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1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 | #!/usr/bin/python2.5 # # Copyright 2007 Google Inc. All Rights Reserved. # # Licensed 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. """A tool for merging two Google Transit feeds. Given two Google Transit feeds intending to cover two disjoint calendar intervals, this tool will attempt to produce a single feed by merging as much of the two feeds together as possible. For example, most stops remain the same throughout the year. Therefore, many of the stops given in stops.txt for the first feed represent the same stops given in the second feed. This tool will try to merge these stops so they only appear once in the resultant feed. A note on terminology: The first schedule is referred to as the "old" schedule; the second as the "new" schedule. The resultant schedule is referred to as the "merged" schedule. Names of things in the old schedule are variations of the letter "a" while names of things from the new schedule are variations of "b". The objects that represents routes, agencies and so on are called "entities". usage: merge.py [options] old_feed_path new_feed_path merged_feed_path Run merge.py --help for a list of the possible options. """ __author__ = 'timothy.stranex@gmail.com (Timothy Stranex)' import datetime import optparse import os import re import sys import time import transitfeed from transitfeed import util import webbrowser # TODO: # 1. write unit tests that use actual data # 2. write a proper trip and stop_times merger # 3. add a serialised access method for stop_times and shapes to transitfeed # 4. add support for merging schedules which have some service period overlap def ApproximateDistanceBetweenPoints(pa, pb): """Finds the distance between two points on the Earth's surface. This is an approximate distance based on assuming that the Earth is a sphere. The points are specified by their lattitude and longitude. Args: pa: the first (lat, lon) point tuple pb: the second (lat, lon) point tuple Returns: The distance as a float in metres. """ alat, alon = pa blat, blon = pb sa = transitfeed.Stop(lat=alat, lng=alon) sb = transitfeed.Stop(lat=blat, lng=blon) return transitfeed.ApproximateDistanceBetweenStops(sa, sb) class Error(Exception): """The base exception class for this module.""" class MergeError(Error): """An error produced when two entities could not be merged.""" class MergeProblemWithContext(transitfeed.ExceptionWithContext): """The base exception class for problem reporting in the merge module. Attributes: dataset_merger: The DataSetMerger that generated this problem. entity_type_name: The entity type of the dataset_merger. This is just dataset_merger.ENTITY_TYPE_NAME. ERROR_TEXT: The text used for generating the problem message. """ def __init__(self, dataset_merger, problem_type=transitfeed.TYPE_WARNING, **kwargs): """Initialise the exception object. Args: dataset_merger: The DataSetMerger instance that generated this problem. problem_type: The problem severity. This should be set to one of the corresponding constants in transitfeed. kwargs: Keyword arguments to be saved as instance attributes. """ kwargs['type'] = problem_type kwargs['entity_type_name'] = dataset_merger.ENTITY_TYPE_NAME transitfeed.ExceptionWithContext.__init__(self, None, None, **kwargs) self.dataset_merger = dataset_merger def FormatContext(self): return "In files '%s'" % self.dataset_merger.FILE_NAME class SameIdButNotMerged(MergeProblemWithContext): ERROR_TEXT = ("There is a %(entity_type_name)s in the old feed with id " "'%(id)s' and one from the new feed with the same id but " "they could not be merged:") class CalendarsNotDisjoint(MergeProblemWithContext): ERROR_TEXT = ("The service periods could not be merged since they are not " "disjoint.") class MergeNotImplemented(MergeProblemWithContext): ERROR_TEXT = ("The feed merger does not currently support merging in this " "file. The entries have been duplicated instead.") class FareRulesBroken(MergeProblemWithContext): ERROR_TEXT = ("The feed merger is currently unable to handle fare rules " "properly.") class MergeProblemReporterBase(transitfeed.ProblemReporterBase): """The base problem reporter class for the merge module.""" def SameIdButNotMerged(self, dataset, entity_id, reason): self._Report(SameIdButNotMerged(dataset, id=entity_id, reason=reason)) def CalendarsNotDisjoint(self, dataset): self._Report(CalendarsNotDisjoint(dataset, problem_type=transitfeed.TYPE_ERROR)) def MergeNotImplemented(self, dataset): self._Report(MergeNotImplemented(dataset)) def FareRulesBroken(self, dataset): self._Report(FareRulesBroken(dataset)) class ExceptionProblemReporter(MergeProblemReporterBase): """A problem reporter that reports errors by raising exceptions.""" def __init__(self, raise_warnings=False): """Initialise. Args: raise_warnings: If this is True then warnings are also raised as exceptions. """ MergeProblemReporterBase.__init__(self) self._raise_warnings = raise_warnings def _Report(self, merge_problem): if self._raise_warnings or merge_problem.IsError(): raise merge_problem class HTMLProblemReporter(MergeProblemReporterBase): """A problem reporter which generates HTML output.""" def __init__(self): """Initialise.""" MergeProblemReporterBase.__init__(self) self._dataset_warnings = {} # a map from DataSetMergers to their warnings self._dataset_errors = {} self._warning_count = 0 self._error_count = 0 def _Report(self, merge_problem): if merge_problem.IsWarning(): dataset_problems = self._dataset_warnings self._warning_count += 1 else: dataset_problems = self._dataset_errors self._error_count += 1 problem_html = '<li>%s</li>' % ( merge_problem.FormatProblem().replace('\n', '<br>')) dataset_problems.setdefault(merge_problem.dataset_merger, []).append( problem_html) def _GenerateStatsTable(self, feed_merger): """Generate an HTML table of merge statistics. Args: feed_merger: The FeedMerger instance. Returns: The generated HTML as a string. """ rows = [] rows.append('<tr><th class="header"/><th class="header">Merged</th>' '<th class="header">Copied from old feed</th>' '<th class="header">Copied from new feed</th></tr>') for merger in feed_merger.GetMergerList(): stats = merger.GetMergeStats() if stats is None: continue merged, not_merged_a, not_merged_b = stats rows.append('<tr><th class="header">%s</th>' '<td class="header">%d</td>' '<td class="header">%d</td>' '<td class="header">%d</td></tr>' % (merger.DATASET_NAME, merged, not_merged_a, not_merged_b)) return '<table>%s</table>' % '\n'.join(rows) def _GenerateSection(self, problem_type): """Generate a listing of the given type of problems. Args: problem_type: The type of problem. This is one of the problem type constants from transitfeed. Returns: The generated HTML as a string. """ if problem_type == transitfeed.TYPE_WARNING: dataset_problems = self._dataset_warnings heading = 'Warnings' else: dataset_problems = self._dataset_errors heading = 'Errors' if not dataset_problems: return '' prefix = '<h2 class="issueHeader">%s:</h2>' % heading dataset_sections = [] for dataset_merger, problems in dataset_problems.items(): dataset_sections.append('<h3>%s</h3><ol>%s</ol>' % ( dataset_merger.FILE_NAME, '\n'.join(problems))) body = '\n'.join(dataset_sections) return prefix + body def _GenerateSummary(self): """Generate a summary of the warnings and errors. Returns: The generated HTML as a string. """ items = [] if self._dataset_errors: items.append('errors: %d' % self._error_count) if self._dataset_warnings: items.append('warnings: %d' % self._warning_count) if items: return '<p><span class="fail">%s</span></p>' % '<br>'.join(items) else: return '<p><span class="pass">feeds merged successfully</span></p>' def WriteOutput(self, output_file, feed_merger, old_feed_path, new_feed_path, merged_feed_path): """Write the HTML output to a file. Args: output_file: The file object that the HTML output will be written to. feed_merger: The FeedMerger instance. old_feed_path: The path to the old feed file as a string. new_feed_path: The path to the new feed file as a string merged_feed_path: The path to the merged feed file as a string. This may be None if no merged feed was written. """ if merged_feed_path is None: html_merged_feed_path = '' else: html_merged_feed_path = '<p>Merged feed created: <code>%s</code></p>' % ( merged_feed_path) html_header = """<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> <title>Feed Merger Results</title> <style> body {font-family: Georgia, serif; background-color: white} .path {color: gray} div.problem {max-width: 500px} td,th {background-color: khaki; padding: 2px; font-family:monospace} td.problem,th.problem {background-color: dc143c; color: white; padding: 2px; font-family:monospace} table {border-spacing: 5px 0px; margin-top: 3px} h3.issueHeader {padding-left: 1em} span.pass {background-color: lightgreen} span.fail {background-color: yellow} .pass, .fail {font-size: 16pt; padding: 3px} ol,.unused {padding-left: 40pt} .header {background-color: white; font-family: Georgia, serif; padding: 0px} th.header {text-align: right; font-weight: normal; color: gray} .footer {font-size: 10pt} </style> </head> <body> <h1>Feed merger results</h1> <p>Old feed: <code>%(old_feed_path)s</code></p> <p>New feed: <code>%(new_feed_path)s</code></p> %(html_merged_feed_path)s""" % locals() html_stats = self._GenerateStatsTable(feed_merger) html_summary = self._GenerateSummary() html_errors = self._GenerateSection(transitfeed.TYPE_ERROR) html_warnings = self._GenerateSection(transitfeed.TYPE_WARNING) html_footer = """ <div class="footer"> Generated using transitfeed version %s on %s. </div> </body> </html>""" % (transitfeed.__version__, time.strftime('%B %d, %Y at %I:%M %p %Z')) output_file.write(transitfeed.EncodeUnicode(html_header)) output_file.write(transitfeed.EncodeUnicode(html_stats)) output_file.write(transitfeed.EncodeUnicode(html_summary)) output_file.write(transitfeed.EncodeUnicode(html_errors)) output_file.write(transitfeed.EncodeUnicode(html_warnings)) output_file.write(transitfeed.EncodeUnicode(html_footer)) class ConsoleWarningRaiseErrorProblemReporter(transitfeed.ProblemReporterBase): """Problem reporter to use when loading feeds for merge.""" def _Report(self, e): if e.IsError(): raise e else: print transitfeed.EncodeUnicode(e.FormatProblem()) context = e.FormatContext() if context: print context def LoadWithoutErrors(path, memory_db): """"Return a Schedule object loaded from path; sys.exit for any error.""" loading_problem_handler = ConsoleWarningRaiseErrorProblemReporter() try: schedule = transitfeed.Loader(path, memory_db=memory_db, problems=loading_problem_handler).Load() except transitfeed.ExceptionWithContext, e: print >>sys.stderr, ( "\n\nFeeds to merge must load without any errors.\n" "While loading %s the following error was found:\n%s\n%s\n" % (path, e.FormatContext(), transitfeed.EncodeUnicode(e.FormatProblem()))) sys.exit(1) return schedule class DataSetMerger(object): """A DataSetMerger is in charge of merging a set of entities. This is an abstract class and should be subclassed for each different entity type. Attributes: ENTITY_TYPE_NAME: The name of the entity type like 'agency' or 'stop'. FILE_NAME: The name of the file containing this data set like 'agency.txt'. DATASET_NAME: A name for the dataset like 'Agencies' or 'Stops'. """ def __init__(self, feed_merger): """Initialise. Args: feed_merger: The FeedMerger. """ self.feed_merger = feed_merger self._num_merged = 0 self._num_not_merged_a = 0 self._num_not_merged_b = 0 def _MergeIdentical(self, a, b): """Tries to merge two values. The values are required to be identical. Args: a: The first value. b: The second value. Returns: The trivially merged value. Raises: MergeError: The values were not identical. """ if a != b: raise MergeError("values must be identical ('%s' vs '%s')" % (transitfeed.EncodeUnicode(a), transitfeed.EncodeUnicode(b))) return b def _MergeIdenticalCaseInsensitive(self, a, b): """Tries to merge two strings. The string are required to be the same ignoring case. The second string is always used as the merged value. Args: a: The first string. b: The second string. Returns: The merged string. This is equal to the second string. Raises: MergeError: The strings were not the same ignoring case. """ if a.lower() != b.lower(): raise MergeError("values must be the same (case insensitive) " "('%s' vs '%s')" % (transitfeed.EncodeUnicode(a), transitfeed.EncodeUnicode(b))) return b def _MergeOptional(self, a, b): """Tries to merge two values which may be None. If both values are not None, they are required to be the same and the merge is trivial. If one of the values is None and the other is not None, the merge results in the one which is not None. If both are None, the merge results in None. Args: a: The first value. b: The second value. Returns: The merged value. Raises: MergeError: If both values are not None and are not the same. """ if a and b: if a != b: raise MergeError("values must be identical if both specified " "('%s' vs '%s')" % (transitfeed.EncodeUnicode(a), transitfeed.EncodeUnicode(b))) return a or b def _MergeSameAgency(self, a_agency_id, b_agency_id): """Merge agency ids to the corresponding agency id in the merged schedule. Args: a_agency_id: an agency id from the old schedule b_agency_id: an agency id from the new schedule Returns: The agency id of the corresponding merged agency. Raises: MergeError: If a_agency_id and b_agency_id do not correspond to the same merged agency. KeyError: Either aaid or baid is not a valid agency id. """ a_agency_id = (a_agency_id or self.feed_merger.a_schedule.GetDefaultAgency().agency_id) b_agency_id = (b_agency_id or self.feed_merger.b_schedule.GetDefaultAgency().agency_id) a_agency = self.feed_merger.a_merge_map[ self.feed_merger.a_schedule.GetAgency(a_agency_id)] b_agency = self.feed_merger.b_merge_map[ self.feed_merger.b_schedule.GetAgency(b_agency_id)] if a_agency != b_agency: raise MergeError('agency must be the same') return a_agency.agency_id def _SchemedMerge(self, scheme, a, b): """Tries to merge two entities according to a merge scheme. A scheme is specified by a map where the keys are entity attributes and the values are merge functions like Merger._MergeIdentical or Merger._MergeOptional. The entity is first migrated to the merged schedule. Then the attributes are individually merged as specified by the scheme. Args: scheme: The merge scheme, a map from entity attributes to merge functions. a: The entity from the old schedule. b: The entity from the new schedule. Returns: The migrated and merged entity. Raises: MergeError: One of the attributes was not able to be merged. """ migrated = self._Migrate(b, self.feed_merger.b_schedule, False) for attr, merger in scheme.items(): a_attr = getattr(a, attr, None) b_attr = getattr(b, attr, None) try: merged_attr = merger(< |