# Copyright (c) 2006-2012 Mitch Garnaat http://garnaat.org/ # Copyright (c) 2010, Eucalyptus Systems, Inc. # Copyright (c) 2012 Amazon.com, Inc. or its affiliates. # All rights reserved. # # Permission is hereby granted, free of charge, to any person obtaining a # copy of this software and associated documentation files (the # "Software"), to deal in the Software without restriction, including # without limitation the rights to use, copy, modify, merge, publish, dis- # tribute, sublicense, and/or sell copies of the Software, and to permit # persons to whom the Software is furnished to do so, subject to the fol- # lowing conditions: # # The above copyright notice and this permission notice shall be included # in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS # OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL- # ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT # SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, # WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS # IN THE SOFTWARE. # # Parts of this code were copied or derived from sample code supplied by AWS. # The following notice applies to that code. # # This software code is made available "AS IS" without warranties of any # kind. You may copy, display, modify and redistribute the software # code either by itself or as incorporated into your code; provided that # you do not remove any proprietary notices. Your use of this software # code is at your own risk and you waive any claim against Amazon # Digital Services, Inc. or its affiliates with respect to your use of # this software code. (c) 2006 Amazon Digital Services, Inc. or its # affiliates. """ Some handy utility functions used by several classes. """ import subprocess import time import logging.handlers import boto import boto.provider import tempfile import random import smtplib import datetime import re import email.mime.multipart import email.mime.base import email.mime.text import email.utils import email.encoders import gzip import threading import locale from boto.compat import six, StringIO, urllib, encodebytes from contextlib import contextmanager from hashlib import md5, sha512 _hashfn = sha512 from boto.compat import json try: from boto.compat.json import JSONDecodeError except ImportError: JSONDecodeError = ValueError # List of Query String Arguments of Interest qsa_of_interest = ['acl', 'cors', 'defaultObjectAcl', 'location', 'logging', 'partNumber', 'policy', 'requestPayment', 'torrent', 'versioning', 'versionId', 'versions', 'website', 'uploads', 'uploadId', 'response-content-type', 'response-content-language', 'response-expires', 'response-cache-control', 'response-content-disposition', 'response-content-encoding', 'delete', 'lifecycle', 'tagging', 'restore', # storageClass is a QSA for buckets in Google Cloud Storage. # (StorageClass is associated to individual keys in S3, but # having it listed here should cause no problems because # GET bucket?storageClass is not part of the S3 API.) 'storageClass', # websiteConfig is a QSA for buckets in Google Cloud # Storage. 'websiteConfig', # compose is a QSA for objects in Google Cloud Storage. 'compose', # billing is a QSA for buckets in Google Cloud Storage. 'billing', # userProject is a QSA for requests in Google Cloud Storage. 'userProject', # encryptionConfig is a QSA for requests in Google Cloud # Storage. 'encryptionConfig'] _first_cap_regex = re.compile('(.)([A-Z][a-z]+)') _number_cap_regex = re.compile('([a-z])([0-9]+)') _end_cap_regex = re.compile('([a-z0-9])([A-Z])') def unquote_v(nv): if len(nv) == 1: return nv else: return (nv[0], urllib.parse.unquote(nv[1])) def canonical_string(method, path, headers, expires=None, provider=None): """ Generates the aws canonical string for the given parameters """ if not provider: provider = boto.provider.get_default() interesting_headers = {} for key in headers: lk = key.lower() if headers[key] is not None and \ (lk in ['content-md5', 'content-type', 'date'] or lk.startswith(provider.header_prefix)): interesting_headers[lk] = str(headers[key]).strip() # these keys get empty strings if they don't exist if 'content-type' not in interesting_headers: interesting_headers['content-type'] = '' if 'content-md5' not in interesting_headers: interesting_headers['content-md5'] = '' # just in case someone used this. it's not necessary in this lib. if provider.date_header in interesting_headers: interesting_headers['date'] = '' # if you're using expires for query string auth, then it trumps date # (and provider.date_header) if expires: interesting_headers['date'] = str(expires) sorted_header_keys = sorted(interesting_headers.keys()) buf = "%s\n" % method for key in sorted_header_keys: val = interesting_headers[key] if key.startswith(provider.header_prefix): buf += "%s:%s\n" % (key, val) else: buf += "%s\n" % val # don't include anything after the first ? in the resource... # unless it is one of the QSA of interest, defined above t = path.split('?') buf += t[0] if len(t) > 1: qsa = t[1].split('&') qsa = [a.split('=', 1) for a in qsa] qsa = [unquote_v(a) for a in qsa if a[0] in qsa_of_interest] if len(qsa) > 0: qsa.sort(key=lambda x: x[0]) qsa = ['='.join(a) for a in qsa] buf += '?' buf += '&'.join(qsa) return buf def merge_meta(headers, metadata, provider=None): if not provider: provider = boto.provider.get_default() metadata_prefix = provider.metadata_prefix final_headers = headers.copy() for k in metadata.keys(): if k.lower() in boto.s3.key.Key.base_user_settable_fields: final_headers[k] = metadata[k] else: final_headers[metadata_prefix + k] = metadata[k] return final_headers def get_aws_metadata(headers, provider=None): if not provider: provider = boto.provider.get_default() metadata_prefix = provider.metadata_prefix metadata = {} for hkey in headers.keys(): if hkey.lower().startswith(metadata_prefix): val = urllib.parse.unquote(headers[hkey]) if isinstance(val, bytes): try: val = val.decode('utf-8') except UnicodeDecodeError: # Just leave the value as-is pass metadata[hkey[len(metadata_prefix):]] = val del headers[hkey] return metadata def retry_url(url, retry_on_404=True, num_retries=10, timeout=None): """ Retry a url. This is specifically used for accessing the metadata service on an instance. Since this address should never be proxied (for security reasons), we create a ProxyHandler with a NULL dictionary to override any proxy settings in the environment. """ for i in range(0, num_retries): try: proxy_handler = urllib.request.ProxyHandler({}) opener = urllib.request.build_opener(proxy_handler) req = urllib.request.Request(url) r = opener.open(req, timeout=timeout) result = r.read() if(not isinstance(result, six.string_types) and hasattr(result, 'decode')): result = result.decode('utf-8') return result except urllib.error.HTTPError as e: code = e.getcode() if code == 404 and not retry_on_404: return '' except Exception as e: boto.log.exception('Caught exception reading instance data') # If not on the last iteration of the loop then sleep. if i + 1 != num_retries: boto.log.debug('Sleeping before retrying') time.sleep(min(2 ** i, boto.config.get('Boto', 'max_retry_delay', 60))) boto.log.error('Unable to read instance data, giving up') return '' def _get_instance_metadata(url, num_retries, timeout=None): return LazyLoadMetadata(url, num_retries, timeout) class LazyLoadMetadata(dict): def __init__(self, url, num_retries, timeout=None): self._url = url self._num_retries = num_retries self._leaves = {} self._dicts = [] self._timeout = timeout data = boto.utils.retry_url(self._url, num_retries=self._num_retries, timeout=self._timeout) if data: fields = data.split('\n') for field in fields: if field.endswith('/'): key = field[0:-1] self._dicts.append(key) else: p = field.find('=') if p > 0: key = field[p + 1:] resource = field[0:p] + '/openssh-key' else: key = resource = field self._leaves[key] = resource self[key] = None def _materialize(self): for key in self: self[key] def __getitem__(self, key): if key not in self: # allow dict to throw the KeyError return super(LazyLoadMetadata, self).__getitem__(key) # already loaded val = super(LazyLoadMetadata, self).__getitem__(key) if val is not None: return val if key in self._leaves: resource = self._leaves[key] last_exception = None for i in range(0, self._num_retries): try: val = boto.utils.retry_url( self._url + urllib.parse.quote(resource, safe="/:"), num_retries=self._num_retries, timeout=self._timeout) if val and val[0] == '{': val = json.loads(val) break else: p = val.find('\n') if p > 0: val = val.split('\n') break except JSONDecodeError as e: boto.log.debug( "encountered '%s' exception: %s" % ( e.__class__.__name__, e)) boto.log.debug( 'corrupted JSON data found: %s' % val) last_exception = e except Exception as e: boto.log.debug("encountered unretryable" + " '%s' exception, re-raising" % ( e.__class__.__name__)) last_exception = e raise boto.log.error("Caught exception reading meta data" + " for the '%s' try" % (i + 1)) if i + 1 != self._num_retries: next_sleep = min( random.random() * 2 ** i, boto.config.get('Boto', 'max_retry_delay', 60)) time.sleep(next_sleep) else: boto.log.error('Unable to read meta data, giving up') boto.log.error( "encountered '%s' exception: %s" % ( last_exception.__class__.__name__, last_exception)) raise last_exception self[key] = val elif key in self._dicts: self[key] = LazyLoadMetadata(self._url + key + '/', self._num_retries) return super(LazyLoadMetadata, self).__getitem__(key) def get(self, key, default=None): try: return self[key] except KeyError: return default def values(self): self._materialize() return super(LazyLoadMetadata, self).values() def items(self): self._materialize() return super(LazyLoadMetadata, self).items() def __str__(self): self._materialize() return super(LazyLoadMetadata, self).__str__() def __repr__(self): self._materialize() return super(LazyLoadMetadata, self).__repr__() def _build_instance_metadata_url(url, version, path): """ Builds an EC2 metadata URL for fetching information about an instance. Example: >>> _build_instance_metadata_url('http://169.254.169.254', 'latest', 'meta-data/') http://169.254.169.254/latest/meta-data/ :type url: string :param url: URL to metadata service, e.g. 'http://169.254.169.254' :type version: string :param version: Version of the metadata to get, e.g. 'latest' :type path: string :param path: Path of the metadata to get, e.g. 'meta-data/'. If a trailing slash is required it must be passed in with the path. :return: The full metadata URL """ return '%s/%s/%s' % (url, version, path) def get_instance_metadata(version='latest', url='http://169.254.169.254', data='meta-data/', timeout=None, num_retries=5): """ Returns the instance metadata as a nested Python dictionary. Simple values (e.g. local_hostname, hostname, etc.) will be stored as string values. Values such as ancestor-ami-ids will be stored in the dict as a list of string values. More complex fields such as public-keys and will be stored as nested dicts. If the timeout is specified, the connection to the specified url will time out after the specified number of seconds. """ try: metadata_url = _build_instance_metadata_url(url, version, data) return _get_instance_metadata(metadata_url, num_retries=num_retries, timeout=timeout) except urllib.error.URLError: boto.log.exception("Exception caught when trying to retrieve " "instance metadata for: %s", data) return None def get_instance_identity(version='latest', url='http://169.254.169.254', timeout=None, num_retries=5): """ Returns the instance identity as a nested Python dictionary. """ iid = {} base_url = _build_instance_metadata_url(url, version, 'dynamic/instance-identity/') try: data = retry_url(base_url, num_retries=num_retries, timeout=timeout) fields = data.split('\n') for field in fields: val = retry_url(base_url + '/' + field + '/', num_retries=num_retries, timeout=timeout) if val[0] == '{': val = json.loads(val) if field: iid[field] = val return iid except urllib.error.URLError: return None def get_instance_userdata(version='latest', sep=None, url='http://169.254.169.254', timeout=None, num_retries=5): ud_url = _build_instance_metadata_url(url, version, 'user-data') user_data = retry_url(ud_url, retry_on_404=False, num_retries=num_retries, timeout=timeout) if user_data: if sep: l = user_data.split(sep) user_data = {} for nvpair in l: t = nvpair.split('=') user_data[t[0].strip()] = t[1].strip() return user_data ISO8601 = '%Y-%m-%dT%H:%M:%SZ' ISO8601_MS = '%Y-%m-%dT%H:%M:%S.%fZ' RFC1123 = '%a, %d %b %Y %H:%M:%S %Z' LOCALE_LOCK = threading.Lock() @contextmanager def setlocale(name): """ A context manager to set the locale in a threadsafe manner. """ with LOCALE_LOCK: saved = locale.setlocale(locale.LC_ALL) try: yield locale.setlocale(locale.LC_ALL, name) finally: locale.setlocale(locale.LC_ALL, saved) def get_ts(ts=None): if not ts: ts = time.gmtime() return time.strftime(ISO8601, ts) def parse_ts(ts): with setlocale('C'): ts = ts.strip() try: dt = datetime.datetime.strptime(ts, ISO8601) return dt except ValueError: try: dt = datetime.datetime.strptime(ts, ISO8601_MS) return dt except ValueError: dt = datetime.datetime.strptime(ts, RFC1123) return dt def find_class(module_name, class_name=None): if class_name: module_name = "%s.%s" % (module_name, class_name) modules = module_name.split('.') c = None try: for m in modules[1:]: if c: c = getattr(c, m) else: c = getattr(__import__(".".join(modules[0:-1])), m) return c except: return None def update_dme(username, password, dme_id, ip_address): """ Update your Dynamic DNS record with DNSMadeEasy.com """ dme_url = 'https://www.dnsmadeeasy.com/servlet/updateip' dme_url += '?username=%s&password=%s&id=%s&ip=%s' s = urllib.request.urlopen(dme_url % (username, password, dme_id, ip_address)) return s.read() def fetch_file(uri, file=None, username=None, password=None): """ Fetch a file based on the URI provided. If you do not pass in a file pointer a tempfile.NamedTemporaryFile, or None if the file could not be retrieved is returned. The URI can be either an HTTP url, or "s3://bucket_name/key_name" """ boto.log.info('Fetching %s' % uri) if file is None: file = tempfile.NamedTemporaryFile() try: if uri.startswith('s3://'): bucket_name, key_name = uri[len('s3://'):].split('/', 1) c = boto.connect_s3(aws_access_key_id=username, aws_secret_access_key=password) bucket = c.get_bucket(bucket_name) key = bucket.get_key(key_name) key.get_contents_to_file(file) else: if username and password: passman = urllib.request.HTTPPasswordMgrWithDefaultRealm() passman.add_password(None, uri, username, password) authhandler = urllib.request.HTTPBasicAuthHandler(passman) opener = urllib.request.build_opener(authhandler) urllib.request.install_opener(opener) s = urllib.request.urlopen(uri) file.write(s.read()) file.seek(0) except: raise boto.log.exception('Problem Retrieving file: %s' % uri) file = None return file class ShellCommand(object): def __init__(self, command, wait=True, fail_fast=False, cwd=None): self.exit_code = 0 self.command = command self.log_fp = StringIO() self.wait = wait self.fail_fast = fail_fast self.run(cwd=cwd) def run(self, cwd=None): boto.log.info('running:%s' % self.command) self.process = subprocess.Popen(self.command, shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=cwd) if(self.wait): while self.process.poll() is None: time.sleep(1) t = self.process.communicate() self.log_fp.write(t[0]) self.log_fp.write(t[1]) boto.log.info(self.log_fp.getvalue()) self.exit_code = self.process.returncode if self.fail_fast and self.exit_code != 0: raise Exception("Command " + self.command + " failed with status " + self.exit_code) return self.exit_code def setReadOnly(self, value): raise AttributeError def getStatus(self): return self.exit_code status = property(getStatus, setReadOnly, None, 'The exit code for the command') def getOutput(self): return self.log_fp.getvalue() output = property(getOutput, setReadOnly, None, 'The STDIN and STDERR output of the command') class AuthSMTPHandler(logging.handlers.SMTPHandler): """ This class extends the SMTPHandler in the standard Python logging module to accept a username and password on the constructor and to then use those credentials to authenticate with the SMTP server. To use this, you could add something like this in your boto config file: [handler_hand07] class=boto.utils.AuthSMTPHandler level=WARN formatter=form07 args=('localhost', 'username', 'password', 'from@abc', ['user1@abc', 'user2@xyz'], 'Logger Subject') """ def __init__(self, mailhost, username, password, fromaddr, toaddrs, subject): """ Initialize the handler. We have extended the constructor to accept a username/password for SMTP authentication. """ super(AuthSMTPHandler, self).__init__(mailhost, fromaddr, toaddrs, subject) self.username = username self.password = password def emit(self, record): """ Emit a record. Format the record and send it to the specified addressees. It would be really nice if I could add authorization to this class without having to resort to cut and paste inheritance but, no. """ try: port = self.mailport if not port: port = smtplib.SMTP_PORT smtp = smtplib.SMTP(self.mailhost, port) smtp.login(self.username, self.password) msg = self.format(record) msg = "From: %s\r\nTo: %s\r\nSubject: %s\r\nDate: %s\r\n\r\n%s" % ( self.fromaddr, ','.join(self.toaddrs), self.getSubject(record), email.utils.formatdate(), msg) smtp.sendmail(self.fromaddr, self.toaddrs, msg) smtp.quit() except (KeyboardInterrupt, SystemExit): raise except: self.handleError(record) class LRUCache(dict): """A dictionary-like object that stores only a certain number of items, and discards its least recently used item when full. >>> cache = LRUCache(3) >>> cache['A'] = 0 >>> cache['B'] = 1 >>> cache['C'] = 2 >>> len(cache) 3 >>> cache['A'] 0 Adding new items to the cache does not increase its size. Instead, the least recently used item is dropped: >>> cache['D'] = 3 >>> len(cache) 3 >>> 'B' in cache False Iterating over the cache returns the keys, starting with the most recently used: >>> for key in cache: ... print key D A C This code is based on the LRUCache class from Genshi which is based on `Myghty `_'s LRUCache from ``myghtyutils.util``, written by Mike Bayer and released under the MIT license (Genshi uses the BSD License). """ class _Item(object): def __init__(self, key, value): self.previous = self.next = None self.key = key self.value = value def __repr__(self): return repr(self.value) def __init__(self, capacity): self._dict = dict() self.capacity = capacity self.head = None self.tail = None def __contains__(self, key): return key in self._dict def __iter__(self): cur = self.head while cur: yield cur.key cur = cur.next def __len__(self): return len(self._dict) def __getitem__(self, key): item = self._dict[key] self._update_item(item) return item.value def __setitem__(self, key, value): item = self._dict.get(key) if item is None: item = self._Item(key, value) self._dict[key] = item self._insert_item(item) else: item.value = value self._update_item(item) self._manage_size() def __repr__(self): return repr(self._dict) def _insert_item(self, item): item.previous = None item.next = self.head if self.head is not None: self.head.previous = item else: self.tail = item self.head = item self._manage_size() def _manage_size(self): while len(self._dict) > self.capacity: del self._dict[self.tail.key] if self.tail != self.head: self.tail = self.tail.previous self.tail.next = None else: self.head = self.tail = None def _update_item(self, item): if self.head == item: return previous = item.previous previous.next = item.next if item.next is not None: item.next.previous = previous else: self.tail = previous item.previous = None item.next = self.head self.head.previous = self.head = item class Password(object): """ Password object that stores itself as hashed. Hash defaults to SHA512 if available, MD5 otherwise. """ hashfunc = _hashfn def __init__(self, str=None, hashfunc=None): """ Load the string from an initial value, this should be the raw hashed password. """ self.str = str if hashfunc: self.hashfunc = hashfunc def set(self, value): if not isinstance(value, bytes): value = value.encode('utf-8') self.str = self.hashfunc(value).hexdigest() def __str__(self): return str(self.str) def __eq__(self, other): if other is None: return False if not isinstance(other, bytes): other = other.encode('utf-8') return str(self.hashfunc(other).hexdigest()) == str(self.str) def __len__(self): if self.str: return len(self.str) else: return 0 def notify(subject, body=None, html_body=None, to_string=None, attachments=None, append_instance_id=True): attachments = attachments or [] if append_instance_id: subject = "[%s] %s" % ( boto.config.get_value("Instance", "instance-id"), subject) if not to_string: to_string = boto.config.get_value('Notification', 'smtp_to', None) if to_string: try: from_string = boto.config.get_value('Notification', 'smtp_from', 'boto') msg = email.mime.multipart.MIMEMultipart() msg['From'] = from_string msg['Reply-To'] = from_string msg['To'] = to_string msg['Date'] = email.utils.formatdate(localtime=True) msg['Subject'] = subject if body: msg.attach(email.mime.text.MIMEText(body)) if html_body: part = email.mime.base.MIMEBase('text', 'html') part.set_payload(html_body) email.encoders.encode_base64(part) msg.attach(part) for part in attachments: msg.attach(part) smtp_host = boto.config.get_value('Notification', 'smtp_host', 'localhost') # Alternate port support if boto.config.get_value("Notification", "smtp_port"): server = smtplib.SMTP(smtp_host, int( boto.config.get_value("Notification", "smtp_port"))) else: server = smtplib.SMTP(smtp_host) # TLS support if boto.config.getbool("Notification", "smtp_tls"): server.ehlo() server.starttls() server.ehlo() smtp_user = boto.config.get_value('Notification', 'smtp_user', '') smtp_pass = boto.config.get_value('Notification', 'smtp_pass', '') if smtp_user: server.login(smtp_user, smtp_pass) server.sendmail(from_string, to_string, msg.as_string()) server.quit() except: boto.log.exception('notify failed') def get_utf8_value(value): if not six.PY2 and isinstance(value, bytes): return value if not isinstance(value, six.string_types): value = six.text_type(value) if isinstance(value, six.text_type): value = value.encode('utf-8') return value def mklist(value): if not isinstance(value, list): if isinstance(value, tuple): value = list(value) else: value = [value] return value def pythonize_name(name): """Convert camel case to a "pythonic" name. Examples:: pythonize_name('CamelCase') -> 'camel_case' pythonize_name('already_pythonized') -> 'already_pythonized' pythonize_name('HTTPRequest') -> 'http_request' pythonize_name('HTTPStatus200Ok') -> 'http_status_200_ok' pythonize_name('UPPER') -> 'upper' pythonize_name('') -> '' """ s1 = _first_cap_regex.sub(r'\1_\2', name) s2 = _number_cap_regex.sub(r'\1_\2', s1) return _end_cap_regex.sub(r'\1_\2', s2).lower() def write_mime_multipart(content, compress=False, deftype='text/plain', delimiter=':'): """Description: :param content: A list of tuples of name-content pairs. This is used instead of a dict to ensure that scripts run in order :type list of tuples: :param compress: Use gzip to compress the scripts, defaults to no compression :type bool: :param deftype: The type that should be assumed if nothing else can be figured out :type str: :param delimiter: mime delimiter :type str: :return: Final mime multipart :rtype: str: """ wrapper = email.mime.multipart.MIMEMultipart() for name, con in content: definite_type = guess_mime_type(con, deftype) maintype, subtype = definite_type.split('/', 1) if maintype == 'text': mime_con = email.mime.text.MIMEText(con, _subtype=subtype) else: mime_con = email.mime.base.MIMEBase(maintype, subtype) mime_con.set_payload(con) # Encode the payload using Base64 email.encoders.encode_base64(mime_con) mime_con.add_header('Content-Disposition', 'attachment', filename=name) wrapper.attach(mime_con) rcontent = wrapper.as_string() if compress: buf = StringIO() gz = gzip.GzipFile(mode='wb', fileobj=buf) try: gz.write(rcontent) finally: gz.close() rcontent = buf.getvalue() return rcontent def guess_mime_type(content, deftype): """Description: Guess the mime type of a block of text :param content: content we're finding the type of :type str: :param deftype: Default mime type :type str: :rtype: : :return: """ # Mappings recognized by cloudinit starts_with_mappings = { '#include': 'text/x-include-url', '#!': 'text/x-shellscript', '#cloud-config': 'text/cloud-config', '#upstart-job': 'text/upstart-job', '#part-handler': 'text/part-handler', '#cloud-boothook': 'text/cloud-boothook' } rtype = deftype for possible_type, mimetype in starts_with_mappings.items(): if content.startswith(possible_type): rtype = mimetype break return(rtype) def compute_md5(fp, buf_size=8192, size=None): """ Compute MD5 hash on passed file and return results in a tuple of values. :type fp: file :param fp: File pointer to the file to MD5 hash. The file pointer will be reset to its current location before the method returns. :type buf_size: integer :param buf_size: Number of bytes per read request. :type size: int :param size: (optional) The Maximum number of bytes to read from the file pointer (fp). This is useful when uploading a file in multiple parts where the file is being split inplace into different parts. Less bytes may be available. :rtype: tuple :return: A tuple containing the hex digest version of the MD5 hash as the first element, the base64 encoded version of the plain digest as the second element and the data size as the third element. """ return compute_hash(fp, buf_size, size, hash_algorithm=md5) def compute_hash(fp, buf_size=8192, size=None, hash_algorithm=md5): hash_obj = hash_algorithm() spos = fp.tell() if size and size < buf_size: s = fp.read(size) else: s = fp.read(buf_size) while s: if not isinstance(s, bytes): s = s.encode('utf-8') hash_obj.update(s) if size: size -= len(s) if size <= 0: break if size and size < buf_size: s = fp.read(size) else: s = fp.read(buf_size) hex_digest = hash_obj.hexdigest() base64_digest = encodebytes(hash_obj.digest()).decode('utf-8') if base64_digest[-1] == '\n': base64_digest = base64_digest[0:-1] # data_size based on bytes read. data_size = fp.tell() - spos fp.seek(spos) return (hex_digest, base64_digest, data_size) def find_matching_headers(name, headers): """ Takes a specific header name and a dict of headers {"name": "value"}. Returns a list of matching header names, case-insensitive. """ return [h for h in headers if h.lower() == name.lower()] def merge_headers_by_name(name, headers): """ Takes a specific header name and a dict of headers {"name": "value"}. Returns a string of all header values, comma-separated, that match the input header name, case-insensitive. """ matching_headers = find_matching_headers(name, headers) return ','.join(str(headers[h]) for h in matching_headers if headers[h] is not None) class RequestHook(object): """ This can be extended and supplied to the connection object to gain access to request and response object after the request completes. One use for this would be to implement some specific request logging. """ def handle_request_data(self, request, response, error=False): pass def host_is_ipv6(hostname): """ Detect (naively) if the hostname is an IPV6 host. Return a boolean. """ # empty strings or anything that is not a string is automatically not an # IPV6 address if not hostname or not isinstance(hostname, str): return False if hostname.startswith('['): return True if len(hostname.split(':')) > 2: return True # Anything else that doesn't start with brackets or doesn't have more than # one ':' should not be an IPV6 address. This is very naive but the rest of # the connection chain should error accordingly for typos or ill formed # addresses return False def parse_host(hostname): """ Given a hostname that may have a port name, ensure that the port is trimmed returning only the host, including hostnames that are IPV6 and may include brackets. """ # ensure that hostname does not have any whitespaces hostname = hostname.strip() if host_is_ipv6(hostname): return hostname.split(']:', 1)[0].strip('[]') else: return hostname.split(':', 1)[0]