Source code for swh.deposit.errors

# Copyright (C) 2017-2020  The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information

"""Module in charge of providing the standard sword errors

"""

import logging

from django.shortcuts import render
from rest_framework import status

FORBIDDEN = "forbidden"
UNAUTHORIZED = "unauthorized"
NOT_FOUND = "unknown"
BAD_REQUEST = "bad-request"
ERROR_CONTENT = "error-content"
CHECKSUM_MISMATCH = "checksum-mismatch"
MEDIATION_NOT_ALLOWED = "mediation-not-allowed"
METHOD_NOT_ALLOWED = "method-not-allowed"
MAX_UPLOAD_SIZE_EXCEEDED = "max_upload_size_exceeded"
PARSING_ERROR = "parsing-error"


logger = logging.getLogger(__name__)


[docs]class ParserError(ValueError): """Specific parsing error detected when parsing the xml metadata input """ pass
ERRORS = { FORBIDDEN: { "status": status.HTTP_403_FORBIDDEN, "iri": "http://purl.org/net/sword/error/ErrorForbidden", "tag": "sword:ErrorForbidden", }, UNAUTHORIZED: { "status": status.HTTP_401_UNAUTHORIZED, "iri": "http://purl.org/net/sword/error/ErrorUnauthorized", "tag": "sword:ErrorUnauthorized", }, NOT_FOUND: { "status": status.HTTP_404_NOT_FOUND, "iri": "http://purl.org/net/sword/error/ErrorNotFound", "tag": "sword:ErrorNotFound", }, ERROR_CONTENT: { "status": status.HTTP_415_UNSUPPORTED_MEDIA_TYPE, "iri": "http://purl.org/net/sword/error/ErrorContent", "tag": "sword:ErrorContent", }, CHECKSUM_MISMATCH: { "status": status.HTTP_412_PRECONDITION_FAILED, "iri": "http://purl.org/net/sword/error/ErrorChecksumMismatch", "tag": "sword:ErrorChecksumMismatch", }, BAD_REQUEST: { "status": status.HTTP_400_BAD_REQUEST, "iri": "http://purl.org/net/sword/error/ErrorBadRequest", "tag": "sword:ErrorBadRequest", }, PARSING_ERROR: { "status": status.HTTP_400_BAD_REQUEST, "iri": "http://purl.org/net/sword/error/ErrorBadRequest", "tag": "sword:ErrorBadRequest", }, MEDIATION_NOT_ALLOWED: { "status": status.HTTP_412_PRECONDITION_FAILED, "iri": "http://purl.org/net/sword/error/MediationNotAllowed", "tag": "sword:MediationNotAllowed", }, METHOD_NOT_ALLOWED: { "status": status.HTTP_405_METHOD_NOT_ALLOWED, "iri": "http://purl.org/net/sword/error/MethodNotAllowed", "tag": "sword:MethodNotAllowed", }, MAX_UPLOAD_SIZE_EXCEEDED: { "status": status.HTTP_413_REQUEST_ENTITY_TOO_LARGE, "iri": "http://purl.org/net/sword/error/MaxUploadSizeExceeded", "tag": "sword:MaxUploadSizeExceeded", }, }
[docs]def make_error_dict(key, summary=None, verbose_description=None): """Utility function to factorize error message dictionary. Args: key (str): Error status key referenced in swh.deposit.errors module summary (str/None): Error message clarifying the status verbose_description (str/None): A more verbose description or work around a potential problem. Returns: Dictionary with key 'error' detailing the 'status' and associated 'message' """ return { "error": { "key": key, "summary": summary, "verboseDescription": verbose_description, }, }
[docs]def make_error_response_from_dict(req, error): """Utility function to return an http response with error detail. Args: req (Request): original request error (dict): Error described as dict, typically generated from the make_error_dict function. Returns: HttpResponse with detailed error. """ error_information = ERRORS[error["key"]] context = error context.update(error_information) return render( req, "deposit/error.xml", context=error, content_type="application/xml", status=error_information["status"], )
[docs]def make_error_response(req, key, summary=None, verbose_description=None): """Utility function to create an http response with detailed error. Args: req (Request): original request key (str): Error status key referenced in swh.deposit.errors module summary (str): Error message clarifying the status verbose_description (str / None): A more verbose description or work around a potential problem. Returns: Dictionary with key 'error' detailing the 'status' and associated 'message' """ error = make_error_dict(key, summary, verbose_description) return make_error_response_from_dict(req, error["error"])
[docs]class DepositError(ValueError): """Represents an error that should be reported to the client """ def __init__(self, key, summary, verbose_description=None): self.key = key self.summary = summary self.verbose_description = verbose_description
[docs] def to_dict(self): return make_error_dict(self.key, self.summary, self.verbose_description)
[docs]class DepositErrorMiddleware: """A Django middleware that catches DepositError and returns a proper error response.""" # __init__ and __call__ are boilerplate to make a pass-through Django # middleware def __init__(self, get_response): self.get_response = get_response def __call__(self, request): response = self.get_response(request) return response
[docs] def process_exception(self, request, exception): if isinstance(exception, DepositError): logger.info( "%s %s -> %s('%s'):\n%s", request.method, request.path, exception.key, exception.summary, exception.verbose_description, ) return make_error_response_from_dict(request, exception.to_dict()["error"]) else: return None