path: root/tools/rebaseline_imagefiles.py

#!/usr/bin/python

'''
Copyright 2013 Google Inc.

Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
'''

'''
Rebaselines GM test results as individual image files
(the "old way", before https://goto.google.com/ChecksumTransitionDetail ).

Once we have switched our expectations to JSON form for all platforms,
we can delete this file.

There is a lot of code duplicated between here and rebaseline.py, but
that's fine because we will delete this file soon.

TODO(epoger): Fix indentation in this file (2-space indents, not 4-space).
'''

# System-level imports
import os
import re
import subprocess
import sys
import urllib2

# Imports from within Skia
#
# We need to add the 'gm' directory, so that we can import gm_json.py within
# that directory.  That script allows us to parse the actual-results.json file
# written out by the GM tool.
# Make sure that the 'gm' dir is in the PYTHONPATH, but add it at the *end*
# so any dirs that are already in the PYTHONPATH will be preferred.
#
# This assumes that the 'gm' directory has been checked out as a sibling of
# the 'tools' directory containing this script, which will be the case if
# 'trunk' was checked out as a single unit.
GM_DIRECTORY = os.path.realpath(
    os.path.join(os.path.dirname(os.path.dirname(__file__)), 'gm'))
if GM_DIRECTORY not in sys.path:
    sys.path.append(GM_DIRECTORY)
import gm_json


class CommandFailedException(Exception):
    pass

class ImageRebaseliner(object):

    # params:
    #  expectations_root: root directory of all expectations
    #  json_base_url: base URL from which to read json_filename
    #  json_filename: filename (under json_base_url) from which to read a
    #                 summary of results; typically "actual-results.json"
    #  exception_handler: reference to rebaseline.ExceptionHandler object
    #  tests: list of tests to rebaseline, or None if we should rebaseline
    #         whatever files the JSON results summary file tells us to
    #  configs: which configs to run for each test, or None if we should
    #           rebaseline whatever configs the JSON results summary file tells
    #           us to
    #  dry_run: if True, instead of actually downloading files or adding
    #           files to checkout, display a list of operations that
    #           we would normally perform
    #  add_new: if True, add expectations for tests which don't have any yet
    #  missing_json_is_fatal: whether to halt execution if we cannot read a
    #                         JSON actual result summary file
    def __init__(self, expectations_root, json_base_url, json_filename,
                 exception_handler, tests=None, configs=None, dry_run=False,
                 add_new=False, missing_json_is_fatal=False):
        self._expectations_root = expectations_root
        self._tests = tests
        self._configs = configs
        self._json_base_url = json_base_url
        self._json_filename = json_filename
        self._exception_handler = exception_handler
        self._dry_run = dry_run
        self._add_new = add_new
        self._missing_json_is_fatal = missing_json_is_fatal
        self._image_filename_re = re.compile(gm_json.IMAGE_FILENAME_PATTERN)
        self._is_svn_checkout = (
            os.path.exists(os.path.join(expectations_root, '.svn')) or
            os.path.exists(os.path.join(expectations_root, os.pardir, '.svn')))
        self._is_git_checkout = (
            os.path.exists(os.path.join(expectations_root, '.git')) or
            os.path.exists(os.path.join(expectations_root, os.pardir, '.git')))

    # If dry_run is False, execute subprocess.call(cmd).
    # If dry_run is True, print the command we would have otherwise run.
    # Raises a CommandFailedException if the command fails.
    def _Call(self, cmd):
        if self._dry_run:
            print '%s' % ' '.join(cmd)
            return
        if subprocess.call(cmd) != 0:
            raise CommandFailedException('error running command: ' +
                                         ' '.join(cmd))

    # Download a single actual result from GoogleStorage.
    # Raises an exception if it fails.
    def _DownloadFromGoogleStorage(self, infilename, outfilename, all_results):
        test_name = self._image_filename_re.match(infilename).group(1)
        if not test_name:
            raise Exception('unable to find test_name for infilename %s' %
                            infilename)
        try:
            hash_type, hash_value = all_results[infilename]
        except KeyError:
            raise Exception('unable to find filename %s in all_results dict' %
                            infilename)
        except ValueError as e:
            raise Exception(
                'ValueError reading filename %s from all_results dict: %s' % (
                    infilename, e))
        url = gm_json.CreateGmActualUrl(
            test_name=test_name, hash_type=hash_type, hash_digest=hash_value)
        try:
            self._DownloadFile(source_url=url, dest_filename=outfilename)
        except CommandFailedException:
            raise Exception('Couldn\'t fetch gs_url %s as outfile %s' % (
                url, outfilename))

    # Download a single file, raising a CommandFailedException if it fails.
    def _DownloadFile(self, source_url, dest_filename):
        # Download into a temporary file and then rename it afterwards,
        # so that we don't corrupt the existing file if it fails midway thru.
        temp_filename = os.path.join(os.path.dirname(dest_filename),
                                     '.temp-' + os.path.basename(dest_filename))

        # TODO(epoger): Replace calls to "curl"/"mv" (which will only work on
        # Unix) with a Python HTTP library (which should work cross-platform)
        self._Call([ 'curl', '--fail', '--silent', source_url,
                     '--output', temp_filename ])
        self._Call([ 'mv', temp_filename, dest_filename ])

    # Returns the full contents of a URL, as a single string.
    #
    # Unlike standard URL handling, we allow relative "file:" URLs;
    # for example, "file:one/two" resolves to the file ./one/two
    # (relative to current working dir)
    def _GetContentsOfUrl(self, url):
        file_prefix = 'file:'
        if url.startswith(file_prefix):
            filename = url[len(file_prefix):]
            return open(filename, 'r').read()
        else:
            return urllib2.urlopen(url).read()

    # Returns a dictionary of actual results from actual-results.json file.
    #
    # The dictionary returned has this format:
    # {
    #  u'imageblur_565.png': [u'bitmap-64bitMD5', 3359963596899141322],
    #  u'imageblur_8888.png': [u'bitmap-64bitMD5', 4217923806027861152],
    #  u'shadertext3_8888.png': [u'bitmap-64bitMD5', 3713708307125704716]
    # }
    #
    # If the JSON actual result summary file cannot be loaded, the behavior
    # depends on self._missing_json_is_fatal:
    # - if true: execution will halt with an exception
    # - if false: we will log an error message but return an empty dictionary
    #
    # params:
    #  json_url: URL pointing to a JSON actual result summary file
    #  sections: a list of section names to include in the results, e.g.
    #            [gm_json.JSONKEY_ACTUALRESULTS_FAILED,
    #             gm_json.JSONKEY_ACTUALRESULTS_NOCOMPARISON] ;
    #            if None, then include ALL sections.
    def _GetActualResults(self, json_url, sections=None):
        try:
            json_contents = self._GetContentsOfUrl(json_url)
        except (urllib2.HTTPError, IOError):
            message = 'unable to load JSON summary URL %s' % json_url
            if self._missing_json_is_fatal:
                raise ValueError(message)
            else:
                print '# %s' % message
                return {}

        json_dict = gm_json.LoadFromString(json_contents)
        results_to_return = {}
        actual_results = json_dict[gm_json.JSONKEY_ACTUALRESULTS]
        if not sections:
            sections = actual_results.keys()
        for section in sections:
            section_results = actual_results[section]
            if section_results:
                results_to_return.update(section_results)
        return results_to_return

    # Returns a list of files that require rebaselining.
    #
    # Note that this returns a list of FILES, like this:
    #  ['imageblur_565.png', 'xfermodes_pdf.png']
    # rather than a list of TESTS, like this:
    #  ['imageblur', 'xfermodes']
    #
    # params:
    #  json_url: URL pointing to a JSON actual result summary file
    #  add_new: if True, then return files listed in any of these sections:
    #            - JSONKEY_ACTUALRESULTS_FAILED
    #            - JSONKEY_ACTUALRESULTS_NOCOMPARISON
    #           if False, then return files listed in these sections:
    #            - JSONKEY_ACTUALRESULTS_FAILED
    #
    def _GetFilesToRebaseline(self, json_url, add_new):
        if self._dry_run:
            print ''
            print '#'
        print ('# Getting files to rebaseline from JSON summary URL %s ...'
               % json_url)
        sections = [gm_json.JSONKEY_ACTUALRESULTS_FAILED]
        if add_new:
            sections.append(gm_json.JSONKEY_ACTUALRESULTS_NOCOMPARISON)
        results_to_rebaseline = self._GetActualResults(json_url=json_url,
                                                       sections=sections)
        files_to_rebaseline = results_to_rebaseline.keys()
        files_to_rebaseline.sort()
        print '# ... found files_to_rebaseline %s' % files_to_rebaseline
        if self._dry_run:
            print '#'
        return files_to_rebaseline

    # Rebaseline a single file.
    def _RebaselineOneFile(self, expectations_subdir, builder_name,
                           infilename, outfilename, all_results):
        if self._dry_run:
            print ''
        print '# ' + infilename

        # Download this result image from Google Storage.
        # If it fails, an exception will be raised.
        self._DownloadFromGoogleStorage(infilename=infilename,
                                        outfilename=outfilename,
                                        all_results=all_results)

        # Add this file to version control (if appropriate).
        if self._add_new:
            if self._is_svn_checkout:
                cmd = [ 'svn', 'add', '--quiet', outfilename ]
                self._Call(cmd)
                cmd = [ 'svn', 'propset', '--quiet', 'svn:mime-type',
                        'image/png', outfilename ];
                self._Call(cmd)
            elif self._is_git_checkout:
                cmd = [ 'git', 'add', outfilename ]
                self._Call(cmd)

    # Rebaseline all tests/types we specified in the constructor,
    # within this gm-expectations subdir.
    #
    # params:
    #  subdir : e.g. 'base-shuttle-win7-intel-float'
    #  builder : e.g. 'Test-Win7-ShuttleA-HD2000-x86-Release'
    def RebaselineSubdir(self, subdir, builder):
        if not os.path.isdir(os.path.join(self._expectations_root, subdir)):
            self._exception_handler.RaiseExceptionOrContinue(Exception((
                'Could not find "%s" subdir within expectations_root "%s".  ' +
                'Are you sure --expectations-root is pointing at a valid ' +
                'gm-expected directory?') % (subdir, self._expectations_root)))
            return

        json_url = '/'.join([self._json_base_url,
                             subdir, builder, subdir,
                             self._json_filename])
        all_results = self._GetActualResults(json_url=json_url)
        filenames = self._GetFilesToRebaseline(json_url=json_url,
                                               add_new=self._add_new)
        skipped_files = []
        for filename in filenames:
            (test, config) = self._image_filename_re.match(filename).groups()
            if self._tests:
                if test not in self._tests:
                    skipped_files.append(filename)
                    continue
            if self._configs:
                if config not in self._configs:
                    skipped_files.append(filename)
                    continue
            outfilename = os.path.join(self._expectations_root, subdir,
                                       filename);
            try:
                self._RebaselineOneFile(expectations_subdir=subdir,
                                        builder_name=builder,
                                        infilename=filename,
                                        outfilename=outfilename,
                                        all_results=all_results)
            except BaseException as e:
                self._exception_handler.RaiseExceptionOrContinue(e)