add BarCodeReader.zxing_version and BarCodeReader.zxing_version_info, and call it v0.13

Also, remove obsolete Python versions from .travis.yml, and migrate to openjdk-8-jre.

Author: dlenski

README.md

@@ -21,6 +21,8 @@ The `BarCodeReader` class is used to decode images:
 ```python
 >>> import zxing
 >>> reader = zxing.BarCodeReader()
+>>> print(reader.zxing_version, reader.zxing_version_info)
+3.4.1 (3, 4, 1)
 >>> barcode = reader.decode("test/barcodes/QR_CODE-easy.png")
 >>> print(barcode)
 BarCode(raw='This should be QR_CODE', parsed='This should be QR_CODE', format='QR_CODE', type='TEXT', points=[(15.0, 87.0), (15.0, 15.0), (87.0, 15.0), (75.0, 75.0)])

test/test_all.py

@@ -26,6 +26,14 @@ def setup_reader():
     if test_reader is None:
         test_reader = zxing.BarCodeReader()
 
+
+@with_setup(setup_reader)
+def test_version():
+    global test_reader
+    assert test_reader.zxing_version is not None
+    assert '.'.join(map(str, test_reader.zxing_version_info)) == test_reader.zxing_version
+
+
 @with_setup(setup_reader)
 def _check_decoding(filename, expected_format, expected_raw, extra={}):
     global test_reader

zxing/__init__.py

@@ -10,6 +10,7 @@
 from urllib.parse import quote
 from enum import Enum
 import pathlib
+import zipfile
 
 from .version import __version__
 import subprocess as sp, re, os
@@ -24,13 +25,21 @@ class BarCodeReader(object):
 
     def __init__(self, classpath=None, java=None):
         self.java = java or 'java'
+        self.zxing_version = self.zxing_version_info = None
         if classpath:
             self.classpath = classpath if isinstance(classpath, str) else ':'.join(classpath)
         elif "ZXING_CLASSPATH" in os.environ:
             self.classpath = os.environ.get("ZXING_CLASSPATH","")
         else:
             self.classpath = os.path.join(os.path.dirname(__file__), 'java', '*')
 
+        with zipfile.ZipFile(os.path.join(os.path.dirname(__file__), 'java', 'core.jar')) as c:
+            for line in c.open('META-INF/MANIFEST.MF'):
+                if line.startswith(b'Bundle-Version: '):
+                    self.zxing_version = line.split(b' ', 1)[1].strip().decode()
+                    self.zxing_version_info = tuple(int(n) for n in self.zxing_version.split('.'))
+                    break
+
     def decode(self, filenames, try_harder=False, possible_formats=None, pure_barcode=False, products_only=False):
         possible_formats = (possible_formats,) if isinstance(possible_formats, str) else possible_formats
 

zxing/version.py

@@ -1 +1 @@
-__version__="0.12"
+__version__="0.14"