| # Copyright (c) 2010 The Chromium OS Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| # |
| # Adapted from portage/getbinpkg.py -- Portage binary-package helper functions |
| # Copyright 2003-2004 Gentoo Foundation |
| # Distributed under the terms of the GNU General Public License v2 |
| |
| import operator |
| import os |
| import tempfile |
| import time |
| import urllib2 |
| |
| class PackageIndex(object): |
| """A parser for the Portage Packages index file. |
| |
| The Portage Packages index file serves to keep track of what packages are |
| included in a tree. It contains the following sections: |
| 1) The header. The header tracks general key/value pairs that don't apply |
| to any specific package. E.g., it tracks the base URL of the packages |
| file, and the number of packages included in the file. The header is |
| terminated by a blank line. |
| 2) The body. The body is a list of packages. Each package contains a list |
| of key/value pairs. Packages are either terminated by a blank line or |
| by the end of the file. Every package has a CPV entry, which serves as |
| a unique identifier for the package. |
| """ |
| |
| def __init__(self): |
| """Constructor.""" |
| |
| # The header tracks general key/value pairs that don't apply to any |
| # specific package. E.g., it tracks the base URL of the packages. |
| self.header = {} |
| |
| # A list of packages (stored as a list of dictionaries). |
| self.packages = [] |
| |
| # Whether or not the PackageIndex has been modified since the last time it |
| # was written. |
| self.modified = False |
| |
| def _PopulateDuplicateDB(self, db): |
| """Populate db with SHA1 -> URL mapping for packages. |
| |
| Args: |
| db: Dictionary to populate with SHA1 -> URL mapping for packages. |
| """ |
| |
| uri = self.header['URI'] |
| for pkg in self.packages: |
| cpv, sha1 = pkg['CPV'], pkg.get('SHA1') |
| if sha1: |
| path = pkg.get('PATH', cpv + '.tbz2') |
| db[sha1] = '%s/%s' % (uri.rstrip('/'), path) |
| |
| def _ReadPkgIndex(self, pkgfile): |
| """Read a list of key/value pairs from the Packages file into a dictionary. |
| |
| Both header entries and package entries are lists of key/value pairs, so |
| they can both be read by this function. Entries can be terminated by empty |
| lines or by the end of the file. |
| |
| This function will read lines from the specified file until it encounters |
| the a blank line or the end of the file. |
| |
| Keys and values in the Packages file are separated by a colon and a space. |
| Keys may contain capital letters, numbers, and underscores, but may not |
| contain colons. Values may contain any character except a newline. In |
| particular, it is normal for values to contain colons. |
| |
| Lines that have content, and do not contain a valid key/value pair, are |
| ignored. This is for compatibility with the Portage package parser, and |
| to allow for future extensions to the Packages file format. |
| |
| All entries must contain at least one key/value pair. If the end of the |
| fils is reached, an empty dictionary is returned. |
| |
| Args: |
| pkgfile: A python file object. |
| |
| Returns the dictionary of key-value pairs that was read from the file. |
| """ |
| d = {} |
| for line in pkgfile: |
| line = line.rstrip('\n') |
| if not line: |
| assert d, 'Packages entry must contain at least one key/value pair' |
| break |
| line = line.split(': ', 1) |
| if len(line) == 2: |
| k, v = line |
| d[k] = v |
| return d |
| |
| def _WritePkgIndex(self, pkgfile, entry): |
| """Write header entry or package entry to packages file. |
| |
| The keys and values will be separated by a colon and a space. The entry |
| will be terminated by a blank line. |
| |
| Args: |
| pkgfile: A python file object. |
| entry: A dictionary of the key/value pairs to write. |
| """ |
| lines = ['%s: %s' % (k, v) for k, v in sorted(entry.items()) if v] |
| pkgfile.write('%s\n\n' % '\n'.join(lines)) |
| |
| def _ReadHeader(self, pkgfile): |
| """Read header of packages file. |
| |
| Args: |
| pkgfile: A python file object. |
| """ |
| assert not self.header, 'Should only read header once.' |
| self.header = self._ReadPkgIndex(pkgfile) |
| |
| def _ReadBody(self, pkgfile): |
| """Read body of packages file. |
| |
| Before calling this function, you must first read the header (using |
| _ReadHeader). |
| |
| Args: |
| pkgfile: A python file object. |
| """ |
| assert self.header, 'Should read header first.' |
| assert not self.packages, 'Should only read body once.' |
| |
| # Read all of the sections in the body by looping until we reach the end |
| # of the file. |
| while True: |
| d = self._ReadPkgIndex(pkgfile) |
| if not d: |
| break |
| if 'CPV' in d: |
| self.packages.append(d) |
| |
| def Read(self, pkgfile): |
| """Read the entire packages file. |
| |
| Args: |
| pkgfile: A python file object. |
| """ |
| self._ReadHeader(pkgfile) |
| self._ReadBody(pkgfile) |
| |
| def RemoveFilteredPackages(self, filter_fn): |
| """Remove packages which match filter_fn. |
| |
| Args: |
| filter_fn: A function which operates on packages. If it returns True, |
| the package should be removed. |
| """ |
| |
| filtered = [p for p in self.packages if not filter_fn(p)] |
| if filtered != self.packages: |
| self.modified = True |
| self.packages = filtered |
| |
| def ResolveDuplicateUploads(self, pkgindexes): |
| """Point packages at files that have already been uploaded. |
| |
| For each package in our index, check if there is an existing package that |
| has already been uploaded to the same base URI. If so, point that package |
| at the existing file, so that we don't have to upload the file. |
| |
| Args: |
| pkgindexes: A list of PackageIndex objects containing info about packages |
| that have already been uploaded. |
| |
| Returns: |
| A list of the packages that still need to be uploaded. |
| """ |
| db = {} |
| for pkgindex in pkgindexes: |
| pkgindex._PopulateDuplicateDB(db) |
| |
| uploads = [] |
| base_uri = self.header['URI'] |
| for pkg in self.packages: |
| sha1 = pkg.get('SHA1') |
| uri = db.get(sha1) |
| if sha1 and uri and uri.startswith(base_uri): |
| pkg['PATH'] = uri[len(base_uri):].lstrip('/') |
| else: |
| uploads.append(pkg) |
| return uploads |
| |
| def SetUploadLocation(self, base_uri, path_prefix): |
| """Set upload location to base_uri + path_prefix. |
| |
| Args: |
| base_uri: Base URI for all packages in the file. We set |
| self.header['URI'] to this value, so all packages must live under |
| this directory. |
| path_prefix: Path prefix to use for all current packages in the file. |
| This will be added to the beginning of the path for every package. |
| """ |
| self.header['URI'] = base_uri |
| for pkg in self.packages: |
| path = pkg['CPV'] + '.tbz2' |
| pkg['PATH'] = '%s/%s' % (path_prefix.rstrip('/'), path) |
| |
| def Write(self, pkgfile): |
| """Write a packages file to disk. |
| |
| If 'modified' flag is set, the TIMESTAMP and PACKAGES fields in the header |
| will be updated before writing to disk. |
| |
| Args: |
| pkgfile: A python file object. |
| """ |
| if self.modified: |
| self.header['TIMESTAMP'] = str(long(time.time())) |
| self.header['PACKAGES'] = str(len(self.packages)) |
| self.modified = False |
| self._WritePkgIndex(pkgfile, self.header) |
| for metadata in sorted(self.packages, key=operator.itemgetter('CPV')): |
| self._WritePkgIndex(pkgfile, metadata) |
| |
| def WriteToNamedTemporaryFile(self): |
| """Write pkgindex to a temporary file. |
| |
| Args: |
| pkgindex: The PackageIndex object. |
| |
| Returns: |
| A temporary file containing the packages from pkgindex. |
| """ |
| f = tempfile.NamedTemporaryFile() |
| self.Write(f) |
| f.flush() |
| f.seek(0) |
| return f |
| |
| |
| def _RetryUrlOpen(url, tries=3): |
| """Open the specified url, retrying if we run into temporary errors. |
| |
| We retry for both network errors and 5xx Server Errors. We do not retry |
| for HTTP errors with a non-5xx code. |
| |
| Args: |
| url: The specified url. |
| tries: The number of times to try. |
| |
| Returns: |
| The result of urllib2.urlopen(url). |
| """ |
| for i in range(tries): |
| try: |
| return urllib2.urlopen(url) |
| except urllib2.HTTPError as e: |
| if i + 1 >= tries or e.code < 500: |
| raise |
| else: |
| print 'Cannot GET %s: %s' % (url, str(e)) |
| except urllib2.URLError as e: |
| if i + 1 >= tries: |
| raise |
| else: |
| print 'Cannot GET %s: %s' % (url, str(e)) |
| print 'Sleeping for 10 seconds before retrying...' |
| time.sleep(10) |
| |
| |
| def GrabRemotePackageIndex(binhost_url): |
| """Grab the latest binary package database from the specified URL. |
| |
| Args: |
| binhost_url: Base URL of remote packages (PORTAGE_BINHOST). |
| |
| Returns: |
| A PackageIndex object, if the Packages file can be retrieved. If the |
| server returns status code 404, None is returned. |
| """ |
| |
| url = '%s/Packages' % binhost_url.rstrip('/') |
| try: |
| f = _RetryUrlOpen(url) |
| except urllib2.HTTPError as e: |
| if e.code == 404: |
| return None |
| raise |
| |
| pkgindex = PackageIndex() |
| pkgindex.Read(f) |
| pkgindex.header.setdefault('URI', binhost_url) |
| f.close() |
| return pkgindex |
| |
| |
| def GrabLocalPackageIndex(package_path): |
| """Read a local packages file from disk into a PackageIndex() object. |
| |
| Args: |
| package_path: Directory containing Packages file. |
| |
| Returns: |
| A PackageIndex object. |
| """ |
| packages_file = file(os.path.join(package_path, 'Packages')) |
| pkgindex = PackageIndex() |
| pkgindex.Read(packages_file) |
| packages_file.close() |
| return pkgindex |