format (DataStreamReader)

Specifies the input data source format.

Syntax

format(source)

Parameters

Parameter Type Description
source str Name of the data source, for example 'json' or 'parquet'.

Returns

DataStreamReader

Examples

spark.readStream.format("text")
# <...streaming.readwriter.DataStreamReader object ...>

Write a text file and read it back as a stream:

import tempfile
import time
with tempfile.TemporaryDirectory(prefix="format") as d:
    spark.createDataFrame(
        [("hello",), ("this",)]).write.mode("overwrite").format("text").save(d)
    q = spark.readStream.format("text").load(d).writeStream.format("console").start()
    time.sleep(3)
    q.stop()