v8.2.3 notes

The LeptonicaErrorTrap was problematic for Celery and other
libraries that mess with stderr.

Closes #359

README.md

@@ -38,9 +38,9 @@ Main features
 - If requested deskews and/or cleans the image before performing OCR
 - Validates input and output files
 - Distributes work across all available CPU cores
-- Uses [Tesseract OCR](https://github.com/tesseract-ocr/tesseract) engine
-- Supports more than [100 languages](https://github.com/tesseract-ocr/tessdata) recognized by Tesseract
-- Battle-tested on thousands of PDFs, a test suite and continuous integration
+- Uses [Tesseract OCR](https://github.com/tesseract-ocr/tesseract) engine to recognize more than [100 languages](https://github.com/tesseract-ocr/tessdata)
+- Scales properly to handle files with thousands of pages
+- Battle-tested on millions of PDFs
 
 For details: please consult the [documentation](https://ocrmypdf.readthedocs.io/en/latest/).
 
@@ -131,6 +131,11 @@ Press & Media
 - [c't 1-2014, page 59](http://heise.de/-2279695): Detailed presentation of OCRmyPDF v1.0 in the leading German IT magazine c't
 - [heise Open Source, 09/2014: Texterkennung mit OCRmyPDF](http://heise.de/-2356670)
 
+Business enquiries
+------------------
+
+OCRmyPDF would not be the software that it is today is without companies and users choosing to provide support for feature development and consulting enquiries. We are happy to discuss all enquiries, whether for extending the existing feature set, or integrating OCRmyPDF into a larger system.
+
 License
 -------
 
@@ -138,7 +143,7 @@ The OCRmyPDF software is licensed under the GNU GPLv3. Certain files are covered
 
 The license for each test file varies, and is noted in tests/resources/README.rst. The documentation is licensed under Creative Commons Attribution-ShareAlike 4.0 (CC-BY-SA 4.0).
 
-OCRmyPDF versions prior to 6.0 were licensed under the MIT License.
+OCRmyPDF versions prior to 6.0 were distributed under the MIT License.
 
 Disclaimer
 ----------

docs/batch.rst

@@ -27,7 +27,13 @@ This will walk through a directory tree and run OCR on all files in place, print
 
 .. code-block:: bash
 
-	find . --printf '%p' -name '*.pdf' -exec ocrmypdf '{}' '{}' \;
+	find . -printf '%p' -name '*.pdf' -exec ocrmypdf '{}' '{}' \;
+	
+Alternatively, with a docker container (mounts a volume to the container where the PDFs are stored):
+
+.. code-block:: bash
+
+	find . -printf '%p' -name '*.pdf' -exec docker run --rm -v <host dir>:<container dir> jbarlow83/ocrmypdf-alpine '<container dir>/{}' '<container dir>/{}' \;
 
 This only runs one ``ocrmypdf`` process at a time. This variation uses ``find`` to create a directory list and ``parallel`` to parallelize runs of ``ocrmypdf``, again updating files in place.
 
@@ -163,14 +169,11 @@ This is only possible for x86-based Synology products. Some Synology products us
 	            shutil.move(full_path, full_path_archive)
 	logging.info('Finished.\n')
 
-
-
 Huge batch jobs
 """""""""""""""
 
 If you have thousands of files to work with, contact the author. Consulting work related to OCRmyPDF helps fund this open source project and all inquiries are appreciated.
 
-
 Hot (watched) folders
 ---------------------
 
@@ -210,3 +213,13 @@ Alternatives
 """"""""""""
 
 * `Watchman <https://facebook.github.io/watchman/>`_ is a more powerful alternative to ``watchmedo``.
+
+macOS Automator
+---------------
+
+You can use the Automator app with macOS, to create a Workflow or Quick Action. Use a *Run Shell Script* action in your workflow. In the context of Automator, the ``PATH`` may be set differently your Terminal's ``PATH``; you may need to explicitly set the PATH to include ``ocrmypdf``. The following example may serve as a starting point:
+
+.. image:: images/macos-workflow.png
+	:alt: Example macOS Automator script
+
+You may customize the command sent to ocrmypdf.

docs/docker.rst

@@ -104,7 +104,7 @@ Clients must keep their open connection while waiting for OCR to complete. This
 
 Unlike the rest of OCRmyPDF, this web service is licensed under the Affero GPLv3 (AGPLv3) since Ghostscript, a dependency of OCRmyPDF, is also licensed in this way.
 
-In addition to the above, please read our :ref:`general remarks on using OCRmyPDF as a service <ocr-service>`_.
+In addition to the above, please read our :ref:`general remarks on using OCRmyPDF as a service <ocr-service>`.
 
 Legacy Ubuntu Docker images
 ---------------------------

docs/introduction.rst

@@ -16,7 +16,7 @@ About PDFs
 
 PDFs are page description files that attempts to preserve a layout exactly. They  contain `vector graphics <http://vector-conversions.com/vectorizing/raster_vs_vector.html>`_ that can contain raster objects such as scanned images. Because PDFs can contain multiple pages (unlike many image formats) and can contain fonts and text, it is a good formats for exchanging scanned documents.
 
-.. image:: bitmap_vs_svg.svg
+.. image:: images/bitmap_vs_svg.svg
 
 A PDF page might contain multiple images, even if it only appears to have one image.  Some scanners or scanning software will segment pages into monochromatic text and color regions for example, to improve the compression ratio and appearance of the page.
 

docs/release_notes.rst

@@ -13,6 +13,15 @@ Note that it is licensed under GPLv3, so scripts that ``import ocrmypdf`` and ar
    find:    [^`]\#([0-9]{1,3})[^0-9]
    replace: `#$1 <https://github.com/jbarlow83/OCRmyPDF/issues/$1>`_
 
+v8.2.3
+------
+
+-   Fixed that ``--mask-barcodes`` would occasionally leave a unwanted temporary file named ``junkpixt`` in the current working folder.
+
+-   Fixed (hopefully) handling of Leptonica errors in an environment where a non-standard ``sys.stderr`` is present.
+
+-   Improved help text for ``--verbose``.
+
 v8.2.2
 ------
 

src/ocrmypdf/__main__.py

@@ -231,7 +231,9 @@ jobcontrol.add_argument(
     default=[],
     nargs='?',
     action="append",
-    help="Print more verbose messages for each additional verbose level",
+    help="Print more verbose messages for each additional verbose level. Use "
+    "`-v 1` typically for much more detailed logging. Higher numbers "
+    "are probably only useful in debugging.",
 )
 
 metadata = parser.add_argument_group(

src/ocrmypdf/leptonica.py

@@ -43,11 +43,6 @@ lept = ffi.dlopen(find_library('lept'))
 lept.setMsgSeverity(lept.L_SEVERITY_WARNING)
 
 
-def stderr(*objs):
-    """Shorthand print to stderr."""
-    print("leptonica.py:", *objs, file=sys.stderr)
-
-
 class _LeptonicaErrorTrap:
     """
     Context manager to trap errors reported by Leptonica.
@@ -66,6 +61,7 @@ class _LeptonicaErrorTrap:
     def __init__(self):
         self.tmpfile = None
         self.copy_of_stderr = -1
+        self.no_stderr = False
 
     def __enter__(self):
         from io import UnsupportedOperation
@@ -73,33 +69,40 @@ class _LeptonicaErrorTrap:
         self.tmpfile = TemporaryFile()
 
         # Save the old stderr, and redirect stderr to temporary file
-        sys.stderr.flush()
+        with suppress(AttributeError):
+            sys.stderr.flush()
         try:
             self.copy_of_stderr = os.dup(sys.stderr.fileno())
             os.dup2(self.tmpfile.fileno(), sys.stderr.fileno(), inheritable=False)
+        except AttributeError:
+            # We are in some unusual context where our Python process does not
+            # have a sys.stderr. Leptonica still expects to write to file
+            # descriptor 2, so we are going to ensure it is redirected.
+            self.copy_of_stderr = None
+            self.no_stderr = True
+            os.dup2(self.tmpfile.fileno(), 2, inheritable=False)
         except UnsupportedOperation:
             self.copy_of_stderr = None
         return
 
     def __exit__(self, exc_type, exc_value, traceback):
         # Restore old stderr
-        sys.stderr.flush()
+        with suppress(AttributeError):
+            sys.stderr.flush()
+
         if self.copy_of_stderr is not None:
             os.dup2(self.copy_of_stderr, sys.stderr.fileno())
             os.close(self.copy_of_stderr)
+        if self.no_stderr:
+            os.close(2)
 
-        # Get data from tmpfile (in with block to ensure it is closed)
-        with self.tmpfile as tmpfile:
-            tmpfile.seek(0)  # Cursor will be at end, so move back to beginning
-            leptonica_output = tmpfile.read().decode(errors='replace')
-
-        assert self.tmpfile.closed
-        assert not sys.stderr.closed
-
-        # If there are Python errors, let them bubble up
+        # Get data from tmpfile
+        self.tmpfile.seek(0)  # Cursor will be at end, so move back to beginning
+        leptonica_output = self.tmpfile.read().decode(errors='replace')
+        self.tmpfile.close()
+        # If there are Python errors, record them
         if exc_type:
             logger.warning(leptonica_output)
-            return False
 
         # If there are Leptonica errors, wrap them in Python excpetions
         if 'Error' in leptonica_output:
@@ -614,9 +617,10 @@ class Pix(LeptonicaObject):
         except (LeptonicaError, ValueError, IndexError):
             return
         finally:
-            with suppress(FileNotFoundError):
-                os.unlink('junkpixt.png')  # leptonica may produce this
-                os.unlink('junkpixt')
+            leptonica_junk = ('junkpixt.png', 'junkpixt')
+            for junk in leptonica_junk:
+                with suppress(FileNotFoundError):
+                    os.unlink(junk)  # leptonica may produce this
 
         for n, s in enumerate(sarray):
             decoded = s.decode()

tests/test_lept.py

@@ -17,7 +17,9 @@
 
 
 from os import fspath
+import os
 from pickle import dumps, loads
+from unittest.mock import patch
 
 import pytest
 from PIL import Image, ImageChops
@@ -85,3 +87,18 @@ def test_leptonica_compile(tmpdir):
     # existing compiled library. Also compile in API mode so that we test
     # the interfaces, even though we use it ABI mode.
     ffibuilder.compile(tmpdir=fspath(tmpdir), target=fspath(tmpdir / 'lepttest.*'))
+
+
+def test_with_stderr(capsys):
+    # pytest redirects stderr too; we must disable this for the test to be valid
+    with capsys.disabled():
+        with pytest.raises(FileNotFoundError):
+            lept.Pix.open("does_not_exist1")
+
+
+def test_without_stderr(capsys):
+    # pytest redirects stderr too; we must disable this for the test to be valid
+    with capsys.disabled():
+        with patch('sys.stderr', new=None):
+            with pytest.raises(FileNotFoundError):
+                lept.Pix.open("does_not_exist2")