[SPARK-19570][PYSPARK] Allow to disable hive in pyspark shell

## What changes were proposed in this pull request?

SPARK-15236 do this for scala shell, this ticket is for pyspark shell. This is not only for pyspark itself, but can also benefit downstream project like livy which use shell.py for its interactive session. For now, livy has no control of whether enable hive or not.

## How was this patch tested?

I didn't find a way to add test for it. Just manually test it.
Run `bin/pyspark --master local --conf spark.sql.catalogImplementation=in-memory` and verify hive is not enabled.

Author: Jeff Zhang <zjffdu@apache.org>

Closes #16906 from zjffdu/SPARK-19570.

python/pyspark/shell.py

@@ -24,13 +24,13 @@ This file is designed to be launched as a PYTHONSTARTUP script.
 import atexit
 import os
 import platform
+import warnings
 
 import py4j
 
-import pyspark
+from pyspark import SparkConf
 from pyspark.context import SparkContext
 from pyspark.sql import SparkSession, SQLContext
-from pyspark.storagelevel import StorageLevel
 
 if os.environ.get("SPARK_EXECUTOR_URI"):
     SparkContext.setSystemProperty("spark.executor.uri", os.environ["SPARK_EXECUTOR_URI"])
@@ -39,13 +39,23 @@ SparkContext._ensure_initialized()
 
 try:
     # Try to access HiveConf, it will raise exception if Hive is not added
-    SparkContext._jvm.org.apache.hadoop.hive.conf.HiveConf()
-    spark = SparkSession.builder\
-        .enableHiveSupport()\
-        .getOrCreate()
+    conf = SparkConf()
+    if conf.get('spark.sql.catalogImplementation', 'hive').lower() == 'hive':
+        SparkContext._jvm.org.apache.hadoop.hive.conf.HiveConf()
+        spark = SparkSession.builder\
+            .enableHiveSupport()\
+            .getOrCreate()
+    else:
+        spark = SparkSession.builder.getOrCreate()
 except py4j.protocol.Py4JError:
+    if conf.get('spark.sql.catalogImplementation', '').lower() == 'hive':
+        warnings.warn("Fall back to non-hive support because failing to access HiveConf, "
+                      "please make sure you build spark with hive")
     spark = SparkSession.builder.getOrCreate()
 except TypeError:
+    if conf.get('spark.sql.catalogImplementation', '').lower() == 'hive':
+        warnings.warn("Fall back to non-hive support because failing to access HiveConf, "
+                      "please make sure you build spark with hive")
     spark = SparkSession.builder.getOrCreate()
 
 sc = spark.sparkContext