Repository: great-expectations/great_expectations

Issue:
Use cleaner solution for non-truncating division in python 2
Prefer `from __future__ import division` to `1.*x/y`


Discussion:
Done inline during improve_partitions push.

Resolving patch:
diff --git a/contrib/experimental/great_expectations_experimental/expectations/expect_column_values_url_has_got_valid_cert.py b/contrib/experimental/great_expectations_experimental/expectations/expect_column_values_url_has_got_valid_cert.py
new file mode 100644
--- /dev/null
+++ b/contrib/experimental/great_expectations_experimental/expectations/expect_column_values_url_has_got_valid_cert.py
@@ -0,0 +1,183 @@
+"""
+This is a template for creating custom ColumnMapExpectations.
+For detailed instructions on how to use it, please see:
+    https://docs.greatexpectations.io/docs/guides/expectations/creating_custom_expectations/how_to_create_custom_column_map_expectations
+"""
+import datetime
+import json
+import socket
+import ssl
+from datetime import datetime
+from typing import Optional
+
+from dateutil.parser import parse
+
+from great_expectations.core.expectation_configuration import ExpectationConfiguration
+from great_expectations.exceptions import InvalidExpectationConfigurationError
+from great_expectations.execution_engine import PandasExecutionEngine
+from great_expectations.expectations.expectation import ColumnMapExpectation
+from great_expectations.expectations.metrics import (
+    ColumnMapMetricProvider,
+    column_condition_partial,
+)
+
+
+def get_certificate_exp_date(host, port=443, timeout=1):
+    try:
+        context = ssl.create_default_context()
+        conn = socket.create_connection((host, port))
+        sock = context.wrap_socket(conn, server_hostname=host)
+        sock.settimeout(timeout)
+        cert = sock.getpeercert()
+        expiry_date = datetime.strptime(cert["notAfter"], "%b %d %H:%M:%S %Y %Z")
+        before_date = datetime.strptime(cert["notBefore"], "%b %d %H:%M:%S %Y %Z")
+        return before_date, expiry_date
+    except Exception as e:
+        return parse("1900-01-01"), parse("1900-01-01")
+    finally:
+        sock.close()
+
+
+def has_valid_cert(url: str) -> bool:
+    try:
+        before_date, expiry_date = get_certificate_exp_date(url)
+        if (
+            expiry_date > datetime.utcnow()
+            and before_date < datetime.utcnow()
+            and expiry_date is not None
+            and before_date is not None
+        ):
+            return True
+        else:
+            return False
+    except Exception as e:
+        return False
+
+
+# This class defines a Metric to support your Expectation.
+# For most ColumnMapExpectations, the main business logic for calculation will live in this class.
+class ColumnValuesUrlHasGotValidCert(ColumnMapMetricProvider):
+
+    # This is the id string that will be used to reference your metric.
+    condition_metric_name = "column_values.valid_cert"
+
+    # This method implements the core logic for the PandasExecutionEngine
+    @column_condition_partial(engine=PandasExecutionEngine)
+    def _pandas(cls, column, **kwargs):
+        return column.apply(lambda x: has_valid_cert(x))
+
+    # This method defines the business logic for evaluating your metric when using a SqlAlchemyExecutionEngine
+    # @column_condition_partial(engine=SqlAlchemyExecutionEngine)
+    # def _sqlalchemy(cls, column, _dialect, **kwargs):
+    #     raise NotImplementedError
+
+    # This method defines the business logic for evaluating your metric when using a SparkDFExecutionEngine
+    # @column_condition_partial(engine=SparkDFExecutionEngine)
+    # def _spark(cls, column, **kwargs):
+    #     raise NotImplementedError
+
+
+# This class defines the Expectation itself
+class ExpectColumnValuesUrlHasGotValidCert(ColumnMapExpectation):
+    """Expect provided url has got valid cert. (NotBefore < now < NotAfter"""
+
+    # These examples will be shown in the public gallery.
+    # They will also be executed as unit tests for your Expectation.
+    examples = [
+        {
+            "data": {
+                "all_valid": [
+                    "google.com",
+                    "index.hu",
+                    "yahoo.com",
+                    "github.com",
+                    "microsoft.com",
+                ],
+                "some_other": [
+                    "google.com",
+                    "index.hu",
+                    "yahoo.com",
+                    "github.com",
+                    "expired.badssl.com",
+                ],
+            },
+            "tests": [
+                {
+                    "title": "basic_positive_test",
+                    "exact_match_out": False,
+                    "include_in_gallery": True,
+                    "in": {"column": "all_valid"},
+                    "out": {
+                        "success": True,
+                    },
+                },
+                {
+                    "title": "basic_negative_test",
+                    "exact_match_out": False,
+                    "include_in_gallery": True,
+                    "in": {"column": "some_other", "mostly": 0.9},
+                    "out": {
+                        "success": False,
+                    },
+                },
+            ],
+        }
+    ]
+
+    # This is the id string of the Metric used by this Expectation.
+    # For most Expectations, it will be the same as the `condition_metric_name` defined in your Metric class above.
+    map_metric = "column_values.valid_cert"
+
+    # This is a list of parameter names that can affect whether the Expectation evaluates to True or False
+    success_keys = ("mostly",)
+
+    # This dictionary contains default values for any parameters that should have default values
+    default_kwarg_values = {}
+
+    def validate_configuration(
+        self, configuration: Optional[ExpectationConfiguration]
+    ) -> None:
+        """
+        Validates that a configuration has been set, and sets a configuration if it has yet to be set. Ensures that
+        necessary configuration arguments have been provided for the validation of the expectation.
+
+        Args:
+            configuration (OPTIONAL[ExpectationConfiguration]): \
+                An optional Expectation Configuration entry that will be used to configure the expectation
+        Returns:
+            None. Raises InvalidExpectationConfigurationError if the config is not validated successfully
+        """
+
+        super().validate_configuration(configuration)
+        if configuration is None:
+            configuration = self.configuration
+
+        # # Check other things in configuration.kwargs and raise Exceptions if needed
+        # try:
+        #     assert (
+        #         ...
+        #     ), "message"
+        #     assert (
+        #         ...
+        #     ), "message"
+        # except AssertionError as e:
+        #     raise InvalidExpectationConfigurationError(str(e))
+
+        return True
+
+    # This object contains metadata for display in the public Gallery
+    library_metadata = {
+        "maturity": "experimental",
+        "tags": [
+            "hackathon-22",
+            "experimental",
+            "typed-entities",
+        ],  # Tags for this Expectation in the Gallery
+        "contributors": [  # Github handles for all contributors to this Expectation.
+            "@szecsip",  # Don't forget to add your github handle here!
+        ],
+    }
+
+
+if __name__ == "__main__":
+    ExpectColumnValuesUrlHasGotValidCert().print_diagnostic_checklist()


Test patch: