pyspark.RDD.saveAsNewAPIHadoopDataset¶
-
RDD.
saveAsNewAPIHadoopDataset
(conf: Dict[str, str], keyConverter: Optional[str] = None, valueConverter: Optional[str] = None) → None[source]¶ Output a Python RDD of key-value pairs (of form
RDD[(K, V)]
) to any Hadoop file system, using the new Hadoop OutputFormat API (mapreduce package). Keys/values are converted for output using either user specified converters or, by default, “org.apache.spark.api.python.JavaToWritableConverter”.New in version 1.1.0.
- Parameters
- confdict
Hadoop job configuration
- keyConverterstr, optional
fully qualified classname of key converter (None by default)
- valueConverterstr, optional
fully qualified classname of value converter (None by default)
See also
Examples
>>> import os >>> import tempfile
Set the related classes
>>> output_format_class = "org.apache.hadoop.mapreduce.lib.output.SequenceFileOutputFormat" >>> input_format_class = "org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat" >>> key_class = "org.apache.hadoop.io.IntWritable" >>> value_class = "org.apache.hadoop.io.Text"
>>> with tempfile.TemporaryDirectory() as d: ... path = os.path.join(d, "new_hadoop_file") ... ... # Create the conf for writing ... write_conf = { ... "mapreduce.job.outputformat.class": (output_format_class), ... "mapreduce.job.output.key.class": key_class, ... "mapreduce.job.output.value.class": value_class, ... "mapreduce.output.fileoutputformat.outputdir": path, ... } ... ... # Write a temporary Hadoop file ... rdd = sc.parallelize([(1, ""), (1, "a"), (3, "x")]) ... rdd.saveAsNewAPIHadoopDataset(conf=write_conf) ... ... # Create the conf for reading ... read_conf = {"mapreduce.input.fileinputformat.inputdir": path} ... ... # Load this Hadoop file as an RDD ... loaded = sc.newAPIHadoopRDD(input_format_class, ... key_class, value_class, conf=read_conf) ... sorted(loaded.collect()) [(1, ''), (1, 'a'), (3, 'x')]