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Diffstat (limited to 'python/jinja2/bccache.py')
| -rw-r--r-- | python/jinja2/bccache.py | 362 |
1 files changed, 0 insertions, 362 deletions
diff --git a/python/jinja2/bccache.py b/python/jinja2/bccache.py deleted file mode 100644 index 080e527..0000000 --- a/python/jinja2/bccache.py +++ /dev/null @@ -1,362 +0,0 @@ -# -*- coding: utf-8 -*- -""" - jinja2.bccache - ~~~~~~~~~~~~~~ - - This module implements the bytecode cache system Jinja is optionally - using. This is useful if you have very complex template situations and - the compiliation of all those templates slow down your application too - much. - - Situations where this is useful are often forking web applications that - are initialized on the first request. - - :copyright: (c) 2017 by the Jinja Team. - :license: BSD. -""" -from os import path, listdir -import os -import sys -import stat -import errno -import marshal -import tempfile -import fnmatch -from hashlib import sha1 -from jinja2.utils import open_if_exists -from jinja2._compat import BytesIO, pickle, PY2, text_type - - -# marshal works better on 3.x, one hack less required -if not PY2: - marshal_dump = marshal.dump - marshal_load = marshal.load -else: - - def marshal_dump(code, f): - if isinstance(f, file): - marshal.dump(code, f) - else: - f.write(marshal.dumps(code)) - - def marshal_load(f): - if isinstance(f, file): - return marshal.load(f) - return marshal.loads(f.read()) - - -bc_version = 3 - -# magic version used to only change with new jinja versions. With 2.6 -# we change this to also take Python version changes into account. The -# reason for this is that Python tends to segfault if fed earlier bytecode -# versions because someone thought it would be a good idea to reuse opcodes -# or make Python incompatible with earlier versions. -bc_magic = 'j2'.encode('ascii') + \ - pickle.dumps(bc_version, 2) + \ - pickle.dumps((sys.version_info[0] << 24) | sys.version_info[1]) - - -class Bucket(object): - """Buckets are used to store the bytecode for one template. It's created - and initialized by the bytecode cache and passed to the loading functions. - - The buckets get an internal checksum from the cache assigned and use this - to automatically reject outdated cache material. Individual bytecode - cache subclasses don't have to care about cache invalidation. - """ - - def __init__(self, environment, key, checksum): - self.environment = environment - self.key = key - self.checksum = checksum - self.reset() - - def reset(self): - """Resets the bucket (unloads the bytecode).""" - self.code = None - - def load_bytecode(self, f): - """Loads bytecode from a file or file like object.""" - # make sure the magic header is correct - magic = f.read(len(bc_magic)) - if magic != bc_magic: - self.reset() - return - # the source code of the file changed, we need to reload - checksum = pickle.load(f) - if self.checksum != checksum: - self.reset() - return - # if marshal_load fails then we need to reload - try: - self.code = marshal_load(f) - except (EOFError, ValueError, TypeError): - self.reset() - return - - def write_bytecode(self, f): - """Dump the bytecode into the file or file like object passed.""" - if self.code is None: - raise TypeError('can\'t write empty bucket') - f.write(bc_magic) - pickle.dump(self.checksum, f, 2) - marshal_dump(self.code, f) - - def bytecode_from_string(self, string): - """Load bytecode from a string.""" - self.load_bytecode(BytesIO(string)) - - def bytecode_to_string(self): - """Return the bytecode as string.""" - out = BytesIO() - self.write_bytecode(out) - return out.getvalue() - - -class BytecodeCache(object): - """To implement your own bytecode cache you have to subclass this class - and override :meth:`load_bytecode` and :meth:`dump_bytecode`. Both of - these methods are passed a :class:`~jinja2.bccache.Bucket`. - - A very basic bytecode cache that saves the bytecode on the file system:: - - from os import path - - class MyCache(BytecodeCache): - - def __init__(self, directory): - self.directory = directory - - def load_bytecode(self, bucket): - filename = path.join(self.directory, bucket.key) - if path.exists(filename): - with open(filename, 'rb') as f: - bucket.load_bytecode(f) - - def dump_bytecode(self, bucket): - filename = path.join(self.directory, bucket.key) - with open(filename, 'wb') as f: - bucket.write_bytecode(f) - - A more advanced version of a filesystem based bytecode cache is part of - Jinja2. - """ - - def load_bytecode(self, bucket): - """Subclasses have to override this method to load bytecode into a - bucket. If they are not able to find code in the cache for the - bucket, it must not do anything. - """ - raise NotImplementedError() - - def dump_bytecode(self, bucket): - """Subclasses have to override this method to write the bytecode - from a bucket back to the cache. If it unable to do so it must not - fail silently but raise an exception. - """ - raise NotImplementedError() - - def clear(self): - """Clears the cache. This method is not used by Jinja2 but should be - implemented to allow applications to clear the bytecode cache used - by a particular environment. - """ - - def get_cache_key(self, name, filename=None): - """Returns the unique hash key for this template name.""" - hash = sha1(name.encode('utf-8')) - if filename is not None: - filename = '|' + filename - if isinstance(filename, text_type): - filename = filename.encode('utf-8') - hash.update(filename) - return hash.hexdigest() - - def get_source_checksum(self, source): - """Returns a checksum for the source.""" - return sha1(source.encode('utf-8')).hexdigest() - - def get_bucket(self, environment, name, filename, source): - """Return a cache bucket for the given template. All arguments are - mandatory but filename may be `None`. - """ - key = self.get_cache_key(name, filename) - checksum = self.get_source_checksum(source) - bucket = Bucket(environment, key, checksum) - self.load_bytecode(bucket) - return bucket - - def set_bucket(self, bucket): - """Put the bucket into the cache.""" - self.dump_bytecode(bucket) - - -class FileSystemBytecodeCache(BytecodeCache): - """A bytecode cache that stores bytecode on the filesystem. It accepts - two arguments: The directory where the cache items are stored and a - pattern string that is used to build the filename. - - If no directory is specified a default cache directory is selected. On - Windows the user's temp directory is used, on UNIX systems a directory - is created for the user in the system temp directory. - - The pattern can be used to have multiple separate caches operate on the - same directory. The default pattern is ``'__jinja2_%s.cache'``. ``%s`` - is replaced with the cache key. - - >>> bcc = FileSystemBytecodeCache('/tmp/jinja_cache', '%s.cache') - - This bytecode cache supports clearing of the cache using the clear method. - """ - - def __init__(self, directory=None, pattern='__jinja2_%s.cache'): - if directory is None: - directory = self._get_default_cache_dir() - self.directory = directory - self.pattern = pattern - - def _get_default_cache_dir(self): - def _unsafe_dir(): - raise RuntimeError('Cannot determine safe temp directory. You ' - 'need to explicitly provide one.') - - tmpdir = tempfile.gettempdir() - - # On windows the temporary directory is used specific unless - # explicitly forced otherwise. We can just use that. - if os.name == 'nt': - return tmpdir - if not hasattr(os, 'getuid'): - _unsafe_dir() - - dirname = '_jinja2-cache-%d' % os.getuid() - actual_dir = os.path.join(tmpdir, dirname) - - try: - os.mkdir(actual_dir, stat.S_IRWXU) - except OSError as e: - if e.errno != errno.EEXIST: - raise - try: - os.chmod(actual_dir, stat.S_IRWXU) - actual_dir_stat = os.lstat(actual_dir) - if actual_dir_stat.st_uid != os.getuid() \ - or not stat.S_ISDIR(actual_dir_stat.st_mode) \ - or stat.S_IMODE(actual_dir_stat.st_mode) != stat.S_IRWXU: - _unsafe_dir() - except OSError as e: - if e.errno != errno.EEXIST: - raise - - actual_dir_stat = os.lstat(actual_dir) - if actual_dir_stat.st_uid != os.getuid() \ - or not stat.S_ISDIR(actual_dir_stat.st_mode) \ - or stat.S_IMODE(actual_dir_stat.st_mode) != stat.S_IRWXU: - _unsafe_dir() - - return actual_dir - - def _get_cache_filename(self, bucket): - return path.join(self.directory, self.pattern % bucket.key) - - def load_bytecode(self, bucket): - f = open_if_exists(self._get_cache_filename(bucket), 'rb') - if f is not None: - try: - bucket.load_bytecode(f) - finally: - f.close() - - def dump_bytecode(self, bucket): - f = open(self._get_cache_filename(bucket), 'wb') - try: - bucket.write_bytecode(f) - finally: - f.close() - - def clear(self): - # imported lazily here because google app-engine doesn't support - # write access on the file system and the function does not exist - # normally. - from os import remove - files = fnmatch.filter(listdir(self.directory), self.pattern % '*') - for filename in files: - try: - remove(path.join(self.directory, filename)) - except OSError: - pass - - -class MemcachedBytecodeCache(BytecodeCache): - """This class implements a bytecode cache that uses a memcache cache for - storing the information. It does not enforce a specific memcache library - (tummy's memcache or cmemcache) but will accept any class that provides - the minimal interface required. - - Libraries compatible with this class: - - - `werkzeug <http://werkzeug.pocoo.org/>`_.contrib.cache - - `python-memcached <https://www.tummy.com/Community/software/python-memcached/>`_ - - `cmemcache <http://gijsbert.org/cmemcache/>`_ - - (Unfortunately the django cache interface is not compatible because it - does not support storing binary data, only unicode. You can however pass - the underlying cache client to the bytecode cache which is available - as `django.core.cache.cache._client`.) - - The minimal interface for the client passed to the constructor is this: - - .. class:: MinimalClientInterface - - .. method:: set(key, value[, timeout]) - - Stores the bytecode in the cache. `value` is a string and - `timeout` the timeout of the key. If timeout is not provided - a default timeout or no timeout should be assumed, if it's - provided it's an integer with the number of seconds the cache - item should exist. - - .. method:: get(key) - - Returns the value for the cache key. If the item does not - exist in the cache the return value must be `None`. - - The other arguments to the constructor are the prefix for all keys that - is added before the actual cache key and the timeout for the bytecode in - the cache system. We recommend a high (or no) timeout. - - This bytecode cache does not support clearing of used items in the cache. - The clear method is a no-operation function. - - .. versionadded:: 2.7 - Added support for ignoring memcache errors through the - `ignore_memcache_errors` parameter. - """ - - def __init__(self, client, prefix='jinja2/bytecode/', timeout=None, - ignore_memcache_errors=True): - self.client = client - self.prefix = prefix - self.timeout = timeout - self.ignore_memcache_errors = ignore_memcache_errors - - def load_bytecode(self, bucket): - try: - code = self.client.get(self.prefix + bucket.key) - except Exception: - if not self.ignore_memcache_errors: - raise - code = None - if code is not None: - bucket.bytecode_from_string(code) - - def dump_bytecode(self, bucket): - args = (self.prefix + bucket.key, bucket.bytecode_to_string()) - if self.timeout is not None: - args += (self.timeout,) - try: - self.client.set(*args) - except Exception: - if not self.ignore_memcache_errors: - raise |