Updated sleep_interval to allow random range.

Updated sleep_interval flag to allow range from which we derive a random
timer for the sleep period.

youtube_dl/YoutubeDL.py

@@ -249,6 +249,7 @@ class YoutubeDL(object):
     call_home:         Boolean, true iff we are allowed to contact the
                        youtube-dl servers for debugging.
     sleep_interval:    Number of seconds to sleep before each download.
+                       Can accept range for random sleep in form a-b.
     listformats:       Print an overview of available video formats and exit.
     list_thumbnails:   Print a table of all thumbnails and exit.
     match_filter:      A function that gets called with the info_dict of

youtube_dl/downloader/common.py

@@ -4,6 +4,7 @@ import os
 import re
 import sys
 import time
+import random
 
 from ..compat import compat_os_name
 from ..utils import (
@@ -343,6 +344,12 @@ class FileDownloader(object):
             return True
 
         sleep_interval = self.params.get('sleep_interval')
+        if '-' in sleep_interval:
+            try:
+                start, stop = sleep_interval.split('-')
+                sleep_interval = random.randrange(int(start), int(stop))
+            except ValueError:
+                raise ValueError("Invalid range 'a-b' provided, expected 'a' to be integer less than 'b'")
         if sleep_interval:
             self.to_screen('[download] Sleeping %s seconds...' % sleep_interval)
             time.sleep(sleep_interval)

youtube_dl/options.py

@@ -480,7 +480,7 @@ def parseOpts(overrideArguments=None):
         help='Work around terminals that lack bidirectional text support. Requires bidiv or fribidi executable in PATH')
     workarounds.add_option(
         '--sleep-interval', metavar='SECONDS',
-        dest='sleep_interval', type=float,
+        dest='sleep_interval',
         help='Number of seconds to sleep before each download.')
 
     verbosity = optparse.OptionGroup(parser, 'Verbosity / Simulation Options')