def pdf2pdfa(task, input_file_path, output_file_path,
language='eng', output_types=['pdf'], logger=None, timeout=600):
"""
Convert scanned PDF into searchable PDF-A or optionally into hOCR or txt (see output_types)
:param task: Task
:param input_file_path:
:param output_file_path:
:param language:
:param output_types: List['pdf', 'hocr', 'txt']
:param logger: ProcessLogger
:param timeout: sec
:return:
"""
with tempfile.TemporaryDirectory() as tmp_dir:
pdf2image_kwargs = dict(fmt='jpg', jpegopt={'quality': 50})
img_list_file_path = pdf2img(input_file_path, work_dir=tmp_dir, **pdf2image_kwargs)
cmd_args = ['tesseract', '-l', str(language), img_list_file_path, output_file_path]
for ot in output_types:
cmd_args += ['-c', f'tessedit_create_{ot}=1']
def err(line):
logger.info(f'tesseract converting {img_list_file_path} '
f'images into {output_file_path}:\n{line}')
read_output(cmd_args, stderr_callback=err, timeout_sec=timeout, task=task) or ''
# rename file.pdf.alt.pdf into file.pdf.alt
for ot in output_types:
os.rename(output_file_path + f'.{ot}', output_file_path)
def parse_file_local(self,
local_path: str,
original_file_name: str,
timeout: int = 60,
encoding_name: str = 'utf-8',
logger: ProcessLogger = None,
enable_ocr: bool = True) -> Dict:
mode_flag = self.TIKA_MODE_OCR if enable_ocr else self.TIKA_MODE_PDF_ONLY
os.environ[self.TIKA_ENV_VAR_FLAG_MODE] = mode_flag
cmd = self.tika_start_command_list + [
'-J', '-t', f'-e{encoding_name}', local_path
]
def err(line):
logger.info(f'TIKA parsing {original_file_name}:\n{line}')
text = read_output(cmd,
stderr_callback=err,
encoding=encoding_name,
timeout_sec=timeout) or ''
try:
return _parse((200, text))
except Exception as ex:
text_sample = text[:255] if text and isinstance(text,
str) else str(text)
raise Exception(
'Error in parse_default_pdf_ocr -> _parse(). Text:\n' +
text_sample) from ex
def parse_file_local_xhtml(self,
local_path: str,
original_file_name: str,
timeout: int = 60,
encoding_name: str = 'utf-8',
logger: ProcessLogger = None,
enable_ocr: bool = True) -> MarkedUpText:
"""
Parses file (*.pdf, *.doc, *.docx, *.rtf, ...) calling Tika as a Java local process.
Tika will return XHTML and TikaXhtmlParser then will parse XHTML into plain text
plus extra formatting information plus metadata.
:param local_path: local path to the file being parsed
:param original_file_name: original file name, can differ from local_path (e.g. temporary file path)
:param timeout: timeout to interrupt Java process in seconds
:param encoding_name: encoding to use, is passed to Tika
:param logger: logger object to write errors and warnings
:param enable_ocr: allow (True) converting images to text
:return: MarkedUpText: text + metadata
"""
mode_flag = self.TIKA_MODE_OCR if enable_ocr else self.TIKA_MODE_PDF_ONLY
os.environ[self.TIKA_ENV_VAR_FLAG_MODE] = mode_flag
def err(line):
logger.info(f'TIKA parsing {original_file_name}:\n{line}')
for cmd_list in [
self.tika_default_command_list,
self.tika_lexnlp_default_command_list
]:
cmd = cmd_list + ['-x', f'-e{encoding_name}', local_path]
last_try = cmd == self.tika_lexnlp_default_command_list
text = read_output(cmd,
stderr_callback=err,
encoding=encoding_name,
timeout_sec=timeout) or ''
try:
output = self.xhtml_parser.parse_text(text)
output_len = len(output.text) if output and output.text else 0
logger.info(
f'parse_file_local_xhtml: {len(text)} source boiled down to {output_len}'
)
if not output_len and not last_try:
continue
output.meta[Document.DocumentMetadataKey.KEY_PARSING_STATISTICS] = \
{
'extracted_text_length': self.xhtml_parser.parse_stat.parsed_text_len,
'images_text_length': self.xhtml_parser.parse_stat.parsed_ocr_text_len,
}
return output
except Exception as ex:
text_sample = text[:255] if text and isinstance(
text, str) else str(text)
raise Exception(
'Error in parse_default_pdf_ocr -> _parse(). Text:\n' +
text_sample) from ex
def parse_file_local_plain_text(self,
local_path: str,
original_file_name: str,
task: Any,
timeout: int = 60,
encoding_name: str = 'utf-8',
logger: ProcessLogger = None,
enable_ocr: bool = True) -> MarkedUpText:
"""
Parses file (*.pdf, *.doc, *.docx, *.rtf, ...) calling Tika as a Java local process.
Tika will use plain text "stripper" and transform the source document into plain text
inside its (Java) process.
:param local_path: local path to the file being parsed
:param original_file_name: original file name, can differ from local_path (e.g. temporary file path)
:param timeout: timeout to interrupt Java process in seconds
:param encoding_name: encoding to use, is passed to Tika
:param logger: logger object to write errors and warnings
:param enable_ocr: allow (True) converting images to text
:return: MarkedUpText: text + metadata
"""
mode_flag = self.TIKA_MODE_OCR if enable_ocr else self.TIKA_MODE_PREFER_TEXT
# don't use at all TIKA_MODE_PDF_ONLY
os.environ[self.TIKA_ENV_VAR_FLAG_MODE] = mode_flag
os.environ[self.TIKA_PARSER_DETAIL] = ''
tika_default_command_list = self.tika_lexnlp_default_command_list
if enable_ocr is False and self.tika_noocr_default_command_list is not None:
tika_default_command_list = self.tika_noocr_default_command_list
cmd = tika_default_command_list + [
'-J', '-t', f'-e{encoding_name}', local_path
]
def err(line):
logger.info(f'TIKA parsing {original_file_name}:\n{line}')
logger.info(f'Tika (plain text) args: {", ".join(cmd)}')
text = read_output(cmd,
stderr_callback=err,
encoding=encoding_name,
timeout_sec=timeout,
task=task) or ''
try:
ptr_val = _parse((200, text))
return MarkedUpText(text=ptr_val['content'],
meta=ptr_val['metadata'])
except Exception as ex:
text_sample = text[:255] if text and isinstance(text,
str) else str(text)
raise Exception(
'Error in parse_default_pdf_ocr -> _parse(). Text:\n' +
text_sample) from ex
def pdf_has_images(file_path, task, logger=None, timeout=600):
"""
Check whether PDF file has images
:param file_path: str
:param task: celery task
:param logger: ProcessLogger
:param timeout: timeout sec
:return: bool
"""
def err(line):
logger.info(f'pdfimages parsing {file_path}:\n{line}')
cmd = ['pdfimages', '-list', file_path]
out = read_output(cmd, stderr_callback=err, timeout_sec=timeout,
task=task) or ''
return process_image_list(out)
def parse_file_local_xhtml(self,
local_path: str,
original_file_name: str,
task: Any,
timeout: int = 60,
encoding_name: str = 'utf-8',
logger: ProcessLogger = None,
enable_ocr: bool = True) -> MarkedUpText:
"""
Parses file (*.pdf, *.doc, *.docx, *.rtf, ...) calling Tika as a Java local process.
Tika will return XHTML and TikaXhtmlParser then will parse XHTML into plain text
plus extra formatting information plus metadata.
:param local_path: local path to the file being parsed
:param original_file_name: original file name, can differ from local_path (e.g. temporary file path)
:param timeout: timeout to interrupt Java process in seconds
:param encoding_name: encoding to use, is passed to Tika
:param logger: logger object to write errors and warnings
:param enable_ocr: allow (True) converting images to text
:return: MarkedUpText: text + metadata
"""
mode_flag = self.TIKA_MODE_OCR if enable_ocr else self.TIKA_MODE_PDF_ONLY
os.environ[self.TIKA_ENV_VAR_FLAG_MODE] = mode_flag
def err(line):
logger.info(f'TIKA parsing {original_file_name}:\n{line}')
tika_default_command_list = self.tika_lexnlp_default_command_list
if enable_ocr is False and self.tika_noocr_default_command_list is not None:
tika_default_command_list = self.tika_noocr_default_command_list
parse_commands = [
tika_default_command_list, self.tika_default_command_list
]
from apps.document.app_vars import TIKA_PROCESS_RAM_MB_LIMIT
ram_limit = TIKA_PROCESS_RAM_MB_LIMIT.val
for cmd_index in range(len(parse_commands)):
cmd_list = parse_commands[cmd_index]
cmd = cmd_list + ['-x', f'-e{encoding_name}', local_path]
if ram_limit:
java_index = cmd.index('java')
cmd = cmd[:java_index + 1] + [f'-Xmx{ram_limit}m'
] + cmd[java_index + 1:]
logger.info(f'Tika (XHTML) args: {", ".join(cmd)}')
last_try = cmd_index == len(parse_commands) - 1
text = read_output(cmd,
stderr_callback=err,
encoding=encoding_name,
timeout_sec=timeout,
task=task) or ''
try:
output = self.xhtml_parser.parse_text(text)
output_len = output.pure_text_length if output else 0
logger.info(
f'parse_file_local_xhtml: {len(text)} source boiled down to {output_len}'
)
if not output_len and not last_try:
continue
output.meta[Document.DocumentMetadataKey.KEY_PARSING_STATISTICS] = \
{
'extracted_text_length': self.xhtml_parser.parse_stat.parsed_text_len,
'images_text_length': self.xhtml_parser.parse_stat.parsed_ocr_text_len,
}
return output
except Exception as ex:
text_sample = text[:255] if text and isinstance(
text, str) else str(text)
raise Exception(
'Error in parse_default_pdf_ocr -> _parse(). Text:\n' +
text_sample) from ex
