# coding=utf-8 """ Download mode implementation. """ from __future__ import division import os import re import sys 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. :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\d+)-(?P\d+)' '/(\*|(?P\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 get_unique_filename(filename, exists=os.path.exists): attempt = 0 while True: suffix = '-' + str(attempt) if attempt > 0 else '' if not exists(filename + suffix): return filename + suffix attempt += 1 class Download(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 """ # Disable content encoding so that we can resume, etc. request_headers['Accept-Encoding'] = None 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 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 if total_size is not 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()