[feat] Support network cache in Download.download()

src/zc/buildout/buildout.py

@@ -324,6 +324,9 @@ def _get_user_config():
     return os.path.join(buildout_home, 'default.cfg')
 
 
+network_cache_parameter_dict = {}
+
+
 @commands
 class Buildout(DictMixin):
 
@@ -576,6 +579,31 @@ class Buildout(DictMixin):
 
         os.chdir(options['directory'])
 
+        networkcache_section_name = options.get('networkcache-section')
+        if networkcache_section_name:
+            networkcache_section = self[networkcache_section_name]
+            for k in (
+                'download-cache-url',
+                'download-dir-url',
+                'upload-cache-url',
+                'upload-dir-url',
+                'signature-certificate-list',
+                'signature-private-key-file',
+                'shacache-ca-file',
+                'shacache-cert-file',
+                'shacache-key-file',
+                'shadir-ca-file',
+                'shadir-cert-file',
+                'shadir-key-file',
+            ):
+                network_cache_parameter_dict[k] = networkcache_section.get(k, '')
+                # parse signature list
+                cert_marker = '-----BEGIN CERTIFICATE-----'
+            network_cache_parameter_dict['signature-certificate-list'] = \
+                [cert_marker + '\n' + q.strip() \
+                    for q in network_cache_parameter_dict['signature-certificate-list'].split(cert_marker) \
+                    if q.strip()]
+
     def _buildout_path(self, name):
         if '${' in name:
             return name

src/zc/buildout/download.py

@@ -199,10 +199,29 @@ class Download(object):
         handle, tmp_path = tempfile.mkstemp(prefix='buildout-')
         os.close(handle)
         try:
-            tmp_path, headers = urlretrieve(url, tmp_path)
-            if not check_md5sum(tmp_path, md5sum):
-                raise ChecksumError(
-                    'MD5 checksum mismatch downloading %r' % url)
+            from .buildout import network_cache_parameter_dict as nc
+            if not download_network_cached(
+                nc.get('download-dir-url'),
+                nc.get('download-cache-url'),
+                tmp_path, url, self.logger,
+                nc.get('signature-certificate-list'), md5sum):
+                # Download from original url if not cached or md5sum doesn't match.
+                tmp_path, headers = urlretrieve(url, tmp_path)
+                if not check_md5sum(tmp_path, md5sum):
+                    raise ChecksumError(
+                        'MD5 checksum mismatch downloading %r' % url)
+                # Upload the file to network cache.
+                if nc.get('upload-cache-url') and nc.get('upload-dir-url'):
+                    upload_network_cached(
+                        nc.get('upload-dir-url'),
+                        nc.get('upload-cache-url'), url, tmp_path, self.logger,
+                        nc.get('signature-private-key-file'),
+                        nc.get('shacache-ca-file'),
+                        nc.get('shacache-cert-file'),
+                        nc.get('shacache-key-file'),
+                        nc.get('shadir-ca-file'),
+                        nc.get('shadir-cert-file'),
+                        nc.get('shadir-key-file'))
         except IOError:
             e = sys.exc_info()[1]
             os.remove(tmp_path)
@@ -271,6 +290,8 @@ def remove(path):
     if os.path.exists(path):
         os.remove(path)
 
+from zc.buildout.networkcache import download_network_cached, \
+                                     upload_network_cached
 
 def locate_at(source, dest):
     if dest is None or realpath(dest) == realpath(source):