Current Path : /usr/share/pyshared/axi/ |
Current File : //usr/share/pyshared/axi/indexer.py |
# -*- coding: utf-8 -*- # # axi/indexer.py - apt-xapian-index indexer # # Copyright (C) 2007--2010 Enrico Zini <enrico@debian.org> # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # import axi import sys import os import imp import socket, errno import fcntl import textwrap import xapian import shutil import itertools import time import re import urllib import cPickle as pickle APTLISTDIR="/var/lib/apt/lists" class Addon: """ Indexer plugin wrapper """ def __init__(self, fname, **kw): self.filename = os.path.basename(fname) self.name = os.path.splitext(self.filename)[0] oldpath = sys.path try: sys.path.append(os.path.dirname(fname)) self.module = imp.load_source("axi.plugin_" + self.name, fname) finally: sys.path = oldpath try: self.obj = self.module.init(**kw) except TypeError: self.obj = self.module.init() if self.obj: try: self.info = self.obj.info(**kw) except TypeError: self.info = self.obj.info() def finished(self): if hasattr(self.obj, "finished"): self.obj.finished() def send_extra_info(self, **kw): func = getattr(self.obj, "send_extra_info", None) if func is not None: func(**kw) class Plugins(list): def __init__(self, **kw): """ Read the plugins, in sorted order. Pass all the keyword args to the plugin init """ if "langs" not in kw: kw["langs"] = self.scan_available_languages() progress = kw.get("progress", None) self.disabled = [] for fname in sorted(os.listdir(axi.PLUGINDIR)): # Skip non-pythons, hidden files and python sources starting with '_' if fname[0] in ['.', '_'] or not fname.endswith(".py"): continue fullname = os.path.join(axi.PLUGINDIR, fname) if not os.path.isfile(fullname): continue if progress: progress.verbose("Reading plugin %s." % fullname) addon = Addon(fullname, **kw) if addon.obj != None: self.append(addon) def scan_available_languages(self): # Languages we index langs = set() # Look for files like: ftp.uk.debian.org_debian_dists_sid_main_i18n_Translation-it # And extract the language code at the end tfile = re.compile(r"_i18n_Translation-([^-]+)$") for f in os.listdir(APTLISTDIR): mo = tfile.search(f) if not mo: continue langs.add(urllib.unquote(mo.group(1))) return langs class Progress: """ Normal progress report to stdout """ def __init__(self): self.task = None self.halfway = False self.is_verbose = False def begin(self, task): self.task = task print "%s..." % self.task, sys.stdout.flush() self.halfway = True def progress(self, percent): print "\r%s... %d%%" % (self.task, percent), sys.stdout.flush() self.halfway = True def end(self): print "\r%s: done. " % self.task self.halfway = False def verbose(self, *args): if not self.is_verbose: return if self.halfway: print print " ".join(args) self.halfway = False def notice(self, *args): if self.halfway: print print >>sys.stderr, " ".join(args) self.halfway = False def warning(self, *args): if self.halfway: print print >>sys.stderr, " ".join(args) self.halfway = False def error(self, *args): if self.halfway: print print >>sys.stderr, " ".join(args) self.halfway = False class BatchProgress: """ Machine readable progress report """ def __init__(self): self.task = None def begin(self, task): self.task = task print "begin: %s\n" % self.task, sys.stdout.flush() def progress(self, percent): print "progress: %d/100\n" % percent, sys.stdout.flush() def end(self): print "done: %s\n" % self.task sys.stdout.flush() def verbose(self, *args): print "verbose: %s" % (" ".join(args)) sys.stdout.flush() def notice(self, *args): print "notice: %s" % (" ".join(args)) sys.stdout.flush() def warning(self, *args): print "warning: %s" % (" ".join(args)) sys.stdout.flush() def error(self, *args): print "error: %s" % (" ".join(args)) sys.stdout.flush() class SilentProgress: """ Quiet progress report """ def begin(self, task): pass def progress(self, percent): pass def end(self): pass def verbose(self, *args): pass def notice(self, *args): pass def warning(self, *args): print >>sys.stderr, " ".join(args) def error(self, *args): print >>sys.stderr, " ".join(args) class ClientProgress: """ Client-side progress report, reporting progress from another running indexer """ def __init__(self, progress): self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) self.sock.settimeout(None) self.sock.connect(axi.XAPIANDBUPDATESOCK) self.progress = progress def loop(self): hasBegun = False while True: msg = self.sock.recv(4096) try: args = pickle.loads(msg) except EOFError: self.progress.error("The other update has stopped") return action = args[0] args = args[1:] if action == "begin": self.progress.begin(*args) hasBegun = True elif action == "progress": if not hasBegun: self.progress.begin(args[0]) hasBegun = True self.progress.progress(*args[1:]) elif action == "end": if not hasBegun: self.progress.begin(args[0]) hasBegun = True self.progress.end(*args[1:]) elif action == "verbose": self.progress.verbose(*args) elif action == "notice": self.progress.notice(*args) elif action == "error": self.progress.error(*args) elif action == "alldone": break else: self.progress.error("unknown action '%s' from other update-apt-xapian-index. Arguments: '%s'" % (action, ", ".join(map(repr, args)))) class ServerSenderProgress: """ Server endpoint for client-server progress report """ def __init__(self, sock, task = None): self.sock = sock self.task = task def __del__(self): self._send(pickle.dumps(("alldone",))) def _send(self, text): try: self.sock.send(text) except: pass def begin(self, task): self.task = task self._send(pickle.dumps(("begin", self.task))) def progress(self, percent): self._send(pickle.dumps(("progress", self.task, percent))) def end(self): self._send(pickle.dumps(("end", self.task))) def verbose(self, *args): self._send(pickle.dumps(("verbose",) + args)) def notice(self, *args): self._send(pickle.dumps(("notice",) + args)) def warning(self, *args): self._send(pickle.dumps(("warning",) + args)) def error(self, *args): self._send(pickle.dumps(("error",) + args)) class ServerProgress: """ Send progress report to any progress object, as well as to client indexers """ def __init__(self, mine): self.task = None self.proxied = [mine] self.sockfile = axi.XAPIANDBUPDATESOCK try: os.unlink(self.sockfile) except OSError: pass self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) self.sock.bind(axi.XAPIANDBUPDATESOCK) self.sock.setblocking(False) self.sock.listen(5) # Disallowing unwanted people to mess with the file is automatic, as # the socket has the ownership of the user we're using, and people # can't connect to it unless they can write to it def __del__(self): self.sock.close() os.unlink(self.sockfile) def _check(self): try: sock = self.sock.accept()[0] self.proxied.append(ServerSenderProgress(sock, self.task)) except socket.error, e: if e.args[0] != errno.EAGAIN: raise pass def begin(self, task): self._check() self.task = task for x in self.proxied: x.begin(task) def progress(self, percent): self._check() for x in self.proxied: x.progress(percent) def end(self): self._check() for x in self.proxied: x.end() def verbose(self, *args): self._check() for x in self.proxied: x.verbose(*args) def notice(self, *args): self._check() for x in self.proxied: x.notice(*args) def warning(self, *args): self._check() for x in self.proxied: x.warning(*args) def error(self, *args): self._check() for x in self.proxied: x.error(*args) class ExecutionTime(object): """ Helper that can be used in with statements to have a simple measure of the timing of a particular block of code, e.g. with ExecutionTime("db flush"): db.flush() """ import time def __init__(self, info=""): self.info = info def __enter__(self): self.now = time.time() def __exit__(self, type, value, stack): print "%s: %s" % (self.info, time.time() - self.now) class Indexer(object): """ The indexer """ def __init__(self, progress, quietapt=False): self.progress = progress self.quietapt = quietapt self.verbose = getattr(progress, "is_verbose", False) # Timestamp of the most recent data source self.ds_timestamp = 0 # Apt cache instantiated on demand self.apt_cache = None # Loaded plugins self.plugins = None # OS file handle for the lock file self.lockfd = None # Ensure the database and cache directories exist self.ensure_dir_exists(axi.XAPIANDBPATH) self.ensure_dir_exists(axi.XAPIANCACHEPATH) def ensure_dir_exists(self, pathname): """ Create a directory if missing, but do not complain if it already exists """ try: # Try to create it anyway os.mkdir(pathname) except OSError, e: if e.errno != errno.EEXIST: # If we got an error besides path already existing, fail raise elif not os.path.isdir(pathname): # If that path already exists, but is not a directory, also fail raise def _test_wrap_apt_cache(self, wrapper): """ Wrap the apt-cache in some proxy object. This is used to give tests some control over the apt cache results """ if self.apt_cache is not None: raise RuntimeError("the cache has already been instantiated") # Instantiate the cache self.aptcache() # Wrap it self.apt_cache = wrapper(self.apt_cache) def aptcache(self): if not self.apt_cache: #import warnings ## Yes, apt, thanks, I know, the api isn't stable, thank you so very much ##warnings.simplefilter('ignore', FutureWarning) #warnings.filterwarnings("ignore","apt API not stable yet") import apt import apt_pkg #warnings.resetwarnings() if self.quietapt: class AptSilentProgress(apt.progress.text.OpProgress) : def __init__(self): pass def done(self): pass def update(self,percent=None): pass aptprogress = AptSilentProgress() else: aptprogress = None # memonly=True: force apt to not write a pkgcache.bin apt_pkg.init_config() self.apt_cache = apt.Cache(memonly=True, progress=aptprogress) return self.apt_cache def lock(self): """ Lock the session to prevent further updates. @returns True if the session is locked False if another indexer is running """ # Lock the session so that we prevent concurrent updates self.lockfd = os.open(axi.XAPIANDBLOCK, os.O_RDWR | os.O_CREAT) try: fcntl.lockf(self.lockfd, fcntl.LOCK_EX | fcntl.LOCK_NB) # Wrap the current progress with the server sender self.progress = ServerProgress(self.progress) return True except IOError, e: if e.errno == errno.EACCES or e.errno == errno.EAGAIN: return False else: raise def slave(self): """ Attach to a running indexer and report its progress. Return when the other indexer has finished. """ self.progress.notice("Another update is already running: showing its progress.") childProgress = ClientProgress(self.progress) childProgress.loop() def setupIndexing(self, force=False, system=True): """ Setup indexing: read plugins, check timestamps... @param force: if True, reindex also if the index is up to date @return: True if there is something to index False if there is no need of indexing """ # Read values database #values = readValueDB(VALUESCONF, progress) # Read the plugins, in sorted order self.plugins = Plugins(progress=self.progress, system=system) # Ensure that we have something to do if len(self.plugins) == 0: self.progress.notice("No indexing plugins found in %s" % axi.PLUGINDIR) return False # Get the most recent modification timestamp of the data sources self.ds_timestamp = max([x.info['timestamp'] for x in self.plugins]) # Get the timestamp of the last database update try: if os.path.exists(axi.XAPIANDBSTAMP): cur_timestamp = os.path.getmtime(axi.XAPIANDBSTAMP) else: cur_timestamp = 0 except OSError, e: cur_timestamp = 0 self.progress.notice("Reading current timestamp failed: %s. Assuming the index has not been created yet." % e) if self.verbose: self.progress.verbose("Most recent dataset: %s." % time.ctime(self.ds_timestamp)) self.progress.verbose("Most recent update for: %s." % time.ctime(cur_timestamp)) # See if we need an update if cur_timestamp != 0 and int(self.ds_timestamp+.5) <= int(cur_timestamp+0.5): if force: self.progress.notice("The index %s is up to date, but rebuilding anyway as requested." % axi.XAPIANDBPATH) else: self.progress.notice("The index %s is up to date" % axi.XAPIANDBPATH) return False # Build the value database self.progress.verbose("Aggregating value information.") # Read existing value database to keep ids stable in a system self.values, self.values_desc = axi.readValueDB(quiet=True) values_seq = max(self.values.values()) + 1 for addon in self.plugins: for v in addon.info.get("values", []): if v['name'] in self.values: continue self.values[v['name']] = values_seq values_seq += 1 self.values_desc[v['name']] = v['desc'] # Tell the plugins to do the long initialisation bits self.progress.verbose("Initializing plugins.") for addon in self.plugins: addon.obj.init(dict(values=self.values), self.progress) return True def get_document_from_apt(self, pkg): """ Get a xapian.Document for the given apt package record """ document = xapian.Document() # The document data is the package name document.set_data(pkg.name) # add information about the version of the package in slot 0 document.add_value(0, pkg.candidate.version) # Index the package name with a special prefix, to be able to find this # document by exact package name match document.add_term("XP"+pkg.name) # Have all the various plugins index their things for addon in self.plugins: addon.obj.index(document, pkg) return document def get_document_from_deb822(self, pkg): """ Get a xapian.Document for the given deb822 package record """ document = xapian.Document() # The document data is the package name document.set_data(pkg["Package"]) # add information about the version of the package in slot 0 document.add_value(0, pkg["Version"]) # Index the package name with a special prefix, to be able to find this # document by exact package name match document.add_term("XP"+pkg["Package"]) # Have all the various plugins index their things for addon in self.plugins: addon.obj.indexDeb822(document, pkg) return document def gen_documents_apt(self): """ Generate Xapian documents from an apt cache """ cache = self.aptcache() count = len(cache) for idx, pkg in enumerate(cache): if not pkg.candidate: continue # multiarch: do not index foreign arch if there is a native # archive version available (unless the pkg is installed) if (not pkg.installed and ":" in pkg.name and pkg.name.split(":")[0] in cache): continue # Print progress if idx % 200 == 0: self.progress.progress(100*idx/count) yield self.get_document_from_apt(pkg) def gen_documents_deb822(self, fnames): try: from debian import deb822 except ImportError: from debian_bundle import deb822 seen = set() for fname in fnames: infd = open(fname) # Get file size to compute progress total = os.fstat(infd.fileno())[6] for idx, pkg in enumerate(deb822.Deb822.iter_paragraphs(infd)): name = pkg["Package"] if name in seen: continue seen.add(name) # Print approximate progress by checking the current read position # against the file size if total > 0 and idx % 200 == 0: cur = infd.tell() self.progress.progress(100*cur/total) yield self.get_document_from_deb822(pkg) def compareCacheToDb(self, cache, db): """ Compare the apt cache to the database and return dicts of the form (pkgname, docid) for the following states: unchanged - no new version since the last update outdated - a new version since the last update obsolete - no longer in the apt cache """ unchanged = {} outdated = {} obsolete = {} self.progress.begin("Reading Xapian index") count = db.get_doccount() for (idx, m) in enumerate(db.postlist("")): if idx % 5000 == 0: self.progress.progress(100*idx/count) doc = db.get_document(m.docid) pkg = doc.get_data() # this will return '' if there is no value 0, which is fine because it # will fail the comparison with the candidate version causing a reindex dbver = doc.get_value(0) # check if the package no longer exists if not cache.has_key(pkg) or not cache[pkg].candidate: obsolete[pkg] = m.docid # check if we have a new version, we do not have to delete # the record, elif cache[pkg].candidate.version != dbver: outdated[pkg] = m.docid # its a valid package and we know about it already else: unchanged[pkg] = m.docid self.progress.end() return unchanged, outdated, obsolete def is_cjk_enabled (self): return "XAPIAN_CJK_NGRAM" in os.environ def updateIndex(self, pathname): """ Update the index """ try: db = xapian.WritableDatabase(pathname, xapian.DB_CREATE_OR_OPEN) except xapian.DatabaseLockError, e: self.progress.warning("DB Update failed, database locked") return # Make sure the index CJK-compatible if self.is_cjk_enabled() and db.get_metadata("cjk_ngram") != "1": self.progress.notice("The index %s is not CJK-compatible, rebuilding it" % axi.XAPIANINDEX) return self.rebuild() cache = self.aptcache() count = len(cache) unchanged, outdated, obsolete = self.compareCacheToDb(cache, db) self.progress.verbose("Unchanged versions: %s, oudated version: %s, " "obsolete versions: %s" % (len(unchanged), len(outdated), len(obsolete))) self.progress.begin("Updating Xapian index") for a in self.plugins: a.send_extra_info(db=db, aptcache=cache) for idx, pkg in enumerate(cache): if idx % 1000 == 0: self.progress.progress(100*idx/count) if not pkg.candidate: continue if pkg.name in unchanged: continue elif pkg.name in outdated: # update the existing db.replace_document(outdated[pkg.name], self.get_document_from_apt(pkg)) else: # add the new ones db.add_document(self.get_document_from_apt(pkg)) # and remove the obsoletes for docid in obsolete.values(): db.delete_document(docid) # finished for a in self.plugins: a.finished() db.flush() self.progress.end() def incrementalUpdate(self): if not os.path.exists(axi.XAPIANINDEX): self.progress.notice("No Xapian index built yet: falling back to full rebuild") return self.rebuild() dbkind, dbpath = open(axi.XAPIANINDEX).readline().split() self.updateIndex(dbpath) # Update the index timestamp if not os.path.exists(axi.XAPIANDBSTAMP): open(axi.XAPIANDBSTAMP, "w").close() if self.ds_timestamp > 0: os.utime(axi.XAPIANDBSTAMP, (self.ds_timestamp, self.ds_timestamp)) def buildIndex(self, pathname, documents, addoninfo={}): """ Create a new Xapian index with the content provided by the plugins """ self.progress.begin("Rebuilding Xapian index") # Create a new Xapian index db = xapian.WritableDatabase(pathname, xapian.DB_CREATE_OR_OVERWRITE) # Mark the new index as CJK-enabled if relevant if self.is_cjk_enabled(): db.set_metadata("cjk_ngram", "1") # It seems to be faster without transactions, at the moment #db.begin_transaction(False) for a in self.plugins: a.send_extra_info(db=db) # Add all generated documents to the index for doc in documents: db.add_document(doc) #db.commit_transaction(); for a in self.plugins: a.finished() db.flush() self.progress.end() def rebuild(self, pkgfiles=None): # Create a new Xapian index with the content provided by the plugins # Xapian takes care of preventing concurrent updates and removing the old # database if it's left over by a previous crashed update # Generate a new index name for idx in itertools.count(1): tmpidxfname = "index.%d" % idx dbdir = os.path.join(axi.XAPIANCACHEPATH, tmpidxfname) if not os.path.exists(dbdir): break; if pkgfiles: generator = self.gen_documents_deb822(pkgfiles) else: for a in self.plugins: a.send_extra_info(aptcache=self.aptcache()) generator = self.gen_documents_apt() self.buildIndex(dbdir, generator) # Update the 'index' symlink to point at the new index self.progress.verbose("Installing the new index.") #os.symlink(tmpidxfname, axi.XAPIANDBPATH + "/index.tmp") out = open(axi.XAPIANINDEX + ".tmp", "w") print >>out, "auto", os.path.abspath(dbdir) out.close() os.rename(axi.XAPIANINDEX + ".tmp", axi.XAPIANINDEX) # Remove all other index.* directories that are not the newly created one def cleanoldcaches(dir): for file in os.listdir(dir): if not file.startswith("index."): continue # Don't delete what we just created if file == tmpidxfname: continue fullpath = os.path.join(dir, file) # Only delete directories if not os.path.isdir(fullpath): continue self.progress.verbose("Removing old index %s." % fullpath) shutil.rmtree(fullpath) cleanoldcaches(axi.XAPIANDBPATH) cleanoldcaches(axi.XAPIANCACHEPATH) # Commit the changes and update the last update timestamp if not os.path.exists(axi.XAPIANDBSTAMP): open(axi.XAPIANDBSTAMP, "w").close() if self.ds_timestamp > 0: os.utime(axi.XAPIANDBSTAMP, (self.ds_timestamp, self.ds_timestamp)) self.writeValues() self.writePrefixes() self.writeDoc() def writePrefixes(self, pathname=axi.XAPIANDBPREFIXES): """ Write the prefix information on the given file """ self.progress.verbose("Writing prefix information to %s." % pathname) out = open(pathname+".tmp", "w") print >>out, textwrap.dedent(""" # This file contains the information about keyword prefixes used in the # APT Xapian index. # # Xapian allows to prefix some terms so they can be told apart from # normal keywords: this is used for example with Debtags tags, and # stemmed forms. # # This file lists terms with their index prefix, their queryparser # prefix, whether queryparser should treat it as boolean or # probabilistic and a short description. """).lstrip() # Aggregate and normalise prefix information from all the plugins prefixes = dict() for addon in self.plugins: for p in addon.info.get("prefixes", []): idx = p.get("idx", None) if idx is None: continue qp = p.get("qp", None) type = p.get("type", None) desc = p.get("desc", None) # TODO: warn of inconsistencies (plugins that disagree on qp or type) old = prefixes.setdefault(idx, dict()) if qp: old.setdefault("qp", qp) if type: old.setdefault("type", type) if desc: old.setdefault("desc", desc) for name, info in sorted(prefixes.iteritems(), key=lambda x: x[0]): print >>out, "%s\t%s\t%s\t# %s" % ( name, info.get("qp", "-"), info.get("type", "-"), info.get("desc", "(description is missing)")) out.close() # Atomic update of the documentation os.rename(pathname+".tmp", pathname) def writeValues(self, pathname=axi.XAPIANDBVALUES): """ Write the value information on the given file """ self.progress.verbose("Writing value information to %s." % pathname) out = open(pathname+".tmp", "w") print >>out, textwrap.dedent(""" # This file contains the mapping between names of numeric values indexed in the # APT Xapian index and their index # # Xapian allows to index numeric values as well as keywords and to use them for # all sorts of useful querying tricks. However, every numeric value needs to # have a unique index, and this configuration file is needed to record which # indices are allocated and to provide a mnemonic name for them. # # The format is exactly like /etc/services with name, number and optional # aliases, with the difference that the second column does not use the # "/protocol" part, which would be meaningless here. """).lstrip() for name, idx in sorted(self.values.iteritems(), key=lambda x: x[1]): desc = self.values_desc[name] print >>out, "%s\t%d\t# %s" % (name, idx, desc) out.close() # Atomic update of the documentation os.rename(pathname+".tmp", pathname) def writeDoc(self, pathname=axi.XAPIANDBDOC): """ Write the documentation in the given file """ self.progress.verbose("Writing documentation to %s." % pathname) # Collect the documentation docinfo = [] for addon in self.plugins: try: doc = addon.obj.doc() if doc != None: docinfo.append(dict( name = doc['name'], shortDesc = doc['shortDesc'], fullDoc = doc['fullDoc'])) except: # If a plugin has problem returning documentation, don't worry about it self.progress.notice("Skipping documentation for plugin", addon.filename) # Write the documentation in pathname out = open(pathname+".tmp", "w") print >>out, textwrap.dedent(""" =============== Database layout =============== This Xapian database indexes Debian package information. To query the database, open it as ``%s/index``. Data are indexed either as terms or as values. Words found in package descriptions are indexed lowercase, and all other kinds of terms have an uppercase prefix as documented below. Numbers are indexed as Xapian numeric values. A list of the meaning of the numeric values is found in ``%s``. The data sources used for indexing are: """).lstrip() % (axi.XAPIANDBPATH, axi.XAPIANDBVALUES) for d in docinfo: print >>out, " * %s: %s" % (d['name'], d['shortDesc']) print >>out, textwrap.dedent(""" This Xapian index follows the conventions for term prefixes described in ``/usr/share/doc/xapian-omega/termprefixes.txt.gz``. Extra Debian data sources can define more extended prefixes (starting with ``X``): their meaning is documented below together with the rest of the data source documentation. At the very least, at least the package name (with the ``XP`` prefix) will be present in every document in the database. This allows to quickly lookup a Xapian document by package name. The user data associated to a Xapian document is the package name. ------------------- Active data sources ------------------- """) for d in docinfo: print >>out, d['name'] print >>out, '='*len(d['name']) print >>out, textwrap.dedent(d['fullDoc']) print >>out out.close() # Atomic update of the documentation os.rename(pathname+".tmp", pathname)