ocrd.processor.base.Processor.input_files() - Code Metrics - Inspection of "resmgr: No downloading on-demand" - OCR-D/core - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — master (#663)

by Konstantin

created 2021-01-27 15:56 UTC

ocrd.processor.base.Processor.input_files() A

↳ Parent: ocrd.processor.base

Complexity

Conditions

Size

Total Lines	21
Code Lines	9

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
eloc	9
dl	0
loc	21
rs	9.95
c	0
b	0
f	0
cc	3
nop	1

"""
Processor base class and helper functions
"""

__all__ = [
    'Processor',
    'generate_processor_help',
    'run_cli',
    'run_processor'
]

from os import makedirs
from os.path import exists, isdir, join
from shutil import copyfileobj
import json
import os
import re
import sys

import requests

from ocrd_utils import (
    VERSION as OCRD_VERSION,
    MIMETYPE_PAGE,
    getLogger,
    initLogging,
    list_resource_candidates,
    list_all_resources,
)
from ocrd_validators import ParameterValidator
from ocrd_models.ocrd_page import MetadataItemType, LabelType, LabelsType
from ..resource_manager import OcrdResourceManager

# XXX imports must remain for backwards-compatibilty
from .helpers import run_cli, run_processor, generate_processor_help # pylint: disable=unused-import

class Processor():
    """
    A processor is an OCR-D compliant command-line-interface for executing
    a single workflow step on the workspace (represented by local METS). It
    reads input files for all or requested physical pages of the input fileGrp(s),
    and writes output files for them into the output fileGrp(s). It may take 
    a number of optional or mandatory parameters.
    """

    def __init__(
            self,
            workspace,
            ocrd_tool=None,
            parameter=None,
            # TODO OCR-D/core#274
            # input_file_grp=None,
            # output_file_grp=None,
            input_file_grp="INPUT",
            output_file_grp="OUTPUT",
            page_id=None,
            show_resource=None,
            list_resources=False,
            show_help=False,
            show_version=False,
            dump_json=False,
            version=None
    ):
        if parameter is None:
            parameter = {}
        if dump_json:
            print(json.dumps(ocrd_tool, indent=True))
            return
        if list_resources:
            for res in list_all_resources(ocrd_tool['executable']):
                print(res)
            return
        if show_resource:
            res_fname = list_resource_candidates(ocrd_tool['executable'], show_resource, is_file=True)
            if not res_fname:
                initLogging()
                logger = getLogger('ocrd.%s.__init__' % ocrd_tool['executable'])
                logger.error("Failed to resolve %s for processort %s" % (show_resource, ocrd_tool['executable']))
            else:
                with open(res_fname[0], 'rb') as f:
                    copyfileobj(f, sys.stdout.buffer)
            return
        self.ocrd_tool = ocrd_tool
        if show_help:
            self.show_help()
            return
        self.version = version
        if show_version:
            self.show_version()
            return
        self.workspace = workspace
        # FIXME HACK would be better to use pushd_popd(self.workspace.directory)
        # but there is no way to do that in process here since it's an
        # overridden method. chdir is almost always an anti-pattern.
        if self.workspace:
            os.chdir(self.workspace.directory)
        self.input_file_grp = input_file_grp
        self.output_file_grp = output_file_grp
        self.page_id = None if page_id == [] or page_id is None else page_id
        parameterValidator = ParameterValidator(ocrd_tool)
        report = parameterValidator.validate(parameter)
        if not report.is_valid:
            raise Exception("Invalid parameters %s" % report.errors)
        self.parameter = parameter

    def show_help(self):
        print(generate_processor_help(self.ocrd_tool, processor_instance=self))

    def show_version(self):
        print("Version %s, ocrd/core %s" % (self.version, OCRD_VERSION))

    def verify(self):
        """
        Verify that the input fulfills the processor's requirements.
        """
        return True

    def process(self):
        """
        Process the workspace
        """
        raise Exception("Must be implemented")


    def add_metadata(self, pcgts):
        """
        Adds PAGE-XML MetadataItem describing the processing step
        """
        pcgts.get_Metadata().add_MetadataItem(
                MetadataItemType(type_="processingStep",
                    name=self.ocrd_tool['steps'][0],
                    value=self.ocrd_tool['executable'],
                    Labels=[LabelsType(
                        externalModel="ocrd-tool",
                        externalId="parameters",
                        Label=[LabelType(type_=name,
                                         value=self.parameter[name])
                               for name in self.parameter.keys()]),
                            LabelsType(
                        externalModel="ocrd-tool",
                        externalId="version",
                        Label=[LabelType(type_=self.ocrd_tool['executable'],
                                         value=self.version),
                               LabelType(type_='ocrd/core',
                                         value=OCRD_VERSION)])
                    ]))

    def resolve_resource(self, val):
        """
        Resolve a resource name to an absolute file path with the algorithm in
        https://ocr-d.de/en/spec/ocrd_tool#file-parameters

        Args:
            val (string): resource value to resolve
        """
        executable = self.ocrd_tool['executable']
        log = getLogger('ocrd.%s.resolve_resource' % executable)
        if exists(val):
            log.debug("Resolved to absolute path %s" % val)
            return val
        ret = [cand for cand in list_resource_candidates(executable, val) if exists(cand)]
        if ret:
            log.debug("Resolved %s to absolute path %s" % (val, ret[0]))
            return ret[0]
        log.error("Could not find resource '%s' for executable '%s'. Try 'ocrd resmgr download %s %s' to download this resource.",
                val, executable, executable, val)
        sys.exit(1)

    def list_all_resources(self):
        """
        List all resources found in the filesystem
        """
        return list_all_resources(self.ocrd_tool['executable'])

    @property
    def input_files(self):
        """
        List the input files (for single input file groups).

        For each physical page:
        - If there is a single PAGE-XML for the page, take it (and forget about all
          other files for that page)
        - Else if there is a single image file, take it (and forget about all other
          files for that page)
        - Otherwise raise an error (complaining that only PAGE-XML warrants
          having multiple images for a single page)
        (https://github.com/cisocrgroup/ocrd_cis/pull/57#issuecomment-656336593)
        """
        if not self.input_file_grp:
            raise ValueError("Processor is missing input fileGrp")
        ret = self.zip_input_files(mimetype=None, on_error='abort')
        if not ret:
            return []
        assert len(ret[0]) == 1, 'Use zip_input_files() instead of input_files when processing multiple input fileGrps'
        return [tuples[0] for tuples in ret]

    def zip_input_files(self, require_first=True, mimetype=None, on_error='skip'):
        """
        List tuples of input files (for multiple input file groups).

        Processors that expect/need multiple input file groups,
        cannot use ``input_files``. They must align (zip) input files
        across pages. This includes the case where not all pages
        are equally present in all file groups. It also requires
        making a consistent selection if there are multiple files
        per page.

        Following the OCR-D functional model, this function tries to
        find a single PAGE file per page, or fall back to a single
        image file per page. In either case, multiple matches per page
        are an error (see error handling below).
        This default behaviour can be changed by using a fixed MIME
        type filter via ``mimetype``. But still, multiple matching
        files per page are an error.

        Single-page multiple-file errors are handled according to
        ``on_error``:
        - if ``skip``, then the page for the respective fileGrp will be
          silently skipped (as if there was no match at all)
        - if ``first``, then the first matching file for the page will be
          silently selected (as if the first was the only match)
        - if ``last``, then the last matching file for the page will be
          silently selected (as if the last was the only match)
        - if ``abort``, then an exception will be raised.
        Multiple matches for PAGE-XML will always raise an exception.

        Args:
             require_first (bool): If true, then skip a page entirely
             whenever it is not available in the first input fileGrp.

             mimetype (str): If not None, filter by the specified MIME
             type (literal or regex prefixed by ``//``.
             Otherwise prefer PAGE or image.
        """
        if not self.input_file_grp:
            raise ValueError("Processor is missing input fileGrp")

        LOG = getLogger('ocrd.processor.base')
        ifgs = self.input_file_grp.split(",")
        # Iterating over all files repeatedly may seem inefficient at first sight,
        # but the unnecessary OcrdFile instantiations for posterior fileGrp filtering
        # can actually be much more costly than traversing the ltree.
        # This might depend on the number of pages vs number of fileGrps.

        pages = dict()
        for i, ifg in enumerate(ifgs):
            for file_ in sorted(self.workspace.mets.find_all_files(
                    pageId=self.page_id, fileGrp=ifg, mimetype=mimetype),
                                # sort by MIME type so PAGE comes before images
                                key=lambda file_: file_.mimetype):
                if not file_.pageId:
                    continue
                ift = pages.setdefault(file_.pageId, [None]*len(ifgs))
                if ift[i]:
                    LOG.debug("another file %s for page %s in input file group %s", file_.ID, file_.pageId, ifg)
                    # fileGrp has multiple files for this page ID
                    if mimetype:
                        # filter was active, this must not happen
                        if on_error == 'skip':

                            ift[i] = None
                        elif on_error == 'first':
                            pass # keep first match
                        elif on_error == 'last':
                            ift[i] = file_
                        elif on_error == 'abort':
                            raise ValueError(
                                "Multiple '%s' matches for page '%s' in fileGrp '%s'." % (
                                    mimetype, file_.pageId, ifg))
                        else:
                            raise Exception("Unknown 'on_error' strategy '%s'" % on_error)
                    elif (ift[i].mimetype == MIMETYPE_PAGE and
                          file_.mimetype != MIMETYPE_PAGE):
                        pass # keep PAGE match
                    elif (ift[i].mimetype == MIMETYPE_PAGE and
                          file_.mimetype == MIMETYPE_PAGE):
                            raise ValueError(
                                "Multiple PAGE-XML matches for page '%s' in fileGrp '%s'." % (
                                    file_.pageId, ifg))
                    else:
                        # filter was inactive but no PAGE is in control, this must not happen
                        if on_error == 'skip':

                            ift[i] = None
                        elif on_error == 'first':
                            pass # keep first match
                        elif on_error == 'last':
                            ift[i] = file_
                        elif on_error == 'abort':
                            raise ValueError(
                                "No PAGE-XML for page '%s' in fileGrp '%s' but multiple matches." % (
                                    file_.pageId, ifg))
                        else:
                            raise Exception("Unknown 'on_error' strategy '%s'" % on_error)
                else:
                    LOG.debug("adding file %s for page %s to input file group %s", file_.ID, file_.pageId, ifg)
                    ift[i] = file_
        ifts = list()
        for page, ifiles in pages.items():
            for i, ifg in enumerate(ifgs):
                if not ifiles[i]:
                    # other fallback options?
                    LOG.error('found no page %s in file group %s',
                              page, ifg)
            if ifiles[0] or not require_first:
                ifts.append(tuple(ifiles))
        return ifts


1		"""
2		Processor base class and helper functions
3		"""
4
5		__all__ = [
6		'Processor',
7		'generate_processor_help',
8		'run_cli',
9		'run_processor'
10		]
11
12		from os import makedirs
13		from os.path import exists, isdir, join
14		from shutil import copyfileobj
15		import json
16		import os
17		import re
18		import sys
19
20		import requests
21
22		from ocrd_utils import (
23		VERSION as OCRD_VERSION,
24		MIMETYPE_PAGE,
25		getLogger,
26		initLogging,
27		list_resource_candidates,
28		list_all_resources,
29		)
30		from ocrd_validators import ParameterValidator
31		from ocrd_models.ocrd_page import MetadataItemType, LabelType, LabelsType
32		from ..resource_manager import OcrdResourceManager
33
34		# XXX imports must remain for backwards-compatibilty
35		from .helpers import run_cli, run_processor, generate_processor_help # pylint: disable=unused-import
36
37		class Processor():
38		"""
39		A processor is an OCR-D compliant command-line-interface for executing
40		a single workflow step on the workspace (represented by local METS). It
41		reads input files for all or requested physical pages of the input fileGrp(s),
42		and writes output files for them into the output fileGrp(s). It may take
43		a number of optional or mandatory parameters.
44		"""
45
46		def __init__(
47		self,
48		workspace,
49		ocrd_tool=None,
50		parameter=None,
51		# TODO OCR-D/core#274
52		# input_file_grp=None,
53		# output_file_grp=None,
54		input_file_grp="INPUT",
55		output_file_grp="OUTPUT",
56		page_id=None,
57		show_resource=None,
58		list_resources=False,
59		show_help=False,
60		show_version=False,
61		dump_json=False,
62		version=None
63		):
64		if parameter is None:
65		parameter = {}
66		if dump_json:
67		print(json.dumps(ocrd_tool, indent=True))
68		return
69		if list_resources:
70		for res in list_all_resources(ocrd_tool['executable']):
71		print(res)
72		return
73		if show_resource:
74		res_fname = list_resource_candidates(ocrd_tool['executable'], show_resource, is_file=True)
75		if not res_fname:
76		initLogging()
77		logger = getLogger('ocrd.%s.__init__' % ocrd_tool['executable'])
78		logger.error("Failed to resolve %s for processort %s" % (show_resource, ocrd_tool['executable']))
79		else:
80		with open(res_fname[0], 'rb') as f:
81		copyfileobj(f, sys.stdout.buffer)
82		return
83		self.ocrd_tool = ocrd_tool
84		if show_help:
85		self.show_help()
86		return
87		self.version = version
88		if show_version:
89		self.show_version()
90		return
91		self.workspace = workspace
92		# FIXME HACK would be better to use pushd_popd(self.workspace.directory)
93		# but there is no way to do that in process here since it's an
94		# overridden method. chdir is almost always an anti-pattern.
95		if self.workspace:
96		os.chdir(self.workspace.directory)
97		self.input_file_grp = input_file_grp
98		self.output_file_grp = output_file_grp
99		self.page_id = None if page_id == [] or page_id is None else page_id
100		parameterValidator = ParameterValidator(ocrd_tool)
101		report = parameterValidator.validate(parameter)
102		if not report.is_valid:
103		raise Exception("Invalid parameters %s" % report.errors)
104		self.parameter = parameter
105
106		def show_help(self):
107		print(generate_processor_help(self.ocrd_tool, processor_instance=self))
108
109		def show_version(self):
110		print("Version %s, ocrd/core %s" % (self.version, OCRD_VERSION))
111
112		def verify(self):
113		"""
114		Verify that the input fulfills the processor's requirements.
115		"""
116		return True
117
118		def process(self):
119		"""
120		Process the workspace
121		"""
122		raise Exception("Must be implemented")
123
124
125		def add_metadata(self, pcgts):
126		"""
127		Adds PAGE-XML MetadataItem describing the processing step
128		"""
129		pcgts.get_Metadata().add_MetadataItem(
130		MetadataItemType(type_="processingStep",
131		name=self.ocrd_tool['steps'][0],
132		value=self.ocrd_tool['executable'],
133		Labels=[LabelsType(
134		externalModel="ocrd-tool",
135		externalId="parameters",
136		Label=[LabelType(type_=name,
137		value=self.parameter[name])
138		for name in self.parameter.keys()]),
139		LabelsType(
140		externalModel="ocrd-tool",
141		externalId="version",
142		Label=[LabelType(type_=self.ocrd_tool['executable'],
143		value=self.version),
144		LabelType(type_='ocrd/core',
145		value=OCRD_VERSION)])
146		]))
147
148		def resolve_resource(self, val):
149		"""
150		Resolve a resource name to an absolute file path with the algorithm in
151		https://ocr-d.de/en/spec/ocrd_tool#file-parameters
152
153		Args:
154		val (string): resource value to resolve
155		"""
156		executable = self.ocrd_tool['executable']
157		log = getLogger('ocrd.%s.resolve_resource' % executable)
158		if exists(val):
159		log.debug("Resolved to absolute path %s" % val)
160		return val
161		ret = [cand for cand in list_resource_candidates(executable, val) if exists(cand)]
162		if ret:
163		log.debug("Resolved %s to absolute path %s" % (val, ret[0]))
164		return ret[0]
165		log.error("Could not find resource '%s' for executable '%s'. Try 'ocrd resmgr download %s %s' to download this resource.",
166		val, executable, executable, val)
167		sys.exit(1)
168
169		def list_all_resources(self):
170		"""
171		List all resources found in the filesystem
172		"""
173		return list_all_resources(self.ocrd_tool['executable'])
174
175		@property
176		def input_files(self):
177		"""
178		List the input files (for single input file groups).
179
180		For each physical page:
181		- If there is a single PAGE-XML for the page, take it (and forget about all
182		other files for that page)
183		- Else if there is a single image file, take it (and forget about all other
184		files for that page)
185		- Otherwise raise an error (complaining that only PAGE-XML warrants
186		having multiple images for a single page)
187		(https://github.com/cisocrgroup/ocrd_cis/pull/57#issuecomment-656336593)
188		"""
189		if not self.input_file_grp:
190		raise ValueError("Processor is missing input fileGrp")
191		ret = self.zip_input_files(mimetype=None, on_error='abort')
192		if not ret:
193		return []
194		assert len(ret[0]) == 1, 'Use zip_input_files() instead of input_files when processing multiple input fileGrps'
195		return [tuples[0] for tuples in ret]
196
197		def zip_input_files(self, require_first=True, mimetype=None, on_error='skip'):
198		"""
199		List tuples of input files (for multiple input file groups).
200
201		Processors that expect/need multiple input file groups,
202		cannot use ``input_files``. They must align (zip) input files
203		across pages. This includes the case where not all pages
204		are equally present in all file groups. It also requires
205		making a consistent selection if there are multiple files
206		per page.
207
208		Following the OCR-D functional model, this function tries to
209		find a single PAGE file per page, or fall back to a single
210		image file per page. In either case, multiple matches per page
211		are an error (see error handling below).
212		This default behaviour can be changed by using a fixed MIME
213		type filter via ``mimetype``. But still, multiple matching
214		files per page are an error.
215
216		Single-page multiple-file errors are handled according to
217		``on_error``:
218		- if ``skip``, then the page for the respective fileGrp will be
219		silently skipped (as if there was no match at all)
220		- if ``first``, then the first matching file for the page will be
221		silently selected (as if the first was the only match)
222		- if ``last``, then the last matching file for the page will be
223		silently selected (as if the last was the only match)
224		- if ``abort``, then an exception will be raised.
225		Multiple matches for PAGE-XML will always raise an exception.
226
227		Args:
228		require_first (bool): If true, then skip a page entirely
229		whenever it is not available in the first input fileGrp.
230
231		mimetype (str): If not None, filter by the specified MIME
232		type (literal or regex prefixed by ``//``.
233		Otherwise prefer PAGE or image.
234		"""
235		if not self.input_file_grp:
236		raise ValueError("Processor is missing input fileGrp")
237
238		LOG = getLogger('ocrd.processor.base')
239		ifgs = self.input_file_grp.split(",")
240		# Iterating over all files repeatedly may seem inefficient at first sight,
241		# but the unnecessary OcrdFile instantiations for posterior fileGrp filtering
242		# can actually be much more costly than traversing the ltree.
243		# This might depend on the number of pages vs number of fileGrps.
244
245		pages = dict()
246		for i, ifg in enumerate(ifgs):
247		for file_ in sorted(self.workspace.mets.find_all_files(
248		pageId=self.page_id, fileGrp=ifg, mimetype=mimetype),
249		# sort by MIME type so PAGE comes before images
250		key=lambda file_: file_.mimetype):
251		if not file_.pageId:
252		continue
253		ift = pages.setdefault(file_.pageId, [None]*len(ifgs))
254		if ift[i]:
255		LOG.debug("another file %s for page %s in input file group %s", file_.ID, file_.pageId, ifg)
256		# fileGrp has multiple files for this page ID
257		if mimetype:
258		# filter was active, this must not happen
259	View Code Duplication	if on_error == 'skip':
		0 ignored issues – show Duplication introduced 2020-11-02 16:44 UTC by Report Bug Copy Issue Report This code seems to be duplicated in your project. Loading history...
260		ift[i] = None
261		elif on_error == 'first':
262		pass # keep first match
263		elif on_error == 'last':
264		ift[i] = file_
265		elif on_error == 'abort':
266		raise ValueError(
267		"Multiple '%s' matches for page '%s' in fileGrp '%s'." % (
268		mimetype, file_.pageId, ifg))
269		else:
270		raise Exception("Unknown 'on_error' strategy '%s'" % on_error)
271		elif (ift[i].mimetype == MIMETYPE_PAGE and
272		file_.mimetype != MIMETYPE_PAGE):
273		pass # keep PAGE match
274		elif (ift[i].mimetype == MIMETYPE_PAGE and
275		file_.mimetype == MIMETYPE_PAGE):
276		raise ValueError(
277		"Multiple PAGE-XML matches for page '%s' in fileGrp '%s'." % (
278		file_.pageId, ifg))
279		else:
280		# filter was inactive but no PAGE is in control, this must not happen
281	View Code Duplication	if on_error == 'skip':
		0 ignored issues – show Duplication introduced 2020-11-02 16:44 UTC by Report Bug Copy Issue Report This code seems to be duplicated in your project. Loading history...
282		ift[i] = None
283		elif on_error == 'first':
284		pass # keep first match
285		elif on_error == 'last':
286		ift[i] = file_
287		elif on_error == 'abort':
288		raise ValueError(
289		"No PAGE-XML for page '%s' in fileGrp '%s' but multiple matches." % (
290		file_.pageId, ifg))
291		else:
292		raise Exception("Unknown 'on_error' strategy '%s'" % on_error)
293		else:
294		LOG.debug("adding file %s for page %s to input file group %s", file_.ID, file_.pageId, ifg)
295		ift[i] = file_
296		ifts = list()
297		for page, ifiles in pages.items():
298		for i, ifg in enumerate(ifgs):
299		if not ifiles[i]:
300		# other fallback options?
301		LOG.error('found no page %s in file group %s',
302		page, ifg)
303		if ifiles[0] or not require_first:
304		ifts.append(tuple(ifiles))
305		return ifts
306

OCR-D / core

Pull Request — master (#663)

ocrd.processor.base.Processor.input_files() A

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like