# coding=utf-8
"""
Download mode implementation.
"""
from __future__ import division
import os
import re
import sys
import errno
import mimetypes
import threading
from time import sleep, time
from mailbox import Message
from httpie.output.streams import RawStream
from httpie.models import HTTPResponse
from httpie.utils import humanize_bytes
from httpie.compat import urlsplit
PARTIAL_CONTENT = 206
CLEAR_LINE = '\r\033[K'
PROGRESS = (
'{percentage: 6.2f} %'
' {downloaded: >10}'
' {speed: >10}/s'
' {eta: >8} ETA'
)
PROGRESS_NO_CONTENT_LENGTH = '{downloaded: >10} {speed: >10}/s'
SUMMARY = 'Done. {downloaded} in {time:0.5f}s ({speed}/s)\n'
SPINNER = '|/-\\'
class ContentRangeError(ValueError):
pass
def parse_content_range(content_range, resumed_from):
"""
Parse and validate Content-Range header.
<http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html>
:param content_range: the value of a Content-Range response header
eg. "bytes 21010-47021/47022"
:param resumed_from: first byte pos. from the Range request header
:return: total size of the response body when fully downloaded.
"""
if content_range is None:
raise ContentRangeError('Missing Content-Range')
pattern = (
'^bytes (?P<first_byte_pos>\d+)-(?P<last_byte_pos>\d+)'
'/(\*|(?P<instance_length>\d+))$'
)
match = re.match(pattern, content_range)
if not match:
raise ContentRangeError(
'Invalid Content-Range format %r' % content_range)
content_range_dict = match.groupdict()
first_byte_pos = int(content_range_dict['first_byte_pos'])
last_byte_pos = int(content_range_dict['last_byte_pos'])
instance_length = (
int(content_range_dict['instance_length'])
if content_range_dict['instance_length']
else None
)
# "A byte-content-range-spec with a byte-range-resp-spec whose
# last- byte-pos value is less than its first-byte-pos value,
# or whose instance-length value is less than or equal to its
# last-byte-pos value, is invalid. The recipient of an invalid
# byte-content-range- spec MUST ignore it and any content
# transferred along with it."
if (first_byte_pos >= last_byte_pos or
(instance_length is not None and
instance_length <= last_byte_pos)):
raise ContentRangeError(
'Invalid Content-Range returned: %r' % content_range)
if (first_byte_pos != resumed_from or
(instance_length is not None and
last_byte_pos + 1 != instance_length)):
# Not what we asked for.
raise ContentRangeError(
'Unexpected Content-Range returned (%r)'
' for the requested Range ("bytes=%d-")'
% (content_range, resumed_from)
)
return last_byte_pos + 1
def filename_from_content_disposition(content_disposition):
"""
Extract and validate filename from a Content-Disposition header.
:param content_disposition: Content-Disposition value
:return: the filename if present and valid, otherwise `None`
"""
# attachment; filename=jkbrzt-httpie-0.4.1-20-g40bd8f6.tar.gz
msg = Message('Content-Disposition: %s' % content_disposition)
filename = msg.get_filename()
if filename:
# Basic sanitation.
filename = os.path.basename(filename).lstrip('.').strip()
if filename:
return filename
def filename_from_url(url, content_type):
fn = urlsplit(url).path.rstrip('/')
fn = os.path.basename(fn) if fn else 'index'
if '.' not in fn and content_type:
content_type = content_type.split(';')[0]
if content_type == 'text/plain':
# mimetypes returns '.ksh'
ext = '.txt'
else:
ext = mimetypes.guess_extension(content_type)
if ext == '.htm': # Python 3
ext = '.html'
if ext:
fn += ext
return fn
def trim_filename(filename, max_len):
if len(filename) > max_len:
trim_by = len(filename) - max_len
name, ext = os.path.splitext(filename)
if trim_by >= len(name):
filename = filename[:-trim_by]
else:
filename = name[:-trim_by] + ext
return filename
def get_filename_max_length(directory):
max_len = 255
try:
pathconf = os.pathconf
except AttributeError:
pass # non-posix
else:
try:
max_len = pathconf(directory, 'PC_NAME_MAX')
except OSError as e:
if e.errno != errno.EINVAL:
raise
return max_len
def trim_filename_if_needed(filename, directory='.', extra=0):
max_len = get_filename_max_length(directory) - extra
if len(filename) > max_len:
filename = trim_filename(filename, max_len)
return filename
def get_unique_filename(filename, exists=os.path.exists):
attempt = 0
while True:
suffix = '-' + str(attempt) if attempt > 0 else ''
try_filename = trim_filename_if_needed(filename, extra=len(suffix))
try_filename += suffix
if not exists(try_filename):
return try_filename
attempt += 1
class Downloader(object):
def __init__(self, output_file=None,
resume=False, progress_file=sys.stderr):
"""
:param resume: Should the download resume if partial download
already exists.
:type resume: bool
:param output_file: The file to store response body in. If not
provided, it will be guessed from the response.
:param progress_file: Where to report download progress.
"""
self._output_file = output_file
self._resume = resume
self._resumed_from = 0
self.finished = False
self.status = Status()
self._progress_reporter = ProgressReporterThread(
status=self.status,
output=progress_file
)
def pre_request(self, request_headers):
"""Called just before the HTTP request is sent.
Might alter `request_headers`.
:type request_headers: dict
"""
# Ask the server not to encode the content so that we can resume, etc.
request_headers['Accept-Encoding'] = 'identity'
if self._resume:
bytes_have = os.path.getsize(self._output_file.name)
if bytes_have:
# Set ``Range`` header to resume the download
# TODO: Use "If-Range: mtime" to make sure it's fresh?
request_headers['Range'] = 'bytes=%d-' % bytes_have
self._resumed_from = bytes_have
def start(self, response):
"""
Initiate and return a stream for `response` body with progress
callback attached. Can be called only once.
:param response: Initiated response object with headers already fetched
:type response: requests.models.Response
:return: RawStream, output_file
"""
assert not self.status.time_started
# FIXME: some servers still might sent Content-Encoding: gzip
# <https://github.com/jkbrzt/httpie/issues/423>
try:
total_size = int(response.headers['Content-Length'])
except (KeyError, ValueError, TypeError):
total_size = None
if self._output_file:
if self._resume and response.status_code == PARTIAL_CONTENT:
total_size = parse_content_range(
response.headers.get('Content-Range'),
self._resumed_from
)
else:
self._resumed_from = 0
try:
self._output_file.seek(0)
self._output_file.truncate()
except IOError:
pass # stdout
else:
# TODO: Should the filename be taken from response.history[0].url?
# Output file not specified. Pick a name that doesn't exist yet.
filename = None
if 'Content-Disposition' in response.headers:
filename = filename_from_content_disposition(
response.headers['Content-Disposition'])
if not filename:
filename = filename_from_url(
url=response.url,
content_type=response.headers.get('Content-Type'),
)
self._output_file = open(get_unique_filename(filename), mode='a+b')
self.status.started(
resumed_from=self._resumed_from,
total_size=total_size
)
stream = RawStream(
msg=HTTPResponse(response),
with_headers=False,
with_body=True,
on_body_chunk_downloaded=self.chunk_downloaded,
chunk_size=1024 * 8
)
self._progress_reporter.output.write(
'Downloading %sto "%s"\n' % (
(humanize_bytes(total_size) + ' '
if total_size is not None
else ''),
self._output_file.name
)
)
self._progress_reporter.start()
return stream, self._output_file
def finish(self):
assert not self.finished
self.finished = True
self.status.finished()
def failed(self):
self._progress_reporter.stop()
@property
def interrupted(self):
return (
self.finished and
self.status.total_size and
self.status.total_size != self.status.downloaded
)
def chunk_downloaded(self, chunk):
"""
A download progress callback.
:param chunk: A chunk of response body data that has just
been downloaded and written to the output.
:type chunk: bytes
"""
self.status.chunk_downloaded(len(chunk))
class Status(object):
"""Holds details about the downland status."""
def __init__(self):
self.downloaded = 0
self.total_size = None
self.resumed_from = 0
self.time_started = None
self.time_finished = None
def started(self, resumed_from=0, total_size=None):
assert self.time_started is None
self.total_size = total_size
self.downloaded = self.resumed_from = resumed_from
self.time_started = time()
def chunk_downloaded(self, size):
assert self.time_finished is None
self.downloaded += size
@property
def has_finished(self):
return self.time_finished is not None
def finished(self):
assert self.time_started is not None
assert self.time_finished is None
self.time_finished = time()
class ProgressReporterThread(threading.Thread):
"""
Reports download progress based on its status.
Uses threading to periodically update the status (speed, ETA, etc.).
"""
def __init__(self, status, output, tick=.1, update_interval=1):
"""
:type status: Status
:type output: file
"""
super(ProgressReporterThread, self).__init__()
self.status = status
self.output = output
self._tick = tick
self._update_interval = update_interval
self._spinner_pos = 0
self._status_line = ''
self._prev_bytes = 0
self._prev_time = time()
self._should_stop = threading.Event()
def stop(self):
"""Stop reporting on next tick."""
self._should_stop.set()
def run(self):
while not self._should_stop.is_set():
if self.status.has_finished:
self.sum_up()
break
self.report_speed()
sleep(self._tick)
def report_speed(self):
now = time()
if now - self._prev_time >= self._update_interval:
downloaded = self.status.downloaded
try:
speed = ((downloaded - self._prev_bytes) /
(now - self._prev_time))
except ZeroDivisionError:
speed = 0
if not self.status.total_size:
self._status_line = PROGRESS_NO_CONTENT_LENGTH.format(
downloaded=humanize_bytes(downloaded),
speed=humanize_bytes(speed),
)
else:
try:
percentage = downloaded / self.status.total_size * 100
except ZeroDivisionError:
percentage = 0
if not speed:
eta = '-:--:--'
else:
s = int((self.status.total_size - downloaded) / speed)
h, s = divmod(s, 60 * 60)
m, s = divmod(s, 60)
eta = '{0}:{1:0>2}:{2:0>2}'.format(h, m, s)
self._status_line = PROGRESS.format(
percentage=percentage,
downloaded=humanize_bytes(downloaded),
speed=humanize_bytes(speed),
eta=eta,
)
self._prev_time = now
self._prev_bytes = downloaded
self.output.write(
CLEAR_LINE +
' ' +
SPINNER[self._spinner_pos] +
' ' +
self._status_line
)
self.output.flush()
self._spinner_pos = (self._spinner_pos + 1
if self._spinner_pos + 1 != len(SPINNER)
else 0)
def sum_up(self):
actually_downloaded = (
self.status.downloaded - self.status.resumed_from)
time_taken = self.status.time_finished - self.status.time_started
self.output.write(CLEAR_LINE)
try:
speed = actually_downloaded / time_taken
except ZeroDivisionError:
# Either time is 0 (not all systems provide `time.time`
# with a better precision than 1 second), and/or nothing
# has been downloaded.
speed = actually_downloaded
self.output.write(SUMMARY.format(
downloaded=humanize_bytes(actually_downloaded),
total=(self.status.total_size and
humanize_bytes(self.status.total_size)),
speed=humanize_bytes(speed),
time=time_taken,
))
self.output.flush()