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d439dc1 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 | # -*- coding: utf-8 -*-
# MinIO Python Library for Amazon S3 Compatible Cloud Storage, (C)
# 2015, 2016 MinIO, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
minio.post_policy
~~~~~~~~~~~~~~~
This module contains :class:`PostPolicy <PostPolicy>` implementation.
:copyright: (c) 2015 by MinIO, Inc.
:license: Apache 2.0, see LICENSE for more details.
"""
import base64
import datetime
import json
from .helpers import check_bucket_name, check_non_empty_string
# Policy explanation:
# http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-HTTPPOSTConstructPolicy.html
class PostPolicy:
"""
A :class:`PostPolicy <PostPolicy>` object for constructing
Amazon S3 POST policy JSON string.
"""
def __init__(self):
self._expiration = None
self._content_length_range = tuple()
# publicly accessible
self.policies = []
self.form_data = dict()
self.bucket_name = ''
self.key = ''
def set_expires(self, time):
"""
Set expiration time :class:`datetime.datetime`.
:param time: set expiration :class:`datetime.datetime`.
"""
if time.toordinal() < 1:
ValueError()
self._expiration = time
def set_key(self, key):
"""
Set key policy condition.
:param key: set key name.
"""
check_non_empty_string(key)
self.policies.append(('eq', '$key', key))
self.form_data['key'] = key
self.key = key
def set_key_startswith(self, key_startswith):
"""
Set key startswith policy condition.
:param key_startswith: set key prefix name.
"""
check_non_empty_string(key_startswith)
self.policies.append(('starts-with', '$key', key_startswith))
self.form_data['key'] = key_startswith
def set_bucket_name(self, bucket_name):
"""
Set bucket name policy condition.
:param bucket_name: set bucket name.
"""
check_bucket_name(bucket_name)
self.policies.append(('eq', '$bucket', bucket_name))
self.form_data['bucket'] = bucket_name
self.bucket_name = bucket_name
def set_content_type(self, content_type):
"""
Set content-type policy condition.
:param content_type: set content type name.
"""
self.policies.append(('eq', '$Content-Type', content_type))
self.form_data['Content-Type'] = content_type
def set_content_length_range(self, min_length, max_length):
"""
Set content length range policy condition.
Raise :exc:`ValueError` for invalid inputs.
:param min_length: Minimum length limit for content size.
:param max_length: Maximum length limit for content size.
"""
err_msg = ('Min-length ({}) must be <= Max-length ({}), '
'and they must be non-negative.').format(
min_length, max_length)
if min_length > max_length or min_length < 0 or max_length < 0:
raise ValueError(err_msg)
self._content_length_range = (min_length, max_length)
def append_policy(self, condition, target, value):
"""Append policy."""
self.policies.append([condition, target, value])
def _marshal_json(self, extras=()):
"""
Marshal various policies into json str/bytes.
"""
policies = self.policies[:]
policies.extend(extras)
if self._content_length_range:
policies.append(['content-length-range'] +
list(self._content_length_range))
policy_stmt = {
"expiration": self._expiration.strftime("%Y-%m-%dT%H:%M:%S.000Z"),
}
if policies:
policy_stmt["conditions"] = policies
return json.dumps(policy_stmt)
def base64(self, extras=()):
"""
Encode json into base64.
"""
data = self._marshal_json(extras=extras)
if not isinstance(data, bytes):
data = data.encode('utf-8')
b64enc = base64.b64encode(data)
return b64enc.decode('utf-8') if isinstance(b64enc, bytes) else b64enc
def is_valid(self):
"""
Validate for required parameters.
"""
if not isinstance(self._expiration, datetime.datetime):
raise ValueError("Expiration datetime must be specified.")
if 'key' not in self.form_data:
raise ValueError("object key must be specified.")
if 'bucket' not in self.form_data:
raise ValueError("bucket name must be specified.")
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