Avoid missing hashlib.file_digest for Python < 3.11.

sdks/python/apache_beam/yaml/yaml_provider.py

@@ -1057,7 +1057,7 @@ def normalize_package(package):
         # Ignore the exact path by which this package was referenced,
         # but do create a new environment if it changed.
         with open(package, 'rb') as fin:
-          return os.path.basename(package) + '-' + hashlib.file_digest(
+          return os.path.basename(package) + '-' + _file_digest(
               fin, 'sha256').hexdigest()
       else:
         # Assume urls and pypi identifiers are immutable.
@@ -1363,3 +1363,15 @@ def standard_providers():
       io_providers(),
       load_providers(
           os.path.join(os.path.dirname(__file__), 'standard_providers.yaml')))
+
+
+def _file_digest(fileobj, digest):
+  if hasattr(hashlib, 'file_digest'):  # Python 3.11+
+    return hashlib.file_digest(fileobj, digest)
+  else:
+    hasher = hashlib.new(digest)
+    data = fileobj.read(1 << 20)
+    while data:
+      hasher.update(data)
+      data = fileobj.read(1 << 20)
+    return hasher

sdks/python/apache_beam/yaml/yaml_provider_unit_test.py

@@ -261,6 +261,48 @@ def test_recursive(self):
       assert_that(result | beam.Map(lambda x: x.value), equal_to([120]))
 
 
+class PythonProviderDepsTest(unittest.TestCase):
+  def test_env_package_sensitive(self):
+    self.assertNotEqual(
+        yaml_provider.PypiExpansionService._key('base', ['pkg1']),
+        yaml_provider.PypiExpansionService._key('base', ['pkg2']))
+
+  def test_env_base_sensitive(self):
+    self.assertNotEqual(
+        yaml_provider.PypiExpansionService._key('base1', ['pkg']),
+        yaml_provider.PypiExpansionService._key('base2', ['pkg']))
+
+  def test_env_order_invariant(self):
+    self.assertEqual(
+        yaml_provider.PypiExpansionService._key('base', ['pkg1', 'pkg2']),
+        yaml_provider.PypiExpansionService._key('base', ['pkg2', 'pkg1']))
+
+  def test_env_path_invariant(self):
+    with tempfile.TemporaryDirectory() as tmpdir:
+      os.mkdir(os.path.join(tmpdir, 'a'))
+      pkgA = os.path.join(tmpdir, 'a', 'pkg.tgz')
+      os.mkdir(os.path.join(tmpdir, 'b'))
+      pkgB = os.path.join(tmpdir, 'b', 'pkg.tgz')
+      with open(pkgA, 'w') as fout:
+        fout.write('content')
+      with open(pkgB, 'w') as fout:
+        fout.write('content')
+      self.assertEqual(
+          yaml_provider.PypiExpansionService._key('base', [pkgA]),
+          yaml_provider.PypiExpansionService._key('base', [pkgB]))
+
+  def test_env_content_sensitive(self):
+    with tempfile.TemporaryDirectory() as tmpdir:
+      pkg = os.path.join(tmpdir, 'pkg.tgz')
+      with open(pkg, 'w') as fout:
+        fout.write('content')
+      before = yaml_provider.PypiExpansionService._key('base', [pkg])
+      with open(pkg, 'w') as fout:
+        fout.write('new content')
+      after = yaml_provider.PypiExpansionService._key('base', [pkg])
+      self.assertNotEqual(before, after)
+
+
 if __name__ == '__main__':
   logging.getLogger().setLevel(logging.INFO)
   unittest.main()