feat: use importlib instead of deprecated pkg_resources for version

* Add very simple test for version argument
* Add python 3.7 compatibility for package metadata version

test/test_cli.py

@@ -12,6 +12,12 @@
 import tempfile
 import os
 
+def test_version(capsys):
+    with pytest.raises(SystemExit):
+        main(args=['--version'])
+    out, err = capsys.readouterr()
+    print(out, err)
+    assert len(out) > 0
 
 def test_index(capsys):
     files = ['example.warc.gz', 'example.warc', 'example.arc.gz', 'example.arc']

warcio/cli.py

@@ -5,6 +5,13 @@
 from warcio.extractor import Extractor
 from warcio.recompressor import Recompressor
 
+
+try:
+    from importlib.metadata import version
+except ImportError:
+    import pkg_resources
+    def version(package):
+        return pkg_resources.get_distribution(package).version
 import sys
 
 
@@ -57,8 +64,7 @@ def main(args=None):
 
 # ============================================================================
 def get_version():
-    import pkg_resources
-    return '%(prog)s ' + pkg_resources.get_distribution('warcio').version
+    return '%(prog)s ' + version('warcio')
 
 
 # ============================================================================