Source code for habitat.views.utils

# Copyright 2011, 2012 (C) Adam Greig, Daniel Richman
#
# This file is part of habitat.
#
# habitat is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# habitat is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with habitat.  If not, see <http://www.gnu.org/licenses/>.

"""
Shared utility functions for views.
"""

import os
import json
import inspect
import re
import base64
import pytz

from couch_named_python import UnauthorizedError, ForbiddenError
from jsonschema import Validator
from strict_rfc3339 import validate_rfc3339

timestr_regex = re.compile(r"(\d\d):(\d\d):(\d\d)")

def read_json_schema(schemaname):
    mypath = os.path.dirname(inspect.getfile(inspect.currentframe()))
    path = os.path.join(mypath, "..", "..", "couchdb", "schemas", schemaname)
    with open(path) as f:
        schema = json.load(f)
    return schema

[docs]def must_be_admin(user, msg="Only server administrators may edit this document."): """Raise UnauthorizedError if the user is not an admin""" try: if '_admin' not in user['roles']: raise UnauthorizedError(msg) except (KeyError, TypeError): raise UnauthorizedError(msg)
def _validate_timestr(data): """Check that a time string is of the format HH:MM:SS""" m = timestr_regex.match(data) if m is None: return False hour, minute, second = [int(i) for i in m.groups()] return (0 <= hour <= 23 and 0 <= minute <= 59 and 0 <= second <= 60) def _validate_base64(data): """Check that a string is valid base64. Note: forbids whitespace""" try: decoded = base64.b64decode(data) except TypeError: return False # Some clients rely on the base64 not containing any whitespace. # b64encode produces a string without any whitespace, so... if base64.b64encode(decoded) != data: return False return True def _validate_timezone(data): """Check that a string is a valid Olson specifier""" return data in pytz.all_timezones def _validate_formats(data, schema): """Go through schema checking the formats date-time, time and base64""" if 'format' in schema: format_name = schema['format'] if format_name == "date-time" and not validate_rfc3339(data): raise ForbiddenError("A date-time was not in the required format.") elif format_name == "time" and not _validate_timestr(data): raise ForbiddenError("A time was not in the required format.") elif format_name == "base64" and not _validate_base64(data): raise ForbiddenError("A string was not valid base64.") elif format_name == "timezone" and not _validate_timezone(data): raise ForbiddenError("A string was not a valid timezone.") if 'properties' in schema and isinstance(schema['properties'], dict): for key, value in data.items(): try: _validate_formats(value, schema['properties'][key]) except (TypeError, KeyError): pass if 'additionalProperties' in schema: if isinstance(schema['additionalProperties'], dict): for value in data.values(): try: _validate_formats(value, schema['additionalProperties']) except TypeError: pass if 'items' in schema and isinstance(schema['items'], dict): for item in data: try: _validate_formats(item, schema['items']) except TypeError: pass
[docs]def validate_doc(data, schema): """Validate *data* against *schema*, raising descriptive errors""" v = Validator() errors = list(v.iter_errors(data, schema)) if errors: errors = ', '.join((str(error) for error in errors)) raise ForbiddenError("Validation errors: {0}".format(errors)) _validate_formats(data, schema)
def only_validates(doc_type): def decorator(func): def wrapped(new, old, userctx, secobj): new_type = new.get("type", None) new_deleted = new.get("_deleted", False) if old: old_type = old.get("type", None) else: old_type = None # sanity checks if old_type is None: assert old == {} or old is None if new_deleted: assert new_type is None if new_type == doc_type and old_type in [None, doc_type]: # new doc, or modified doc of correct type. validate: return func(new, old, userctx, secobj) elif new_deleted and old_type == doc_type: # deletion is managed by habitat.validate return elif new_type == doc_type or old_type == doc_type: # one or the other types match but not both, and not a new or deleted doc. raise ForbiddenError("You cannot change the type of a doc") else: # other type: not our business return # Be a well behaved decorator! wrapped.__name__ = func.__name__ wrapped.__doc__ = func.__doc__ wrapped.__dict__.update(func.__dict__) return wrapped return decorator