Revert "Support network cache in zc.buildout.easy_install."

This reverts commit e6e348fa.

src/zc/buildout/easy_install.py

@@ -48,22 +48,6 @@ _oprp = getattr(os.path, 'realpath', lambda path: path)
 def realpath(path):
     return os.path.normcase(os.path.abspath(_oprp(path)))
 
-from zc.buildout.networkcache import get_filename_from_url, \
-     download_network_cached, \
-     upload_network_cached, \
-     download_index_network_cached, \
-     upload_index_network_cached
-from setuptools.package_index import HREF, URL_SCHEME, \
-     distros_for_url, htmldecode
-try:
-    # Python 3
-    from urllib.error import HTTPError
-    from urllib.parse import urljoin
-except ImportError:
-    # Python 2
-    from urllib2 import HTTPError
-    from urlparse import urljoin
-
 default_index_url = os.environ.get(
     'BUILDOUT_TESTING_INDEX_URL',
     'https://pypi.org/simple',
@@ -148,96 +132,6 @@ class AllowHostsPackageIndex(setuptools.package_index.PackageIndex):
             return setuptools.package_index.PackageIndex.url_ok(
                                                 self, url, False)
 
-    def obtain(self, requirement, installer=None):
-        self._current_requirement = str(requirement)
-        return super(AllowHostsPackageIndex, self).obtain(requirement, installer)
-
-    def find_packages(self, requirement):
-        self._current_requirement = str(requirement)
-        return super(AllowHostsPackageIndex, self).find_packages(requirement)
-
-    def process_url(self, url, retrieve=False):
-        """Evaluate a URL as a possible download, and maybe retrieve it"""
-        if url in self.scanned_urls and not retrieve:
-            return
-        self.scanned_urls[url] = True
-        if not URL_SCHEME(url):
-            self.process_filename(url)
-            return
-        else:
-            dists = list(distros_for_url(url))
-            if dists:
-                if not self.url_ok(url):
-                    return
-                self.debug("Found link: %s", url)
-
-        if dists or not retrieve or url in self.fetched_urls:
-            list(map(self.add, dists))
-            return  # don't need the actual page
-
-        if not self.url_ok(url):
-            self.fetched_urls[url] = True
-            return
-
-        self.info("Reading %s", url)
-        self.fetched_urls[url] = True   # prevent multiple fetch attempts
-
-        # We download from cache only if we have a specific version for egg requirement
-        # Reason: If no specific version, we don't want to be blocked with an old index.
-        #         If there is specific version, we want index to freeze forever.
-        download_result = False
-        requirement = getattr(self, '_current_requirement', '')
-        from .buildout import network_cache_parameter_dict as nc
-        if '==' in requirement:
-            download_result = download_index_network_cached(
-                nc.get('download-dir-url'),
-                nc.get('download-cache-url'),
-                url, requirement, logger,
-                nc.get('signature-certificate-list'))
-        if download_result:
-            # Successfully fetched from cache. Hardcode some things...
-            page, base = download_result
-            f = None
-            self.fetched_urls[base] = True
-        else:
-            f = self.open_url(url, "Download error on %s: %%s -- Some packages may not be found!" % url)
-            if f is None: return
-            self.fetched_urls[f.url] = True
-            if 'html' not in f.headers.get('content-type', '').lower():
-                f.close()   # not html, we can't process it
-                return
-
-            base = f.url     # handle redirects
-            page = f.read()
-            if not isinstance(page, str): # We are in Python 3 and got bytes. We want str.
-                if isinstance(f, HTTPError):
-                    # Errors have no charset, assume latin1:
-                    charset = 'latin-1'
-                else:
-                    charset = f.headers.get_param('charset') or 'latin-1'
-                page = page.decode(charset, "ignore")
-            f.close()
-            # Upload the index to network cache.
-            if (nc.get('upload-cache-url')
-                and nc.get('upload-dir-url')
-                and '==' in requirement
-                and 200 <= getattr(f, 'code', 0) < 300):
-                upload_index_network_cached(
-                    nc.get('upload-dir-url'),
-                    nc.get('upload-cache-url'),
-                    url, base, requirement, page, 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'))
-        for match in HREF.finditer(page):
-            link = urljoin(base, htmldecode(match.group(1)))
-            self.process_url(link)
-        if url.startswith(self.index_url) and getattr(f,'code',None)!=404:
-            page = self.process_index(url, page)
 
 _indexes = {}
 def _get_index(index_url, find_links, allow_hosts=('*',)):
@@ -615,36 +509,7 @@ class Installer:
             ):
             return dist
 
-        # Try to download from shacache first. If not possible, downloads from
-        # Original location and uploads it to shacache.
-        filename = get_filename_from_url(dist.location)
-        new_location = os.path.join(tmp, filename)
-        downloaded_from_cache = False
-        from .buildout import network_cache_parameter_dict as nc
-        if nc.get('download-dir-url') \
-            and nc.get('download-dir-url') \
-            and nc.get('signature-certificate-list'):
-            downloaded_from_cache = download_network_cached(
-                nc.get('download-dir-url'),
-                nc.get('download-cache-url'),
-                new_location, dist.location, logger,
-                nc.get('signature-certificate-list'))
-        if not downloaded_from_cache:
-            new_location = self._index.download(dist.location, tmp)
-            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'),
-                    dist.location, new_location, 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'))
-
+        new_location = self._index.download(dist.location, tmp)
         if (download_cache
             and (realpath(new_location) == realpath(dist.location))
             and os.path.isfile(new_location)