Use thread pool for faster network IO

pypiup/requirements.py

@@ -1,6 +1,8 @@
 # -*- coding: utf-8 -*-
 from __future__ import unicode_literals
 
+from multiprocessing.dummy import Pool as ThreadPool
+
 import click
 from pypiup.requirement import Requirement
 
@@ -22,17 +24,24 @@ def read_file(self, requirements_filename):
         try:
             requirements_file = open(requirements_filename)
             requirements_file_lines = requirements_file.read().splitlines()
+            pool = ThreadPool()
+            lines = [
+                line for line in requirements_file_lines
+                if not self.should_ignore_requirement(line)
+            ]
             with click.progressbar(
-                    iterable=requirements_file_lines,
+                    length=len(lines),
                     label='Getting requirements details',
                     bar_template='%(label)s %(bar)s | %(info)s',
                     fill_char=click.style(u'█', fg='cyan'),
                     empty_char=' ') as bar:
-                requirements = []
-                for line in bar:
-                    if not self.should_ignore_requirement(line):
-                        requirement = Requirement(line)
-                        requirements.append(requirement)
+                # Apply decorator
+                req_with_upd = barupdate(bar)(Requirement)
+                requirements = pool.map(req_with_upd, lines)
+                # cleanup and wait for work to finish
+                pool.close()
+                pool.join()
+
                 self.requirements = requirements
                 self.show_details()
                 self.show_stats()
@@ -69,3 +78,16 @@ def show_stats(self):
         click.echo("  Update available: %s" % stat_needs_update)
         click.echo("  Invalid Semver: %s" % stat_invalid_semver)
         click.echo("  Non PyPI Requirements: %s" % stat_invalid)
+
+
+def barupdate(bar_obj, size=1):
+    """Decorator for updating progressbar after
+    object instantiation complete.
+    """
+    def decorator(cls):
+        def inner(*args, **kwargs):
+            instance = cls(*args, **kwargs)
+            bar_obj.update(size)
+            return instance
+        return inner
+    return decorator