[lnst] ResourceCache: Adding a cache for modules and tools

commit a77f43452f69d9cf9d5ce295be076eff3812084c Author: Radek Pazdera <rpazdera(a)redhat.com&gt; Date: Thu Nov 8 16:17:47 2012 +0100 ResourceCache: Adding a cache for modules and tools This commit introduces resource cache for managing test modules and tools that are transfered from controller to the slaves. Signed-off-by: Radek Pazdera <rpazdera(a)redhat.com&gt; Common/ResourceCache.py | 132 +++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 132 insertions(+), 0 deletions(-) --- diff --git a/Common/ResourceCache.py b/Common/ResourceCache.py new file mode 100644 index 0000000..9bc463f --- /dev/null +++ b/Common/ResourceCache.py @@ -0,0 +1,132 @@ +""" + +Copyright 2012 Red Hat, Inc. +Licensed under the GNU General Public License, version 2 as +published by the Free Software Foundation; see COPYING for details. +""" + +__author__ = """ +rpazdera(a)redhat.com (Radek Pazdera) +""" + +import logging +import os +import re +import time +import shutil +from Common.Utils import md5sum +from Common.ExecCmd import exec_cmd + +class ResourceCacheError(Exception): + pass + +class ResourceCache(object): + _CACHE_INDEX_FILE_NAME = "index" + _root = None + _entries = {} + _expiration_period = None + + def __init__(self, cache_path, expiration_period): + if os.path.exists(cache_path): + if os.path.isdir(cache_path): + self._root = cache_path + else: + raise ResourceCacheError("Invalid cache path (%s)" % cache_path) + else: + os.mkdir(cache_path) + self._root = cache_path + + self._read_index() + self._expiration_period = expiration_period + + def _read_index(self): + logging.debug("Test cache index loaded") + try: + f = open(self._get_index_loc(), "r") + except: + return + + for line in f.readlines(): + if not re.match("^\s*#", line) and not re.match("^\s*$", line): + try: + entry_hash, last_used, entry_type, \ + entry_name, entry_path = line.split() + except: + raise ResourceCacheError("Malformed cache index") + + entry = {"type": entry_type, "name": entry_name, + "last_used": int(last_used), "path": entry_path } + self._entries[entry_hash] = entry + + def _save_index(self): + logging.debug("Test cache index commited") + with open(self._get_index_loc(), "w") as f: + header = "# hash " \ + "last_used type name path\n" + f.write(header) + for entry_hash, entry in self._entries.iteritems(): + values = (entry_hash, entry["last_used"], entry["type"], + entry["name"], entry["path"]) + line = "%s %d %s %s %s\n" % values + f.write(line) + + def _get_index_loc(self): + return "%s/%s" % (self._root, self._CACHE_INDEX_FILE_NAME) + + def query(self, res_hash): + return res_hash in self._entries + + def get_path(self, res_hash): + return "%s/%s" % (self._root, self._entries[res_hash]["path"]) + + def renew_entry(self, entry_hash): + self._entries[entry_hash]["last_used"] = int(time.time()) + self._save_index() + + def add_cache_entry(self, entry_hash, filepath, entry_name, entry_type): + if entry_hash in self._entries: + raise ResourceCacheError("File already in cache") + + entry_dir = "%s/%s" % (self._root, entry_hash) + os.mkdir(entry_dir) + + shutil.move(filepath, entry_dir) + entry_path = "%s/%s" % (entry_dir, os.path.basename(filepath)) + + if entry_type == "module": + filename = "Test%s.py" % entry_name + shutil.move(entry_path, "%s/%s" % (entry_dir, filename)) + elif entry_type == "tools": + filename = entry_name + tools_dir = "%s/%s" % (entry_dir, filename) + + exec_cmd("tar xjmf \"%s\" -C \"%s\"" % (entry_path, entry_dir)) + exec_cmd("cd \"%s\" && ./lnst-setup.sh" % tools_dir) + + entry = {"type": entry_type, "name": entry_name, + "last_used": int(time.time()), + "path": "%s/%s" % (entry_hash, filename)} + self._entries[entry_hash] = entry + + self._save_index() + + return entry_hash + + def del_cache_entry(self, entry_hash): + if entry_hash in self._entries: + shutil.rmtree("%s/%s" % (self._root, entry_hash)) + del self._entries[entry_hash] + self._save_index() + + def del_old_entries(self): + if self._expiration_period == 0: + return + + rm = [] + now = time.time() + for entry_hash, entry in self._entries.iteritems(): + if entry["last_used"] <= (now - self._expiration_period): + rm.append(entry_hash) + + for entry_hash in rm: + self.del_cache_entry(entry_hash)