#!/usr/bin/env python # Licensed to Cloudera, Inc. under one # or more contributor license agreements. See the NOTICE file # distributed with this work for additional information # regarding copyright ownership. Cloudera, Inc. licenses this file # to you under the Apache License, Version 2.0 (the # "License"); you may not use this file except in compliance # with the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """ Registry for the applications """ from builtins import object import glob import logging import os import sys import json import common from common import cmp if sys.version_info[0] > 2: from builtins import object LOG = logging.getLogger(__name__) class AppRegistry(object): """ Represents a registry. """ def __init__(self): """Open the existing registry""" self._reg_path = os.path.join(common.HUE_APP_REG_DIR, 'app.reg') self._initialized = False self._apps = { } # Map of name -> HueApp self._open() def _open(self): """Open the registry file. May raise OSError""" if os.path.exists(self._reg_path): if sys.version_info[0] > 2: reg_file = open(self._reg_path) else: reg_file = file(self._reg_path) app_list = json.load(reg_file) reg_file.close() for app_json in app_list: app_json.setdefault('author', 'Unknown') # Added after 0.9 app = HueApp.create(app_json) self._apps[app.name] = app self._initialized = True def _write(self, path): """Write out the registry to the given path""" if sys.version_info[0] > 2: outfile = open(path, 'w') else: outfile = file(path, 'w') json.dump(list(self._apps.values()), outfile, cls=AppJsonEncoder, indent=2) outfile.close() def contains(self, app): """Returns whether the app (of the same version) is in the registry""" try: existing = self._apps[app.name] return existing.version == app.version except KeyError: return False def register(self, app): """register(app) -> True/False""" assert self._initialized, "Registry not yet initialized" try: existing = self._apps[app.name] version_diff = common.cmp_version(existing.version, app.version) if version_diff == 0: LOG.warn('%s is already registered' % (app,)) return False elif version_diff < 0: LOG.info('Upgrading %s from version %s' % (app, existing.version)) elif version_diff > 0: LOG.error('A newer version (%s) of %s is already installed' % (existing.version, app)) return False except KeyError: pass LOG.info('Updating registry with %s' % (app,)) self._apps[app.name] = app return True def unregister(self, app_name): """unregister(app_Name) -> HueApp. May raise KeyError""" assert self._initialized, "Registry not yet initialized" app = self._apps[app_name] del self._apps[app_name] return app def get_all_apps(self): """get_all_apps() -> List of HueApp""" return list(self._apps.values()) def save(self): """Save and write out the registry""" assert self._initialized, "Registry not yet initialized" self._write(self._reg_path) LOG.info('=== Saved registry at %s' % (self._reg_path,)) class HueApp(object): """ Represents an app. Path provided should be absolute or relative to common.APPS_ROOT """ @staticmethod def create(json): return HueApp(json['name'], json['version'], json['path'], json['desc'], json['author']) def __init__(self, name, version, path, desc, author): self.name = name self.version = version self.path = path self.desc = desc self.author = author def __str__(self): return "%s v.%s" % (self.name, self.version) def __cmp__(self, other): if not isinstance(other, HueApp): raise TypeError return cmp((self.name, self.version), (other.name, other.version)) @property def rel_path(self): if os.path.isabs(self.path): return os.path.relpath(self.path, common.APPS_ROOT) else: return self.path @property def abs_path(self): if not os.path.isabs(self.path): return os.path.abspath(os.path.join(common.APPS_ROOT, self.path)) else: return self.path def use_rel_path(self): self.path = self.rel_path def use_abs_path(self): self.path = self.abs_path def jsonable(self): return dict(name=self.name, version=self.version, path=self.path, desc=self.desc, author=self.author) def find_ext_pys(self): """find_ext_pys() -> A list of paths for all ext-py packages""" return glob.glob(os.path.join(self.abs_path, 'ext-py', '*')) def get_conffiles(self): """get_conffiles() -> A list of config (.ini) files""" return glob.glob(os.path.join(self.abs_path, 'conf', '*.ini')) def install_conf(self): """ install_conf() -> True/False Symlink the app's conf/*.ini files into the conf directory. """ installed = [ ] for target in self.get_conffiles(): link_name = os.path.join(common.HUE_CONF_DIR, os.path.basename(target)) # Does the link already exists? if os.path.islink(link_name): try: cur = os.readlink(link_name) if cur == target: LOG.warn("Symlink for configuration already exists: %s" % (link_name,)) installed.append(link_name) continue # Remove broken link if not os.path.exists(cur): os.unlink(link_name) LOG.warn("Removing broken link: %s" % (link_name,)) except OSError as ex: LOG.warn("Error checking for existing link %s: %s" % (link_name, ex)) # Actually install the link try: os.symlink(target, link_name) LOG.info('Symlink config %s -> %s' % (link_name, target)) installed.append(link_name) except OSError as ex: LOG.error("Failed to symlink %s to %s: %s" % (target, link_name, ex)) for lnk in installed: try: os.unlink(lnk) except OSError as ex2: LOG.error("Failed to cleanup link %s: %s" % (link_name, ex2)) return False return True def uninstall_conf(self): """uninstall_conf() -> True/False""" app_conf_dir = os.path.abspath(os.path.join(self.abs_path, 'conf')) if not os.path.isdir(app_conf_dir): return True # Check all symlink in the conf dir and remove any that point to this app for name in os.listdir(common.HUE_CONF_DIR): path = os.path.join(common.HUE_CONF_DIR, name) if not os.path.islink(path): continue target = os.readlink(path) target_dir = os.path.abspath(os.path.dirname(target)) if target_dir == app_conf_dir: try: os.unlink(path) LOG.info('Remove config symlink %s -> %s' % (path, target)) except OSError as ex: LOG.error("Failed to remove configuration link %s: %s" % (path, ex)) return False return True class AppJsonEncoder(json.JSONEncoder): def __init__(self, **kwargs): json.JSONEncoder.__init__(self, **kwargs) def default(self, obj): if isinstance(obj, HueApp): return obj.jsonable() return json.JSONEncoder.default(self, obj)