make binary paths configurable

changelog.md

@@ -1,5 +1,14 @@
+
 # Changelog
 
+
+## [1.2.6] - 11 August 2020
+
+### Added
+
+- mglib.conf.settings module. The points it to get rid of hardcoded binary paths. Binary paths are now provided as configurations.
+
+
 ## [1.2.3] - 25 July 2020
 
 ### Changed

mglib/conf/__init__.py

@@ -0,0 +1,8 @@
+from .settings import (
+    DefaultSettings,
+    MgLibSettings
+)
+
+settings = MgLibSettings(
+    DefaultSettings()
+)

mglib/conf/default_settings.py

@@ -0,0 +1,28 @@
+
+
+# file utility used to find out mime type of a file
+BINARY_FILE = "/usr/bin/file"
+
+# Provided by ImageMagick package.
+# Used for resizing images.
+BINARY_CONVERT = "/usr/bin/convert"
+
+# Provided by Poppler Utils.
+# Used to extract images from PDF file.
+BINARY_PDFTOPPM = "/usr/bin/pdftoppm"
+
+# Provided by Poppler Utils.
+# used to get page count in PDF file
+BINARY_PDFINFO = "/usr/bin/pdfinfo"
+
+# Provided by ImageMagick package.
+# Used to get number of pages in TIFF file.
+BINARY_IDENTIFY = "/usr/bin/identify"
+
+# Provided by tesseract package.
+# Used to extract text from images/PDF files.
+BINARY_OCR = "/usr/bin/tesseract"
+
+# Provided by pdftk package
+# Used to reorder, cut/paste, delete pages withing PDF document
+BINARY_PDFTK = "/usr/bin/pdftk"

mglib/conf/settings.py

@@ -0,0 +1,55 @@
+import importlib
+
+try:
+    from django.conf import settings as django_settings
+except ImportError:
+    # Operating outside django, use own settings module
+    django_settings = None
+
+
+class DefaultSettings:
+
+    def __init__(
+        self,
+        settings_module="mglib.conf.default_settings"
+    ):
+        self.SETTINGS_MODULE = settings_module
+
+        mod = importlib.import_module(
+            self.SETTINGS_MODULE
+        )
+
+        for setting in dir(mod):
+            if setting.isupper():
+                setting_value = getattr(mod, setting)
+                setattr(self, setting, setting_value)
+
+    def configure(self, **options):
+        for name, value in options.items():
+            setattr(self, name, value)
+
+
+class MgLibSettings:
+
+    def __init__(
+        self, default_settings
+    ):
+        self.default_settings = default_settings
+
+    def __getattr__(self, name):
+        # When operating withing django,
+        # get configuration from django settings
+        if not name.isupper():
+            raise AttributeError
+
+        if django_settings:
+            val = getattr(django_settings, name)
+            return val
+
+        val = getattr(self.default_settings, name)
+        return val
+
+    def configure(self, **options):
+        self.default_settings.configure(
+            **options
+        )

mglib/mime.py

@@ -1,13 +1,14 @@
 import logging
 from . import wrapper
 
+from .conf import settings
 
 logger = logging.getLogger(__name__)
 
 
 class Mime(wrapper.Wrapper):
     def __init__(self, filepath):
-        super().__init__(exec_name="file")
+        super().__init__(exec_name=settings.BINARY_FILE)
         self.filepath = filepath
 
     def get_cmd(self):

mglib/pdfinfo.py

@@ -3,6 +3,8 @@
 import subprocess
 import logging
 
+from .conf import settings
+
 """
 Uses command line pdfinfo utility (from poppler pakage) for various
 small operations (e.g. get pdf page count).
@@ -13,7 +15,7 @@
 
 def get_tiff_pagecount(filepath):
     cmd = [
-        "/usr/bin/identify",
+        settings.BINARY_IDENTIFY,
         "-format",
         "%n\n",
         filepath
@@ -76,10 +78,11 @@ def get_pagecount(filepath):
             "Only jpeg, png, pdf and tiff are handlerd by this"
             " method"
         )
-
     # pdfinfo "${PDFFILE}" | grep Pages
-
-    cmd = ["/usr/bin/pdfinfo", filepath]
+    cmd = [
+        settings.BINARY_PDFINFO,
+        filepath
+    ]
     compl = subprocess.run(
         cmd,
         stdout=subprocess.PIPE,

mglib/pdftk.py

@@ -3,6 +3,8 @@
 from mglib.runcmd import run
 from mglib.pdfinfo import get_pagecount
 
+from .conf import settings
+
 logger = logging.getLogger(__name__)
 
 #
@@ -183,7 +185,7 @@ def paste_pages_into_existing_doc(
         )
 
     cmd = [
-        "pdftk",
+        settings.BINARY_PDFTK,
     ]
     # add A=doc1_path, B=doc2_path
     cmd.extend(letters_2_doc_map)
@@ -272,7 +274,7 @@ def paste_pages(
             )
 
     cmd = [
-        "pdftk",
+        settings.BINARY_PDFTK,
     ]
     # add A=doc1_path, B=doc2_path
     cmd.extend(letters_2_doc_map)
@@ -315,7 +317,7 @@ def reorder_pages(
     )
 
     cmd = [
-        "pdftk",
+        settings.BINARY_PDFTK,
         src,
         "cat"
     ]
@@ -338,7 +340,7 @@ def delete_pages(src, dst, page_numbers):
     )
 
     cmd = [
-        "pdftk",
+        settings.BINARY_PDFTK,
         src,
         "cat"
     ]

mglib/shortcuts.py

@@ -2,6 +2,7 @@
 import logging
 
 from mglib.runcmd import run
+from .conf import settings
 
 logger = logging.getLogger(__name__)
 
@@ -28,7 +29,7 @@ def resize_img(page_path, media_root):
         logger.debug(f"PPMROOT {ppmroot_dirname} already exists.")
 
     cmd = (
-        "convert",
+        settings.BINARY_CONVERT,
         "-resize",
         f"{width}x",
         local_abspath,
@@ -61,7 +62,7 @@ def extract_img(page_path, media_root):
     else:
         logger.debug(f"PPMROOT {ppmroot_dirname} already exists.")
     cmd = (
-        "pdftoppm",
+        settings.BINARY_PDFTOPPM,
         "-jpeg",
         "-f",
         str(page_num),
@@ -89,7 +90,7 @@ def extract_hocr(page_url, lang, media_root):
         os.path.join(media_root, page_url.hocr_url())
     )
     cmd = (
-        "tesseract",
+        settings.BINARY_OCR,
         "-l",
         lang,
         page_abspath,
@@ -112,37 +113,10 @@ def extract_txt(page_url, lang, media_root):
         )
     )
     cmd = (
-        "tesseract",
+        settings.BINARY_OCR,
         "-l",
         lang,
         page_abspath,
         txt_root
     )
     run(cmd)
-
-
-#def text_from_pdf(filepath, lang, dry_run=False):
-#
-#    # suffix .tiff in file name is required by conver utility, otherwise
-#    # it won't convert to tiff format!
-#    tiff = tempfile.NamedTemporaryFile(suffix=".tiff")
-#    conv = convert.Convert(dry_run=dry_run)
-#    conv(filepath=filepath, fout=tiff)
-#    try:
-#        tsact = tesseract.Tesseract()
-#        text = tsact(filepath=tiff.name, lang=lang)
-#    except subprocess.CalledProcessError as e:
-#        print(e)
-#        print(e.stderr)
-#        return
-#
-#    return text
-#
-#
-#def text_from_image(filepath, lang, dry_run=False):
-#
-#    tsact = tesseract.Tesseract(dry_run=dry_run)
-#    text = tsact(filepath=filepath, lang=lang)
-#
-#    return text
-#

mglib/tiff.py

@@ -2,6 +2,7 @@
 import logging
 
 from mglib.runcmd import run
+from .conf import settings
 
 logger = logging.getLogger(__name__)
 
@@ -21,7 +22,7 @@ def convert_tiff2pdf(doc_url):
     )
 
     cmd = (
-        "convert",
+        settings.BINARY_CONVERT,
         doc_url,
         new_doc_url,
     )

setup.py

@@ -6,7 +6,7 @@
 
 setup(
     name="mglib",
-    version="1.2.5",
+    version="1.2.6",
     author="Eugen Ciur",
     author_email="eugen@papermerge.com",
     url="https://github.com/papermerge/mglib",

test/test_settings.py

@@ -0,0 +1,45 @@
+import os
+from pathlib import Path
+import unittest
+
+from mglib.conf.settings import (
+    MgLibSettings,
+    DefaultSettings
+)
+
+DATA_DIR = os.path.join(
+    Path(__file__).parent,
+    'data'
+)
+
+
+class TestMgLibSettings(unittest.TestCase):
+
+    def setUp(self):
+        self.settings = MgLibSettings(DefaultSettings())
+
+    def test_settings_outside_django_should_work(self):
+        """
+        Without django there should be default values
+        for settings
+        """
+        # check default value for pdfinfo
+        self.assertEqual(
+            "/usr/bin/pdfinfo",
+            self.settings.BINARY_PDFINFO
+        )
+
+    def test_settings_are_configurable(self):
+        """
+        User should be able to reconfigure mglibsettings
+        on the go (i.e. change default values).
+        """
+        # check default value for pdfinfo
+        self.settings.configure(
+            BINARY_PDFINFO="/usr/bin/xyz"
+        )
+        self.assertEqual(
+            "/usr/bin/xyz",
+            self.settings.BINARY_PDFINFO
+        )
+