remotefilelog: import Queue on Python 2, and queue on Python 3

Differential Revision: https://phab.mercurial-scm.org/D5599

hgext/remotefilelog/basestore.py

@@ -1,426 +1,425 b''
 from __future__ import absolute_import
 
 import errno
 import hashlib
 import os
 import shutil
 import stat
 import time
 
 from mercurial.i18n import _
 from mercurial.node import bin, hex
 from mercurial import (
     error,
     pycompat,
     util,
 )
 from . import (
     constants,
     shallowutil,
 )
 
 class basestore(object):
     def __init__(self, repo, path, reponame, shared=False):
         """Creates a remotefilelog store object for the given repo name.
 
         `path` - The file path where this store keeps its data
         `reponame` - The name of the repo. This is used to partition data from
         many repos.
         `shared` - True if this store is a shared cache of data from the central
         server, for many repos on this machine. False means this store is for
         the local data for one repo.
         """
         self.repo = repo
         self.ui = repo.ui
         self._path = path
         self._reponame = reponame
         self._shared = shared
         self._uid = os.getuid() if not pycompat.iswindows else None
 
         self._validatecachelog = self.ui.config("remotefilelog",
                                                 "validatecachelog")
         self._validatecache = self.ui.config("remotefilelog", "validatecache",
                                              'on')
         if self._validatecache not in ('on', 'strict', 'off'):
             self._validatecache = 'on'
         if self._validatecache == 'off':
             self._validatecache = False
 
         if shared:
             shallowutil.mkstickygroupdir(self.ui, path)
 
     def getmissing(self, keys):
         missing = []
         for name, node in keys:
             filepath = self._getfilepath(name, node)
             exists = os.path.exists(filepath)
             if (exists and self._validatecache == 'strict' and
                 not self._validatekey(filepath, 'contains')):
                 exists = False
             if not exists:
                 missing.append((name, node))
 
         return missing
 
     # BELOW THIS ARE IMPLEMENTATIONS OF REPACK SOURCE
 
     def markledger(self, ledger, options=None):
         if options and options.get(constants.OPTION_PACKSONLY):
             return
         if self._shared:
             for filename, nodes in self._getfiles():
                 for node in nodes:
                     ledger.markdataentry(self, filename, node)
                     ledger.markhistoryentry(self, filename, node)
 
     def cleanup(self, ledger):
         ui = self.ui
         entries = ledger.sources.get(self, [])
         count = 0
         progress = ui.makeprogress(_("cleaning up"), unit="files",
                                    total=len(entries))
         for entry in entries:
             if entry.gced or (entry.datarepacked and entry.historyrepacked):
                 progress.update(count)
                 path = self._getfilepath(entry.filename, entry.node)
                 util.tryunlink(path)
             count += 1
         progress.complete()
 
         # Clean up the repo cache directory.
         self._cleanupdirectory(self._getrepocachepath())
 
     # BELOW THIS ARE NON-STANDARD APIS
 
     def _cleanupdirectory(self, rootdir):
         """Removes the empty directories and unnecessary files within the root
         directory recursively. Note that this method does not remove the root
         directory itself. """
 
         oldfiles = set()
         otherfiles = set()
         # osutil.listdir returns stat information which saves some rmdir/listdir
         # syscalls.
         for name, mode in util.osutil.listdir(rootdir):
             if stat.S_ISDIR(mode):
                 dirpath = os.path.join(rootdir, name)
                 self._cleanupdirectory(dirpath)
 
                 # Now that the directory specified by dirpath is potentially
                 # empty, try and remove it.
                 try:
                     os.rmdir(dirpath)
                 except OSError:
                     pass
 
             elif stat.S_ISREG(mode):
                 if name.endswith('_old'):
                     oldfiles.add(name[:-4])
                 else:
                     otherfiles.add(name)
 
         # Remove the files which end with suffix '_old' and have no
         # corresponding file without the suffix '_old'. See addremotefilelognode
         # method for the generation/purpose of files with '_old' suffix.
         for filename in oldfiles - otherfiles:
             filepath = os.path.join(rootdir, filename + '_old')
             util.tryunlink(filepath)
 
     def _getfiles(self):
         """Return a list of (filename, [node,...]) for all the revisions that
         exist in the store.
 
         This is useful for obtaining a list of all the contents of the store
         when performing a repack to another store, since the store API requires
         name+node keys and not namehash+node keys.
         """
         existing = {}
         for filenamehash, node in self._listkeys():
             existing.setdefault(filenamehash, []).append(node)
 
         filenamemap = self._resolvefilenames(existing.keys())
 
         for filename, sha in filenamemap.iteritems():
             yield (filename, existing[sha])
 
     def _resolvefilenames(self, hashes):
         """Given a list of filename hashes that are present in the
         remotefilelog store, return a mapping from filename->hash.
 
         This is useful when converting remotefilelog blobs into other storage
         formats.
         """
         if not hashes:
             return {}
 
         filenames = {}
         missingfilename = set(hashes)
 
         # Start with a full manifest, since it'll cover the majority of files
         for filename in self.repo['tip'].manifest():
             sha = hashlib.sha1(filename).digest()
             if sha in missingfilename:
                 filenames[filename] = sha
                 missingfilename.discard(sha)
 
         # Scan the changelog until we've found every file name
         cl = self.repo.unfiltered().changelog
         for rev in pycompat.xrange(len(cl) - 1, -1, -1):
             if not missingfilename:
                 break
             files = cl.readfiles(cl.node(rev))
             for filename in files:
                 sha = hashlib.sha1(filename).digest()
                 if sha in missingfilename:
                     filenames[filename] = sha
                     missingfilename.discard(sha)
 
         return filenames
 
     def _getrepocachepath(self):
         return os.path.join(
             self._path, self._reponame) if self._shared else self._path
 
     def _listkeys(self):
         """List all the remotefilelog keys that exist in the store.
 
         Returns a iterator of (filename hash, filecontent hash) tuples.
         """
 
         for root, dirs, files in os.walk(self._getrepocachepath()):
             for filename in files:
                 if len(filename) != 40:
                     continue
                 node = filename
                 if self._shared:
                     # .../1a/85ffda..be21
                     filenamehash = root[-41:-39] + root[-38:]
                 else:
                     filenamehash = root[-40:]
                 yield (bin(filenamehash), bin(node))
 
     def _getfilepath(self, name, node):
         node = hex(node)
         if self._shared:
             key = shallowutil.getcachekey(self._reponame, name, node)
         else:
             key = shallowutil.getlocalkey(name, node)
 
         return os.path.join(self._path, key)
 
     def _getdata(self, name, node):
         filepath = self._getfilepath(name, node)
         try:
             data = shallowutil.readfile(filepath)
             if self._validatecache and not self._validatedata(data, filepath):
                 if self._validatecachelog:
                     with open(self._validatecachelog, 'a+') as f:
                         f.write("corrupt %s during read\n" % filepath)
                 os.rename(filepath, filepath + ".corrupt")
                 raise KeyError("corrupt local cache file %s" % filepath)
         except IOError:
             raise KeyError("no file found at %s for %s:%s" % (filepath, name,
                                                               hex(node)))
 
         return data
 
     def addremotefilelognode(self, name, node, data):
         filepath = self._getfilepath(name, node)
 
         oldumask = os.umask(0o002)
         try:
             # if this node already exists, save the old version for
             # recovery/debugging purposes.
             if os.path.exists(filepath):
                 newfilename = filepath + '_old'
                 # newfilename can be read-only and shutil.copy will fail.
                 # Delete newfilename to avoid it
                 if os.path.exists(newfilename):
                     shallowutil.unlinkfile(newfilename)
                 shutil.copy(filepath, newfilename)
 
             shallowutil.mkstickygroupdir(self.ui, os.path.dirname(filepath))
             shallowutil.writefile(filepath, data, readonly=True)
 
             if self._validatecache:
                 if not self._validatekey(filepath, 'write'):
                     raise error.Abort(_("local cache write was corrupted %s") %
                                       filepath)
         finally:
             os.umask(oldumask)
 
     def markrepo(self, path):
         """Call this to add the given repo path to the store's list of
         repositories that are using it. This is useful later when doing garbage
         collection, since it allows us to insecpt the repos to see what nodes
         they want to be kept alive in the store.
         """
         repospath = os.path.join(self._path, "repos")
         with open(repospath, 'ab') as reposfile:
             reposfile.write(os.path.dirname(path) + "\n")
 
         repospathstat = os.stat(repospath)
         if repospathstat.st_uid == self._uid:
             os.chmod(repospath, 0o0664)
 
     def _validatekey(self, path, action):
         with open(path, 'rb') as f:
             data = f.read()
 
         if self._validatedata(data, path):
             return True
 
         if self._validatecachelog:
             with open(self._validatecachelog, 'ab+') as f:
                 f.write("corrupt %s during %s\n" % (path, action))
 
         os.rename(path, path + ".corrupt")
         return False
 
     def _validatedata(self, data, path):
         try:
             if len(data) > 0:
                 # see remotefilelogserver.createfileblob for the format
                 offset, size, flags = shallowutil.parsesizeflags(data)
                 if len(data) <= size:
                     # it is truncated
                     return False
 
                 # extract the node from the metadata
                 offset += size
                 datanode = data[offset:offset + 20]
 
                 # and compare against the path
                 if os.path.basename(path) == hex(datanode):
                     # Content matches the intended path
                     return True
                 return False
         except (ValueError, RuntimeError):
             pass
 
         return False
 
     def gc(self, keepkeys):
         ui = self.ui
         cachepath = self._path
 
         # prune cache
-        import Queue
-        queue = Queue.PriorityQueue()
+        queue = pycompat.queue.PriorityQueue()
         originalsize = 0
         size = 0
         count = 0
         removed = 0
 
         # keep files newer than a day even if they aren't needed
         limit = time.time() - (60 * 60 * 24)
 
         progress = ui.makeprogress(_("removing unnecessary files"),
                                    unit="files")
         progress.update(0)
         for root, dirs, files in os.walk(cachepath):
             for file in files:
                 if file == 'repos':
                     continue
 
                 # Don't delete pack files
                 if '/packs/' in root:
                     continue
 
                 progress.update(count)
                 path = os.path.join(root, file)
                 key = os.path.relpath(path, cachepath)
                 count += 1
                 try:
                     pathstat = os.stat(path)
                 except OSError as e:
                     # errno.ENOENT = no such file or directory
                     if e.errno != errno.ENOENT:
                         raise
                     msg = _("warning: file %s was removed by another process\n")
                     ui.warn(msg % path)
                     continue
 
                 originalsize += pathstat.st_size
 
                 if key in keepkeys or pathstat.st_atime > limit:
                     queue.put((pathstat.st_atime, path, pathstat))
                     size += pathstat.st_size
                 else:
                     try:
                         shallowutil.unlinkfile(path)
                     except OSError as e:
                         # errno.ENOENT = no such file or directory
                         if e.errno != errno.ENOENT:
                             raise
                         msg = _("warning: file %s was removed by another "
                                 "process\n")
                         ui.warn(msg % path)
                         continue
                     removed += 1
         progress.complete()
 
         # remove oldest files until under limit
         limit = ui.configbytes("remotefilelog", "cachelimit")
         if size > limit:
             excess = size - limit
             progress = ui.makeprogress(_("enforcing cache limit"), unit="bytes",
                                        total=excess)
             removedexcess = 0
             while queue and size > limit and size > 0:
                 progress.update(removedexcess)
                 atime, oldpath, oldpathstat = queue.get()
                 try:
                     shallowutil.unlinkfile(oldpath)
                 except OSError as e:
                     # errno.ENOENT = no such file or directory
                     if e.errno != errno.ENOENT:
                         raise
                     msg = _("warning: file %s was removed by another process\n")
                     ui.warn(msg % oldpath)
                 size -= oldpathstat.st_size
                 removed += 1
                 removedexcess += oldpathstat.st_size
             progress.complete()
 
         ui.status(_("finished: removed %d of %d files (%0.2f GB to %0.2f GB)\n")
                   % (removed, count,
                      float(originalsize) / 1024.0 / 1024.0 / 1024.0,
                      float(size) / 1024.0 / 1024.0 / 1024.0))
 
 class baseunionstore(object):
     def __init__(self, *args, **kwargs):
         # If one of the functions that iterates all of the stores is about to
         # throw a KeyError, try this many times with a full refresh between
         # attempts. A repack operation may have moved data from one store to
         # another while we were running.
         self.numattempts = kwargs.get(r'numretries', 0) + 1
         # If not-None, call this function on every retry and if the attempts are
         # exhausted.
         self.retrylog = kwargs.get(r'retrylog', None)
 
     def markforrefresh(self):
         for store in self.stores:
             if util.safehasattr(store, 'markforrefresh'):
                 store.markforrefresh()
 
     @staticmethod
     def retriable(fn):
         def noop(*args):
             pass
         def wrapped(self, *args, **kwargs):
             retrylog = self.retrylog or noop
             funcname = fn.__name__
             for i in pycompat.xrange(self.numattempts):
                 if i > 0:
                     retrylog('re-attempting (n=%d) %s\n' % (i, funcname))
                     self.markforrefresh()
                 try:
                     return fn(self, *args, **kwargs)
                 except KeyError:
                     pass
             # retries exhausted
             retrylog('retries exhausted in %s, raising KeyError\n' %
                      pycompat.sysbytes(funcname))
             raise
         return wrapped