diff options
author | Davies Liu <davies@databricks.com> | 2015-02-09 20:49:22 -0800 |
---|---|---|
committer | Reynold Xin <rxin@databricks.com> | 2015-02-09 20:49:22 -0800 |
commit | 08488c175f2e8532cb6aab84da2abd9ad57179cc (patch) | |
tree | 05b7076b329fd8710ab650f91c38af3bf1a6a2d9 /python/pyspark/sql/context.py | |
parent | d302c4800bf2f74eceb731169ddf1766136b7398 (diff) | |
download | spark-08488c175f2e8532cb6aab84da2abd9ad57179cc.tar.gz spark-08488c175f2e8532cb6aab84da2abd9ad57179cc.tar.bz2 spark-08488c175f2e8532cb6aab84da2abd9ad57179cc.zip |
[SPARK-5469] restructure pyspark.sql into multiple files
All the DataTypes moved into pyspark.sql.types
The changes can be tracked by `--find-copies-harder -M25`
```
davieslocalhost:~/work/spark/python$ git diff --find-copies-harder -M25 --numstat master..
2 5 python/docs/pyspark.ml.rst
0 3 python/docs/pyspark.mllib.rst
10 2 python/docs/pyspark.sql.rst
1 1 python/pyspark/mllib/linalg.py
21 14 python/pyspark/{mllib => sql}/__init__.py
14 2108 python/pyspark/{sql.py => sql/context.py}
10 1772 python/pyspark/{sql.py => sql/dataframe.py}
7 6 python/pyspark/{sql_tests.py => sql/tests.py}
8 1465 python/pyspark/{sql.py => sql/types.py}
4 2 python/run-tests
1 1 sql/core/src/main/scala/org/apache/spark/sql/test/ExamplePointUDT.scala
```
Also `git blame -C -C python/pyspark/sql/context.py` to track the history.
Author: Davies Liu <davies@databricks.com>
Closes #4479 from davies/sql and squashes the following commits:
1b5f0a5 [Davies Liu] Merge branch 'master' of github.com:apache/spark into sql
2b2b983 [Davies Liu] restructure pyspark.sql
Diffstat (limited to 'python/pyspark/sql/context.py')
-rw-r--r-- | python/pyspark/sql/context.py | 642 |
1 files changed, 642 insertions, 0 deletions
diff --git a/python/pyspark/sql/context.py b/python/pyspark/sql/context.py new file mode 100644 index 0000000000..49f016a9cf --- /dev/null +++ b/python/pyspark/sql/context.py @@ -0,0 +1,642 @@ +# +# Licensed to the Apache Software Foundation (ASF) under one or more +# contributor license agreements. See the NOTICE file distributed with +# this work for additional information regarding copyright ownership. +# The ASF licenses this file to You under the Apache License, Version 2.0 +# (the "License"); you may not use this file except in compliance with +# the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +import warnings +import json +from array import array +from itertools import imap + +from py4j.protocol import Py4JError + +from pyspark.rdd import _prepare_for_python_RDD +from pyspark.serializers import AutoBatchedSerializer, PickleSerializer +from pyspark.sql.types import StringType, StructType, _verify_type, \ + _infer_schema, _has_nulltype, _merge_type, _create_converter, _python_to_sql_converter +from pyspark.sql.dataframe import DataFrame + +__all__ = ["SQLContext", "HiveContext"] + + +class SQLContext(object): + + """Main entry point for Spark SQL functionality. + + A SQLContext can be used create L{DataFrame}, register L{DataFrame} as + tables, execute SQL over tables, cache tables, and read parquet files. + """ + + def __init__(self, sparkContext, sqlContext=None): + """Create a new SQLContext. + + :param sparkContext: The SparkContext to wrap. + :param sqlContext: An optional JVM Scala SQLContext. If set, we do not instatiate a new + SQLContext in the JVM, instead we make all calls to this object. + + >>> df = sqlCtx.inferSchema(rdd) + >>> sqlCtx.inferSchema(df) # doctest: +IGNORE_EXCEPTION_DETAIL + Traceback (most recent call last): + ... + TypeError:... + + >>> bad_rdd = sc.parallelize([1,2,3]) + >>> sqlCtx.inferSchema(bad_rdd) # doctest: +IGNORE_EXCEPTION_DETAIL + Traceback (most recent call last): + ... + ValueError:... + + >>> from datetime import datetime + >>> allTypes = sc.parallelize([Row(i=1, s="string", d=1.0, l=1L, + ... b=True, list=[1, 2, 3], dict={"s": 0}, row=Row(a=1), + ... time=datetime(2014, 8, 1, 14, 1, 5))]) + >>> df = sqlCtx.inferSchema(allTypes) + >>> df.registerTempTable("allTypes") + >>> sqlCtx.sql('select i+1, d+1, not b, list[1], dict["s"], time, row.a ' + ... 'from allTypes where b and i > 0').collect() + [Row(c0=2, c1=2.0, c2=False, c3=2, c4=0...8, 1, 14, 1, 5), a=1)] + >>> df.map(lambda x: (x.i, x.s, x.d, x.l, x.b, x.time, + ... x.row.a, x.list)).collect() + [(1, u'string', 1.0, 1, True, ...(2014, 8, 1, 14, 1, 5), 1, [1, 2, 3])] + """ + self._sc = sparkContext + self._jsc = self._sc._jsc + self._jvm = self._sc._jvm + self._scala_SQLContext = sqlContext + + @property + def _ssql_ctx(self): + """Accessor for the JVM Spark SQL context. + + Subclasses can override this property to provide their own + JVM Contexts. + """ + if self._scala_SQLContext is None: + self._scala_SQLContext = self._jvm.SQLContext(self._jsc.sc()) + return self._scala_SQLContext + + def registerFunction(self, name, f, returnType=StringType()): + """Registers a lambda function as a UDF so it can be used in SQL statements. + + In addition to a name and the function itself, the return type can be optionally specified. + When the return type is not given it default to a string and conversion will automatically + be done. For any other return type, the produced object must match the specified type. + + >>> sqlCtx.registerFunction("stringLengthString", lambda x: len(x)) + >>> sqlCtx.sql("SELECT stringLengthString('test')").collect() + [Row(c0=u'4')] + >>> from pyspark.sql.types import IntegerType + >>> sqlCtx.registerFunction("stringLengthInt", lambda x: len(x), IntegerType()) + >>> sqlCtx.sql("SELECT stringLengthInt('test')").collect() + [Row(c0=4)] + """ + func = lambda _, it: imap(lambda x: f(*x), it) + ser = AutoBatchedSerializer(PickleSerializer()) + command = (func, None, ser, ser) + pickled_cmd, bvars, env, includes = _prepare_for_python_RDD(self._sc, command, self) + self._ssql_ctx.udf().registerPython(name, + bytearray(pickled_cmd), + env, + includes, + self._sc.pythonExec, + bvars, + self._sc._javaAccumulator, + returnType.json()) + + def inferSchema(self, rdd, samplingRatio=None): + """Infer and apply a schema to an RDD of L{Row}. + + When samplingRatio is specified, the schema is inferred by looking + at the types of each row in the sampled dataset. Otherwise, the + first 100 rows of the RDD are inspected. Nested collections are + supported, which can include array, dict, list, Row, tuple, + namedtuple, or object. + + Each row could be L{pyspark.sql.Row} object or namedtuple or objects. + Using top level dicts is deprecated, as dict is used to represent Maps. + + If a single column has multiple distinct inferred types, it may cause + runtime exceptions. + + >>> rdd = sc.parallelize( + ... [Row(field1=1, field2="row1"), + ... Row(field1=2, field2="row2"), + ... Row(field1=3, field2="row3")]) + >>> df = sqlCtx.inferSchema(rdd) + >>> df.collect()[0] + Row(field1=1, field2=u'row1') + + >>> NestedRow = Row("f1", "f2") + >>> nestedRdd1 = sc.parallelize([ + ... NestedRow(array('i', [1, 2]), {"row1": 1.0}), + ... NestedRow(array('i', [2, 3]), {"row2": 2.0})]) + >>> df = sqlCtx.inferSchema(nestedRdd1) + >>> df.collect() + [Row(f1=[1, 2], f2={u'row1': 1.0}), ..., f2={u'row2': 2.0})] + + >>> nestedRdd2 = sc.parallelize([ + ... NestedRow([[1, 2], [2, 3]], [1, 2]), + ... NestedRow([[2, 3], [3, 4]], [2, 3])]) + >>> df = sqlCtx.inferSchema(nestedRdd2) + >>> df.collect() + [Row(f1=[[1, 2], [2, 3]], f2=[1, 2]), ..., f2=[2, 3])] + + >>> from collections import namedtuple + >>> CustomRow = namedtuple('CustomRow', 'field1 field2') + >>> rdd = sc.parallelize( + ... [CustomRow(field1=1, field2="row1"), + ... CustomRow(field1=2, field2="row2"), + ... CustomRow(field1=3, field2="row3")]) + >>> df = sqlCtx.inferSchema(rdd) + >>> df.collect()[0] + Row(field1=1, field2=u'row1') + """ + + if isinstance(rdd, DataFrame): + raise TypeError("Cannot apply schema to DataFrame") + + first = rdd.first() + if not first: + raise ValueError("The first row in RDD is empty, " + "can not infer schema") + if type(first) is dict: + warnings.warn("Using RDD of dict to inferSchema is deprecated," + "please use pyspark.sql.Row instead") + + if samplingRatio is None: + schema = _infer_schema(first) + if _has_nulltype(schema): + for row in rdd.take(100)[1:]: + schema = _merge_type(schema, _infer_schema(row)) + if not _has_nulltype(schema): + break + else: + warnings.warn("Some of types cannot be determined by the " + "first 100 rows, please try again with sampling") + else: + if samplingRatio > 0.99: + rdd = rdd.sample(False, float(samplingRatio)) + schema = rdd.map(_infer_schema).reduce(_merge_type) + + converter = _create_converter(schema) + rdd = rdd.map(converter) + return self.applySchema(rdd, schema) + + def applySchema(self, rdd, schema): + """ + Applies the given schema to the given RDD of L{tuple} or L{list}. + + These tuples or lists can contain complex nested structures like + lists, maps or nested rows. + + The schema should be a StructType. + + It is important that the schema matches the types of the objects + in each row or exceptions could be thrown at runtime. + + >>> from pyspark.sql.types import * + >>> rdd2 = sc.parallelize([(1, "row1"), (2, "row2"), (3, "row3")]) + >>> schema = StructType([StructField("field1", IntegerType(), False), + ... StructField("field2", StringType(), False)]) + >>> df = sqlCtx.applySchema(rdd2, schema) + >>> sqlCtx.registerRDDAsTable(df, "table1") + >>> df2 = sqlCtx.sql("SELECT * from table1") + >>> df2.collect() + [Row(field1=1, field2=u'row1'),..., Row(field1=3, field2=u'row3')] + + >>> from datetime import date, datetime + >>> rdd = sc.parallelize([(127, -128L, -32768, 32767, 2147483647L, 1.0, + ... date(2010, 1, 1), + ... datetime(2010, 1, 1, 1, 1, 1), + ... {"a": 1}, (2,), [1, 2, 3], None)]) + >>> schema = StructType([ + ... StructField("byte1", ByteType(), False), + ... StructField("byte2", ByteType(), False), + ... StructField("short1", ShortType(), False), + ... StructField("short2", ShortType(), False), + ... StructField("int", IntegerType(), False), + ... StructField("float", FloatType(), False), + ... StructField("date", DateType(), False), + ... StructField("time", TimestampType(), False), + ... StructField("map", + ... MapType(StringType(), IntegerType(), False), False), + ... StructField("struct", + ... StructType([StructField("b", ShortType(), False)]), False), + ... StructField("list", ArrayType(ByteType(), False), False), + ... StructField("null", DoubleType(), True)]) + >>> df = sqlCtx.applySchema(rdd, schema) + >>> results = df.map( + ... lambda x: (x.byte1, x.byte2, x.short1, x.short2, x.int, x.float, x.date, + ... x.time, x.map["a"], x.struct.b, x.list, x.null)) + >>> results.collect()[0] # doctest: +NORMALIZE_WHITESPACE + (127, -128, -32768, 32767, 2147483647, 1.0, datetime.date(2010, 1, 1), + datetime.datetime(2010, 1, 1, 1, 1, 1), 1, 2, [1, 2, 3], None) + + >>> df.registerTempTable("table2") + >>> sqlCtx.sql( + ... "SELECT byte1 - 1 AS byte1, byte2 + 1 AS byte2, " + + ... "short1 + 1 AS short1, short2 - 1 AS short2, int - 1 AS int, " + + ... "float + 1.5 as float FROM table2").collect() + [Row(byte1=126, byte2=-127, short1=-32767, short2=32766, int=2147483646, float=2.5)] + + >>> from pyspark.sql.types import _parse_schema_abstract, _infer_schema_type + >>> rdd = sc.parallelize([(127, -32768, 1.0, + ... datetime(2010, 1, 1, 1, 1, 1), + ... {"a": 1}, (2,), [1, 2, 3])]) + >>> abstract = "byte short float time map{} struct(b) list[]" + >>> schema = _parse_schema_abstract(abstract) + >>> typedSchema = _infer_schema_type(rdd.first(), schema) + >>> df = sqlCtx.applySchema(rdd, typedSchema) + >>> df.collect() + [Row(byte=127, short=-32768, float=1.0, time=..., list=[1, 2, 3])] + """ + + if isinstance(rdd, DataFrame): + raise TypeError("Cannot apply schema to DataFrame") + + if not isinstance(schema, StructType): + raise TypeError("schema should be StructType") + + # take the first few rows to verify schema + rows = rdd.take(10) + # Row() cannot been deserialized by Pyrolite + if rows and isinstance(rows[0], tuple) and rows[0].__class__.__name__ == 'Row': + rdd = rdd.map(tuple) + rows = rdd.take(10) + + for row in rows: + _verify_type(row, schema) + + # convert python objects to sql data + converter = _python_to_sql_converter(schema) + rdd = rdd.map(converter) + + jrdd = self._jvm.SerDeUtil.toJavaArray(rdd._to_java_object_rdd()) + df = self._ssql_ctx.applySchemaToPythonRDD(jrdd.rdd(), schema.json()) + return DataFrame(df, self) + + def registerRDDAsTable(self, rdd, tableName): + """Registers the given RDD as a temporary table in the catalog. + + Temporary tables exist only during the lifetime of this instance of + SQLContext. + + >>> df = sqlCtx.inferSchema(rdd) + >>> sqlCtx.registerRDDAsTable(df, "table1") + """ + if (rdd.__class__ is DataFrame): + df = rdd._jdf + self._ssql_ctx.registerRDDAsTable(df, tableName) + else: + raise ValueError("Can only register DataFrame as table") + + def parquetFile(self, *paths): + """Loads a Parquet file, returning the result as a L{DataFrame}. + + >>> import tempfile, shutil + >>> parquetFile = tempfile.mkdtemp() + >>> shutil.rmtree(parquetFile) + >>> df = sqlCtx.inferSchema(rdd) + >>> df.saveAsParquetFile(parquetFile) + >>> df2 = sqlCtx.parquetFile(parquetFile) + >>> sorted(df.collect()) == sorted(df2.collect()) + True + """ + gateway = self._sc._gateway + jpath = paths[0] + jpaths = gateway.new_array(gateway.jvm.java.lang.String, len(paths) - 1) + for i in range(1, len(paths)): + jpaths[i] = paths[i] + jdf = self._ssql_ctx.parquetFile(jpath, jpaths) + return DataFrame(jdf, self) + + def jsonFile(self, path, schema=None, samplingRatio=1.0): + """ + Loads a text file storing one JSON object per line as a + L{DataFrame}. + + If the schema is provided, applies the given schema to this + JSON dataset. + + Otherwise, it samples the dataset with ratio `samplingRatio` to + determine the schema. + + >>> import tempfile, shutil + >>> jsonFile = tempfile.mkdtemp() + >>> shutil.rmtree(jsonFile) + >>> ofn = open(jsonFile, 'w') + >>> for json in jsonStrings: + ... print>>ofn, json + >>> ofn.close() + >>> df1 = sqlCtx.jsonFile(jsonFile) + >>> sqlCtx.registerRDDAsTable(df1, "table1") + >>> df2 = sqlCtx.sql( + ... "SELECT field1 AS f1, field2 as f2, field3 as f3, " + ... "field6 as f4 from table1") + >>> for r in df2.collect(): + ... print r + Row(f1=1, f2=u'row1', f3=Row(field4=11, field5=None), f4=None) + Row(f1=2, f2=None, f3=Row(field4=22,..., f4=[Row(field7=u'row2')]) + Row(f1=None, f2=u'row3', f3=Row(field4=33, field5=[]), f4=None) + + >>> df3 = sqlCtx.jsonFile(jsonFile, df1.schema()) + >>> sqlCtx.registerRDDAsTable(df3, "table2") + >>> df4 = sqlCtx.sql( + ... "SELECT field1 AS f1, field2 as f2, field3 as f3, " + ... "field6 as f4 from table2") + >>> for r in df4.collect(): + ... print r + Row(f1=1, f2=u'row1', f3=Row(field4=11, field5=None), f4=None) + Row(f1=2, f2=None, f3=Row(field4=22,..., f4=[Row(field7=u'row2')]) + Row(f1=None, f2=u'row3', f3=Row(field4=33, field5=[]), f4=None) + + >>> from pyspark.sql.types import * + >>> schema = StructType([ + ... StructField("field2", StringType(), True), + ... StructField("field3", + ... StructType([ + ... StructField("field5", + ... ArrayType(IntegerType(), False), True)]), False)]) + >>> df5 = sqlCtx.jsonFile(jsonFile, schema) + >>> sqlCtx.registerRDDAsTable(df5, "table3") + >>> df6 = sqlCtx.sql( + ... "SELECT field2 AS f1, field3.field5 as f2, " + ... "field3.field5[0] as f3 from table3") + >>> df6.collect() + [Row(f1=u'row1', f2=None, f3=None)...Row(f1=u'row3', f2=[], f3=None)] + """ + if schema is None: + df = self._ssql_ctx.jsonFile(path, samplingRatio) + else: + scala_datatype = self._ssql_ctx.parseDataType(schema.json()) + df = self._ssql_ctx.jsonFile(path, scala_datatype) + return DataFrame(df, self) + + def jsonRDD(self, rdd, schema=None, samplingRatio=1.0): + """Loads an RDD storing one JSON object per string as a L{DataFrame}. + + If the schema is provided, applies the given schema to this + JSON dataset. + + Otherwise, it samples the dataset with ratio `samplingRatio` to + determine the schema. + + >>> df1 = sqlCtx.jsonRDD(json) + >>> sqlCtx.registerRDDAsTable(df1, "table1") + >>> df2 = sqlCtx.sql( + ... "SELECT field1 AS f1, field2 as f2, field3 as f3, " + ... "field6 as f4 from table1") + >>> for r in df2.collect(): + ... print r + Row(f1=1, f2=u'row1', f3=Row(field4=11, field5=None), f4=None) + Row(f1=2, f2=None, f3=Row(field4=22..., f4=[Row(field7=u'row2')]) + Row(f1=None, f2=u'row3', f3=Row(field4=33, field5=[]), f4=None) + + >>> df3 = sqlCtx.jsonRDD(json, df1.schema()) + >>> sqlCtx.registerRDDAsTable(df3, "table2") + >>> df4 = sqlCtx.sql( + ... "SELECT field1 AS f1, field2 as f2, field3 as f3, " + ... "field6 as f4 from table2") + >>> for r in df4.collect(): + ... print r + Row(f1=1, f2=u'row1', f3=Row(field4=11, field5=None), f4=None) + Row(f1=2, f2=None, f3=Row(field4=22..., f4=[Row(field7=u'row2')]) + Row(f1=None, f2=u'row3', f3=Row(field4=33, field5=[]), f4=None) + + >>> from pyspark.sql.types import * + >>> schema = StructType([ + ... StructField("field2", StringType(), True), + ... StructField("field3", + ... StructType([ + ... StructField("field5", + ... ArrayType(IntegerType(), False), True)]), False)]) + >>> df5 = sqlCtx.jsonRDD(json, schema) + >>> sqlCtx.registerRDDAsTable(df5, "table3") + >>> df6 = sqlCtx.sql( + ... "SELECT field2 AS f1, field3.field5 as f2, " + ... "field3.field5[0] as f3 from table3") + >>> df6.collect() + [Row(f1=u'row1', f2=None,...Row(f1=u'row3', f2=[], f3=None)] + + >>> sqlCtx.jsonRDD(sc.parallelize(['{}', + ... '{"key0": {"key1": "value1"}}'])).collect() + [Row(key0=None), Row(key0=Row(key1=u'value1'))] + >>> sqlCtx.jsonRDD(sc.parallelize(['{"key0": null}', + ... '{"key0": {"key1": "value1"}}'])).collect() + [Row(key0=None), Row(key0=Row(key1=u'value1'))] + """ + + def func(iterator): + for x in iterator: + if not isinstance(x, basestring): + x = unicode(x) + if isinstance(x, unicode): + x = x.encode("utf-8") + yield x + keyed = rdd.mapPartitions(func) + keyed._bypass_serializer = True + jrdd = keyed._jrdd.map(self._jvm.BytesToString()) + if schema is None: + df = self._ssql_ctx.jsonRDD(jrdd.rdd(), samplingRatio) + else: + scala_datatype = self._ssql_ctx.parseDataType(schema.json()) + df = self._ssql_ctx.jsonRDD(jrdd.rdd(), scala_datatype) + return DataFrame(df, self) + + def sql(self, sqlQuery): + """Return a L{DataFrame} representing the result of the given query. + + >>> df = sqlCtx.inferSchema(rdd) + >>> sqlCtx.registerRDDAsTable(df, "table1") + >>> df2 = sqlCtx.sql("SELECT field1 AS f1, field2 as f2 from table1") + >>> df2.collect() + [Row(f1=1, f2=u'row1'), Row(f1=2, f2=u'row2'), Row(f1=3, f2=u'row3')] + """ + return DataFrame(self._ssql_ctx.sql(sqlQuery), self) + + def table(self, tableName): + """Returns the specified table as a L{DataFrame}. + + >>> df = sqlCtx.inferSchema(rdd) + >>> sqlCtx.registerRDDAsTable(df, "table1") + >>> df2 = sqlCtx.table("table1") + >>> sorted(df.collect()) == sorted(df2.collect()) + True + """ + return DataFrame(self._ssql_ctx.table(tableName), self) + + def cacheTable(self, tableName): + """Caches the specified table in-memory.""" + self._ssql_ctx.cacheTable(tableName) + + def uncacheTable(self, tableName): + """Removes the specified table from the in-memory cache.""" + self._ssql_ctx.uncacheTable(tableName) + + +class HiveContext(SQLContext): + + """A variant of Spark SQL that integrates with data stored in Hive. + + Configuration for Hive is read from hive-site.xml on the classpath. + It supports running both SQL and HiveQL commands. + """ + + def __init__(self, sparkContext, hiveContext=None): + """Create a new HiveContext. + + :param sparkContext: The SparkContext to wrap. + :param hiveContext: An optional JVM Scala HiveContext. If set, we do not instatiate a new + HiveContext in the JVM, instead we make all calls to this object. + """ + SQLContext.__init__(self, sparkContext) + + if hiveContext: + self._scala_HiveContext = hiveContext + + @property + def _ssql_ctx(self): + try: + if not hasattr(self, '_scala_HiveContext'): + self._scala_HiveContext = self._get_hive_ctx() + return self._scala_HiveContext + except Py4JError as e: + raise Exception("You must build Spark with Hive. " + "Export 'SPARK_HIVE=true' and run " + "build/sbt assembly", e) + + def _get_hive_ctx(self): + return self._jvm.HiveContext(self._jsc.sc()) + + +def _create_row(fields, values): + row = Row(*values) + row.__FIELDS__ = fields + return row + + +class Row(tuple): + + """ + A row in L{DataFrame}. The fields in it can be accessed like attributes. + + Row can be used to create a row object by using named arguments, + the fields will be sorted by names. + + >>> row = Row(name="Alice", age=11) + >>> row + Row(age=11, name='Alice') + >>> row.name, row.age + ('Alice', 11) + + Row also can be used to create another Row like class, then it + could be used to create Row objects, such as + + >>> Person = Row("name", "age") + >>> Person + <Row(name, age)> + >>> Person("Alice", 11) + Row(name='Alice', age=11) + """ + + def __new__(self, *args, **kwargs): + if args and kwargs: + raise ValueError("Can not use both args " + "and kwargs to create Row") + if args: + # create row class or objects + return tuple.__new__(self, args) + + elif kwargs: + # create row objects + names = sorted(kwargs.keys()) + values = tuple(kwargs[n] for n in names) + row = tuple.__new__(self, values) + row.__FIELDS__ = names + return row + + else: + raise ValueError("No args or kwargs") + + def asDict(self): + """ + Return as an dict + """ + if not hasattr(self, "__FIELDS__"): + raise TypeError("Cannot convert a Row class into dict") + return dict(zip(self.__FIELDS__, self)) + + # let obect acs like class + def __call__(self, *args): + """create new Row object""" + return _create_row(self, args) + + def __getattr__(self, item): + if item.startswith("__"): + raise AttributeError(item) + try: + # it will be slow when it has many fields, + # but this will not be used in normal cases + idx = self.__FIELDS__.index(item) + return self[idx] + except IndexError: + raise AttributeError(item) + + def __reduce__(self): + if hasattr(self, "__FIELDS__"): + return (_create_row, (self.__FIELDS__, tuple(self))) + else: + return tuple.__reduce__(self) + + def __repr__(self): + if hasattr(self, "__FIELDS__"): + return "Row(%s)" % ", ".join("%s=%r" % (k, v) + for k, v in zip(self.__FIELDS__, self)) + else: + return "<Row(%s)>" % ", ".join(self) + + +def _test(): + import doctest + from pyspark.context import SparkContext + from pyspark.sql import Row, SQLContext + import pyspark.sql.context + globs = pyspark.sql.context.__dict__.copy() + sc = SparkContext('local[4]', 'PythonTest') + globs['sc'] = sc + globs['sqlCtx'] = sqlCtx = SQLContext(sc) + globs['rdd'] = sc.parallelize( + [Row(field1=1, field2="row1"), + Row(field1=2, field2="row2"), + Row(field1=3, field2="row3")] + ) + jsonStrings = [ + '{"field1": 1, "field2": "row1", "field3":{"field4":11}}', + '{"field1" : 2, "field3":{"field4":22, "field5": [10, 11]},' + '"field6":[{"field7": "row2"}]}', + '{"field1" : null, "field2": "row3", ' + '"field3":{"field4":33, "field5": []}}' + ] + globs['jsonStrings'] = jsonStrings + globs['json'] = sc.parallelize(jsonStrings) + (failure_count, test_count) = doctest.testmod( + pyspark.sql.context, globs=globs, optionflags=doctest.ELLIPSIS) + globs['sc'].stop() + if failure_count: + exit(-1) + + +if __name__ == "__main__": + _test() |