What is StreamingContext?

Asked By: Jader Kruell | Last Updated: 8th January, 2020
Category: technology and computing data storage and warehousing
4.3/5 (61 Views . 36 Votes)
public class StreamingContext extends Object implements Logging. Main entry point for Spark Streaming functionality. It provides methods used to create DStream s from various input sources. It can be either created by providing a Spark master URL and an appName, or from a org. apache.

Click to see full answer


Also know, what is spark streaming used for?

Spark Streaming is an extension of the core Spark API that allows data engineers and data scientists to process real-time data from various sources including (but not limited to) Kafka, Flume, and Amazon Kinesis. This processed data can be pushed out to file systems, databases, and live dashboards.

One may also ask, which of the following sources can spark streaming receive data? Spark Streaming supports data sources such as HDFS directories, TCP sockets, Kafka, Flume, Twitter, etc. Data Streams can be processed with Spark's core APIS, DataFrames SQL, or machine learning APIs, and can be persisted to a filesystem, HDFS, databases, or any data source offering a Hadoop OutputFormat.

Considering this, what is spark Kafka?

Kafka is a potential messaging and integration platform for Spark streaming. Kafka act as the central hub for real-time streams of data and are processed using complex algorithms in Spark Streaming.

What is a batch interval?

Batch Interval (aka batchDuration) Batch Interval is a property of a Streaming application that describes how often an RDD of input records is generated. It is the time to collect input records before they become a micro-batch.

31 Related Question Answers Found

What is difference between Kafka and spark?

Data Flow: Kafka vs Spark provide real-time data streaming from source to target. Kafka just Flow the data to the topic, Spark is procedural data flow. Data Processing: We cannot perform any transformation on data wherein Spark we can transform the data.

What is the use of spark?

Spark is a general-purpose distributed data processing engine that is suitable for use in a wide range of circumstances. On top of the Spark core data processing engine, there are libraries for SQL, machine learning, graph computation, and stream processing, which can be used together in an application.

What is the difference between Kafka and storm?

Kafka and Storm have a slightly different purpose: Kafka is a distributed message broker which can handle big amount of messages per second. Storm is a scalable, fault-tolerant, real-time analytic system (think like Hadoop in realtime). It consumes data from sources (Spouts) and passes it to pipeline (Bolts).

What is Dstreams?

DStream is a sequence of data arriving over time. > Each DStream is represented as a sequence of RDDs arriving at repeated / configured time steps. > DStream can created from various input sources like TCP Sockets, Kafka, Flume, HDFS etc.

How do I stop spark streaming?


If all you need is just stop running streaming application, then simplest way is via Spark admin UI (you can find it's URL in the startup logs of Spark master). There is a section in the UI, that shows running streaming applications, and there are tiny (kill) url buttons near each application ID.

What is spark ETL?

Apache Spark™ is a unified analytics engine for large-scale data processing. In short, Apache Spark is a framework which is used for processing, querying and analyzing Big data. Easy to use as you can write Spark applications in Python, R, and Scala. It provides libraries for SQL, Steaming and Graph computations.

What is DStream in spark streaming?

Spark DStream (Discretized Stream) is the basic abstraction of Spark Streaming. It can also be a data stream generated by transforming the input stream. At its core, DStream is a continuous stream of RDD (Spark abstraction). Every RDD in DStream contains data from the certain interval.

What is a sliding interval?

sliding interval - is amount of time in seconds for how much the window will shift. For example in previous example sliding interval is 1 (since calculation is kicked out each second) e.g. at time=1, time=2, time=3 if you set sliding interval=2, you will get calculation at time=1, time=3, time=5

What is Kafka and how it works?

How does it work? Applications (producers) send messages (records) to a Kafka node (broker) and said messages are processed by other applications called consumers. Said messages get stored in a topic and consumers subscribe to the topic to receive new messages.

Why do we use Kafka?


Kafka is used for real-time streams of data, used to collect big data or to do real time analysis or both). Kafka is used with in-memory microservices to provide durability and it can be used to feed events to CEP (complex event streaming systems), and IOT/IFTTT style automation systems.

What is Kafka and why it is used?

Kafka is a distributed streaming platform that is used publish and subscribe to streams of records. Kafka is used for fault tolerant storage. Kafka replicates topic log partitions to multiple servers. Kafka is designed to allow your apps to process records as they occur. Kafka is used for decoupling data streams.

Is Kafka open source?

Apache Kafka is an open-source stream-processing software platform developed by LinkedIn and donated to the Apache Software Foundation, written in Scala and Java. The project aims to provide a unified, high-throughput, low-latency platform for handling real-time data feeds.

Does Kafka use HDFS?

Frameworks like Kafka or Spark are not dependent on Hadoop, they are independent entities. Spark supports Hadoop, like Yarn, can be used for Spark's Cluster mode, HDFS for storage. Same way Kafka as an independent entity, can work with Spark. It stores its messages in the local file system.

What is the current version of Spark streaming available?

History
Version Original release date Latest version
2.1 2016-12-28 2.1.3
2.2 2017-07-11 2.2.3
2.3 2018-02-28 2.3.3
2.4 2018-11-02 2.4.4

What is spark batch?


Spark Streaming receives live input data streams and divides the data into batches, which are then processed by the Spark engine to generate the final stream of results in batches. Spark Streaming provides a high-level abstraction called discretized stream or DStream, which represents a continuous stream of data.

What is data pipeline in spark?

A data pipeline is a software that consolidates data from multiple sources and makes it available to be used strategically.

What is spark cluster?

Cluster is nothing but a platform to install Spark. Apache Spark is an engine for Big Data processing. One can run Spark on distributed mode on the cluster. In the cluster, there is master and n number of workers. It schedules and divides resource in the host machine which forms the cluster.