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Source code for galaxy.web.framework.decorators
import logging
from functools import wraps
from inspect import getfullargspec
from json import loads
from traceback import format_exc
import paste.httpexceptions
from pydantic import BaseModel
from pydantic.error_wrappers import ValidationError
from galaxy.exceptions import (
error_codes,
MessageException,
RequestParameterInvalidException,
RequestParameterMissingException,
)
from galaxy.util import (
parse_non_hex_float,
unicodify,
)
from galaxy.util.json import safe_dumps
from galaxy.web.framework import url_for
log = logging.getLogger(__name__)
JSON_CONTENT_TYPE = "application/json; charset=UTF-8"
JSONP_CONTENT_TYPE = "application/javascript"
JSONP_CALLBACK_KEY = "callback"
# ----------------------------------------------------------------------------- web controller decorators
def _save_orig_fn(wrapped, orig):
if not hasattr(orig, "_orig"):
wrapped._orig = orig
return wrapped
[docs]def expose(func):
"""
Decorator: mark a function as 'exposed' and thus web accessible
"""
func.exposed = True
return func
[docs]def json(func, pretty=False):
"""
Format the response as JSON and set the response content type to
JSON_CONTENT_TYPE.
"""
@wraps(func)
def call_and_format(self, trans, *args, **kwargs):
# pull out any callback argument to the api endpoint and set the content type to json or javascript
jsonp_callback = kwargs.pop(JSONP_CALLBACK_KEY, None)
if jsonp_callback:
trans.response.set_content_type(JSONP_CONTENT_TYPE)
else:
trans.response.set_content_type(JSON_CONTENT_TYPE)
rval = func(self, trans, *args, **kwargs)
return format_return_as_json(rval, jsonp_callback, pretty=(pretty or trans.debug))
if not hasattr(func, "_orig"):
call_and_format._orig = func
return expose(_save_orig_fn(call_and_format, func))
[docs]def require_login(verb="perform this action", use_panels=False):
def argcatcher(func):
@wraps(func)
def decorator(self, trans, *args, **kwargs):
if trans.get_user():
return func(self, trans, *args, **kwargs)
else:
redirect_url = url_for(controller=trans.controller, action=trans.action)
query_string = trans.environ.get("QUERY_STRING", "")
if query_string:
redirect_url = f"{redirect_url}?{query_string}"
href = url_for(controller="login", redirect=redirect_url)
return trans.show_error_message(
f'You must be <a target="galaxy_main" href="{href}" class="require-login-link">logged in</a> to {verb}.',
use_panels=use_panels,
)
return decorator
return argcatcher
[docs]def require_admin(func):
@wraps(func)
def decorator(self, trans, *args, **kwargs):
if not trans.user_is_admin:
msg = require_admin_message(trans.app.config, trans.get_user())
trans.response.status = 403
content_type = trans.response.get_content_type()
# content_type for instance may be... application/json; charset=UTF-8
if "application/json" in content_type:
return __api_error_dict(trans, status_code=403, err_code=error_codes.ADMIN_REQUIRED, err_msg=msg)
else:
return trans.show_error_message(msg)
return func(self, trans, *args, **kwargs)
return decorator
[docs]def require_admin_message(config, user):
if not config.admin_users_list:
msg = "You must be logged in as an administrator to access this feature, but no administrators are set in the Galaxy configuration."
elif not user:
msg = "You must be logged in as an administrator to access this feature."
else:
msg = "You must be an administrator to access this feature."
return msg
[docs]def do_not_cache(func):
"""
Sets cache-prevention headers for the request.
"""
@wraps(func)
def set_nocache_headers(self, trans, *args, **kwargs):
trans.response.headers["Cache-Control"] = ["no-cache", "no-store", "must-revalidate"]
trans.response.headers["Pragma"] = "no-cache"
trans.response.headers["Expires"] = "0"
return func(self, trans, *args, **kwargs)
return set_nocache_headers
# ----------------------------------------------------------------------------- (original) api decorators
[docs]def legacy_expose_api(func, to_json=True, user_required=True):
"""
Expose this function via the API.
"""
@wraps(func)
def decorator(self, trans, *args, **kwargs):
def error(environ, start_response):
start_response(error_status, [("Content-type", "text/plain")])
return error_message
error_status = "403 Forbidden"
if trans.error_message:
return trans.error_message
if user_required and trans.anonymous:
error_message = "API Authentication Required for this request"
return error
if trans.request.is_body_readable:
try:
kwargs["payload"] = __extract_payload_from_request(trans, func, kwargs)
except ValueError:
error_status = "400 Bad Request"
error_message = "Your request did not appear to be valid JSON, please consult the API documentation"
return error
# pull out any callback argument to the api endpoint and set the content type to json or javascript
jsonp_callback = kwargs.pop(JSONP_CALLBACK_KEY, None)
if jsonp_callback:
trans.response.set_content_type(JSONP_CONTENT_TYPE)
else:
trans.response.set_content_type(JSON_CONTENT_TYPE)
# send 'do not cache' headers to handle IE's caching of ajax get responses
trans.response.headers["Cache-Control"] = "max-age=0,no-cache,no-store"
# Perform api_run_as processing, possibly changing identity
if "payload" in kwargs and isinstance(kwargs["payload"], dict) and "run_as" in kwargs["payload"]:
if not trans.user_can_do_run_as:
error_message = "User does not have permissions to run jobs as another user"
return error
try:
decoded_user_id = trans.security.decode_id(kwargs["payload"]["run_as"])
except TypeError:
trans.response.status = 400
return f"Malformed user id ( {str(kwargs['payload']['run_as'])} ) specified, unable to decode."
try:
user = trans.sa_session.query(trans.app.model.User).get(decoded_user_id)
trans.set_user(user)
except Exception:
trans.response.status = 400
return "That user does not exist."
try:
rval = func(self, trans, *args, **kwargs)
if to_json:
rval = format_return_as_json(rval, jsonp_callback, pretty=trans.debug)
return rval
except paste.httpexceptions.HTTPException:
raise # handled
except Exception:
log.exception("Uncaught exception in exposed API method:")
raise paste.httpexceptions.HTTPServerError()
return expose(_save_orig_fn(decorator, func))
def __extract_payload_from_request(trans, func, kwargs):
content_type = trans.request.headers.get("content-type", "")
if content_type.startswith("application/x-www-form-urlencoded") or content_type.startswith("multipart/form-data"):
# If the content type is a standard type such as multipart/form-data, the wsgi framework parses the request body
# and loads all field values into kwargs. However, kwargs also contains formal method parameters etc. which
# are not a part of the request body. This is a problem because it's not possible to differentiate between values
# which are a part of the request body, and therefore should be a part of the payload, and values which should not be
# in the payload. Therefore, the decorated method's formal arguments are discovered through reflection and removed from
# the payload dictionary. This helps to prevent duplicate argument conflicts in downstream methods.
payload = kwargs.copy()
named_args = getfullargspec(func).args
for arg in named_args:
payload.pop(arg, None)
for k, v in payload.items():
if isinstance(v, str):
try:
# note: parse_non_hex_float only needed here for single string values where something like
# 40000000000000e5 will be parsed as a scientific notation float. This is as opposed to hex strings
# in larger JSON structures where quoting prevents this (further below)
payload[k] = loads(v, parse_float=parse_non_hex_float)
except Exception:
# may not actually be json, just continue
pass
elif content_type == "application/offset+octet-stream":
return unicodify(trans.request.body)
else:
# Assume application/json content type and parse request body manually, since wsgi won't do it. However, the order of this check
# should ideally be in reverse, with the if clause being a check for application/json and the else clause assuming a standard encoding
# such as multipart/form-data. Leaving it as is for backward compatibility, just in case.
payload = loads(unicodify(trans.request.body))
run_as = trans.request.headers.get("run-as")
if run_as:
payload["run_as"] = run_as
return payload
[docs]def legacy_expose_api_raw(func):
"""
Expose this function via the API but don't dump the results
to JSON.
"""
return legacy_expose_api(func, to_json=False)
[docs]def legacy_expose_api_raw_anonymous(func):
"""
Expose this function via the API but don't dump the results
to JSON.
"""
return legacy_expose_api(func, to_json=False, user_required=False)
[docs]def legacy_expose_api_anonymous(func, to_json=True):
"""
Expose this function via the API but don't require a set user.
"""
return legacy_expose_api(func, to_json=to_json, user_required=False)
# ----------------------------------------------------------------------------- (new) api decorators
[docs]def expose_api(func, to_json=True, user_required=True, user_or_session_required=True, handle_jsonp=True):
"""
Expose this function via the API.
"""
@wraps(func)
def decorator(self, trans, *args, **kwargs):
# errors passed in from trans._authenticate_api
if trans.error_message:
return __api_error_response(
trans, status_code=403, err_code=error_codes.USER_NO_API_KEY, err_msg=trans.error_message
)
if trans.anonymous:
# error if anon and user required
if user_required:
return __api_error_response(
trans,
status_code=403,
err_code=error_codes.USER_NO_API_KEY,
err_msg="API authentication required for this request",
)
# error if anon and no session
if not trans.galaxy_session and user_or_session_required:
return __api_error_response(
trans,
status_code=403,
err_code=error_codes.USER_NO_API_KEY,
err_msg="API authentication or Galaxy session required for this request",
)
if trans.request.is_body_readable:
try:
kwargs["payload"] = __extract_payload_from_request(trans, func, kwargs)
except ValueError:
error_code = error_codes.USER_INVALID_JSON
return __api_error_response(trans, status_code=400, err_code=error_code)
# pull out any callback argument to the api endpoint and set the content type to json or javascript
# TODO: use handle_jsonp to NOT overwrite existing tool_shed JSONP
jsonp_callback = kwargs.pop(JSONP_CALLBACK_KEY, None) if handle_jsonp else None
if jsonp_callback:
trans.response.set_content_type(JSONP_CONTENT_TYPE)
else:
trans.response.set_content_type(JSON_CONTENT_TYPE)
# send 'do not cache' headers to handle IE's caching of ajax get responses
trans.response.headers["Cache-Control"] = "max-age=0,no-cache,no-store"
# TODO: Refactor next block out into a helper procedure.
# Perform api_run_as processing, possibly changing identity
if "payload" in kwargs and "run_as" in kwargs["payload"]:
if not trans.user_can_do_run_as:
error_code = error_codes.USER_CANNOT_RUN_AS
return __api_error_response(trans, err_code=error_code, status_code=403)
try:
decoded_user_id = trans.security.decode_id(kwargs["payload"]["run_as"])
except (TypeError, ValueError):
error_message = f"Malformed user id ( {str(kwargs['payload']['run_as'])} ) specified, unable to decode."
error_code = error_codes.USER_INVALID_RUN_AS
return __api_error_response(trans, err_code=error_code, err_msg=error_message, status_code=400)
try:
user = trans.sa_session.query(trans.app.model.User).get(decoded_user_id)
trans.set_user(user)
except Exception:
error_code = error_codes.USER_INVALID_RUN_AS
return __api_error_response(trans, err_code=error_code, status_code=400)
try:
try:
rval = func(self, trans, *args, **kwargs)
except ValidationError as e:
raise validation_error_to_message_exception(e)
if to_json:
rval = format_return_as_json(rval, jsonp_callback, pretty=trans.debug)
return rval
except MessageException as e:
traceback_string = format_exc()
return __api_error_response(trans, exception=e, traceback=traceback_string)
except paste.httpexceptions.HTTPException:
# TODO: Allow to pass or format for the API???
raise # handled
except Exception as e:
traceback_string = format_exc()
error_message = "Uncaught exception in exposed API method:"
log.exception(error_message)
return __api_error_response(
trans,
status_code=500,
exception=e,
traceback=traceback_string,
err_msg=error_message,
err_code=error_codes.UNKNOWN,
)
if not hasattr(func, "_orig"):
decorator._orig = func
decorator.exposed = True
return decorator
[docs]def format_return_as_json(rval, jsonp_callback=None, pretty=False):
"""
Formats a return value as JSON or JSONP if `jsonp_callback` is present.
Use `pretty=True` to return pretty printed json.
"""
dumps_kwargs = dict(indent=4, sort_keys=True) if pretty else {}
if isinstance(rval, BaseModel):
json = rval.json(**dumps_kwargs)
else:
json = safe_dumps(rval, **dumps_kwargs)
if jsonp_callback:
json = f"{jsonp_callback}({json});"
return json
[docs]def validation_error_to_message_exception(e: ValidationError) -> MessageException:
invalid_found = False
missing_found = False
for error in e.errors():
if error["type"] == "value_error.missing" or error["type"] == "type_error.none.not_allowed":
missing_found = True
elif error["type"].startswith("type_error"):
invalid_found = True
if missing_found and not invalid_found:
return RequestParameterMissingException(str(e), validation_errors=loads(e.json()))
else:
return RequestParameterInvalidException(str(e), validation_errors=loads(e.json()))
[docs]def api_error_message(trans, **kwds):
exception = kwds.get("exception", None)
if exception:
# If we are passed a MessageException use err_msg.
default_error_code = getattr(exception, "err_code", error_codes.UNKNOWN)
default_error_message = getattr(exception, "err_msg", default_error_code.default_error_message)
extra_error_info = getattr(exception, "extra_error_info", {})
if not isinstance(extra_error_info, dict):
extra_error_info = {}
else:
default_error_message = "Error processing API request."
default_error_code = error_codes.UNKNOWN
extra_error_info = {}
traceback_string = kwds.get("traceback", "No traceback available.")
err_msg = kwds.get("err_msg", default_error_message)
error_code_object = kwds.get("err_code", default_error_code)
try:
error_code = error_code_object.code
except AttributeError:
# Some sort of bad error code sent in, logic failure on part of
# Galaxy developer.
error_code = error_codes.UNKNOWN.code
# Would prefer the terminology of error_code and error_message, but
# err_msg used a good number of places already. Might as well not change
# it?
error_response = dict(err_msg=err_msg, err_code=error_code, **extra_error_info)
if trans and trans.debug: # TODO: Should admins get to see traceback as well?
error_response["traceback"] = traceback_string
return error_response
def __api_error_dict(trans, **kwds):
error_dict = api_error_message(trans, **kwds)
exception = kwds.get("exception", None)
# If we are given an status code directly - use it - otherwise check
# the exception for a status_code attribute.
if "status_code" in kwds:
status_code = int(kwds.get("status_code"))
elif hasattr(exception, "status_code"):
status_code = int(exception.status_code)
else:
status_code = 500
response = trans.response
if not response.status or str(response.status).startswith("20"):
# Unset status code appears to be string '200 OK', if anything
# non-success (i.e. not 200 or 201) has been set, do not override
# underlying controller.
response.status = status_code
return error_dict
def __api_error_response(trans, **kwds):
error_dict = __api_error_dict(trans, **kwds)
return safe_dumps(error_dict)
[docs]def expose_api_anonymous(func, to_json=True):
"""
Expose this function via the API but don't require a set user.
"""
return expose_api(func, to_json=to_json, user_required=False)
[docs]def expose_api_anonymous_and_sessionless(func, to_json=True):
"""
Expose this function via the API but don't require a user or a galaxy_session.
"""
return expose_api(func, to_json=to_json, user_required=False, user_or_session_required=False)
[docs]def expose_api_raw_anonymous(func):
return expose_api(func, to_json=False, user_required=False)
[docs]def expose_api_raw_anonymous_and_sessionless(func):
# TODO: tool_shed api implemented JSONP first on a method-by-method basis, don't overwrite that for now
return expose_api(func, to_json=False, user_required=False, user_or_session_required=False, handle_jsonp=False)