Github user jkbradley commented on a diff in the pull request:
https://github.com/apache/spark/pull/18742#discussion_r131331793
--- Diff: python/pyspark/ml/util.py ---
@@ -61,32 +66,89 @@ def _randomUID(cls):
@inherit_doc
-class MLWriter(object):
+class BaseReadWrite(object):
+ """
+ Base class for MLWriter and MLReader. Stores information about the
SparkContext
+ and SparkSession.
+
+ .. versionadded:: 2.3.0
+ """
+
+ def __init__(self):
+ self._sparkSession = None
+
+ def context(self, sqlContext):
+ """
+ Sets the Spark SQLContext to use for saving/loading.
+
+ .. note:: Deprecated in 2.1 and will be removed in 3.0, use
session instead.
+ """
+ raise NotImplementedError("Read/Write is not yet implemented for
type: %s" % type(self))
+
+ def session(self, sparkSession):
+ """
+ Sets the Spark Session to use for saving/loading.
+ """
+ self._sparkSession = sparkSession
+ return self
+
+ @property
+ def sparkSession(self):
+ """
+ Returns the user-specified Spark Session or the default.
+ """
+ if self._sparkSession is None:
+ self._sparkSession = SparkSession.builder.getOrCreate()
+ return self._sparkSession
+
+ @property
+ def sc(self):
+ """
+ Returns the underlying `SparkContext`.
+ """
+ return self.sparkSession.sparkContext
+
+
+@inherit_doc
+class MLWriter(BaseReadWrite):
"""
Utility class that can save ML instances.
.. versionadded:: 2.0.0
"""
+ def __init__(self):
+ super(MLWriter, self).__init__()
+ self.shouldOverwrite = False
+
+ def _handleOverwrite(self, path):
+ from pyspark.ml.wrapper import JavaWrapper
+
+ _java_obj =
JavaWrapper._new_java_obj("org.apache.spark.ml.util.FileSystemOverwrite")
+ wrapper = JavaWrapper(_java_obj)
+ wrapper._call_java("handleOverwrite", path, True,
self.sc._jsc.sc())
+
def save(self, path):
"""Save the ML instance to the input path."""
- raise NotImplementedError("MLWriter is not yet implemented for
type: %s" % type(self))
-
- def overwrite(self):
- """Overwrites if the output path already exists."""
- raise NotImplementedError("MLWriter is not yet implemented for
type: %s" % type(self))
+ if self.shouldOverwrite:
+ self._handleOverwrite(path)
+ self.saveImpl(path)
- def context(self, sqlContext):
+ def saveImpl(self, path):
"""
- Sets the SQL context to use for saving.
-
- .. note:: Deprecated in 2.1 and will be removed in 3.0, use
session instead.
+ save() handles overwriting and then calls this method. Subclasses
should override this
+ method to implement the actual saving of the instance.
"""
raise NotImplementedError("MLWriter is not yet implemented for
type: %s" % type(self))
+ def overwrite(self):
+ """Overwrites if the output path already exists."""
+ self.shouldOverwrite = True
+ return self
+
def session(self, sparkSession):
--- End diff --
You can remove this instance of session since it is inherited.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
