'.{subroute}', m_router.__name__)
param_match = re.fullmatch('^([A-Z_]+)_([a-z]+)$', subroute)
parameter_name = None
if param_match is not None:
try:
parameter_name = param_match.groups()[0].lower()
if parameter_name in PATH_PARAMS:
raise Exception(f'Duplicate parameter name in same path! {subroute} : {parameter_name}')
parameter_type = param_match.groups()[1]
path.append('{{{}:{}}}'.format(
parameter_name,
parameter_type,
)
)
try:
PATH_PARAMS[parameter_name] = subroute_module.param_docstring
except AttributeError as exc:
PATH_PARAMS[parameter_name] = param_docstring_default(parameter_name, parameter_type)
except AssertionError as exc:
raise UnknownPathParameterType(subroute) from exc
else:
path.append(subroute)
try:
yield from HalfDomain.gen_router_routes(
subroute_module,
path,
PATH_PARAMS
)
except ImportError as exc:
logger.error('Failed to import subroute **{%s}**', subroute)
raise exc
path.pop()
if parameter_name:
PATH_PARAMS.pop(parameter_name)
path.pop()
@staticmethod
def read_router(m_router: ModuleType) -> Dict:
"""
Reads a module and returns a router dict
If the module has a "ROUTES" constant, it just returns this constant,
Else, if the module has an "ACLS" constant, it builds the accurate dict
TODO: May be another thing, may be not a part of halfAPI
"""
m_path = None
try:
if not hasattr(m_router, 'ROUTES'):
routes = {'':{}}
acls = getattr(m_router, 'ACLS') if hasattr(m_router, 'ACLS') else None
if acls is not None:
for method in acls.keys():
if method not in VERBS:
raise Exception(
'This method is not handled: {}'.format(method))
routes[''][method] = []
routes[''][method] = acls[method].copy()
routes['']['SUBROUTES'] = []
if hasattr(m_router, '__path__'):
""" Module is a package
"""
m_path = getattr(m_router, '__path__')
if isinstance(m_path, list) and len(m_path) == 1:
routes['']['SUBROUTES'] = [
elt.name
for elt in os.scandir(m_path[0])
if elt.is_dir()
]
else:
routes = getattr(m_router, 'ROUTES')
try:
ROUTER_SCHEMA.validate(routes)
except SchemaError as exc:
logger.error(routes)
raise exc
return routes
except ImportError as exc:
# TODO: Proper exception handling
raise exc
except FileNotFoundError as exc:
# TODO: Proper exception handling
logger.error(m_path)
raise exc
def gen_domain_routes(self):
"""
Yields the Route objects for a domain
Parameters:
m_domains: ModuleType
Returns:
Generator(HalfRoute)
"""
yield HalfRoute('/',
self.schema_openapi(),
[{'acl': lib_acl.public}],
'GET'
)
for path, method, m_router, fct, params in HalfDomain.gen_router_routes(self.m_router, []):
yield HalfRoute(f'/{path}', fct, params, method)
def schema_dict(self) -> Dict:
""" gen_router_routes return values as a dict
Parameters:
m_router (ModuleType): The domain routers' module
Returns:
Dict: Schema of dict is halfapi.lib.constants.DOMAIN_SCHEMA
@TODO: Should be a "router_schema_dict" function
"""
d_res = {}
for path, verb, m_router, fct, parameters in HalfDomain.gen_router_routes(self.m_router, []):
if path not in d_res:
d_res[path] = {}
if verb not in d_res[path]:
d_res[path][verb] = {}
d_res[path][verb]['callable'] = f'{m_router.__name__}:{fct.__name__}'
try:
d_res[path][verb]['docs'] = yaml.safe_load(fct.__doc__)
except AttributeError:
logger.error(
'Cannot read docstring from fct (fct=%s path=%s verb=%s', fct.__name__, path, verb)
d_res[path][verb]['acls'] = list(map(lambda elt: { **elt, 'acl': elt['acl'].__name__ },
parameters))
return d_res
def schema(self) -> Dict:
schema = { **API_SCHEMA_DICT }
schema['domain'] = {
'name': self.name,
'id': self.id,
'version': getattr(self.m_domain, '__version__', ''),
'patch_release': getattr(self.m_domain, '__patch_release__', ''),
'routers': self.m_router.__name__,
'acls': tuple(getattr(self.m_acl, 'ACLS', ()))
}
schema['paths'] = self.schema_dict()
return schema
def schema_openapi(self) -> Route:
schema = SchemaGenerator(
{
'openapi': '3.0.0',
'info': {
'title': self.name,
'version': self.version,
'x-acls': tuple(getattr(self.m_acl, 'ACLS', ())),
**({
f'x-{key}': value
for key, value in self.d_domain.items()
}),
},
'components': self.schema_components
}
)
async def inner(request, *args, **kwargs):
"""
description: |
Returns the current API routes description (OpenAPI v3)
as a JSON object
responses:
200:
description: API Schema in OpenAPI v3 format
"""
return ORJSONResponse(
schema.get_schema(routes=request.app.routes))
return inner