Apache Kafka: -

Apache Kafka is a distributed streaming platform developed by LinkedIn and later open-sourced as an Apache Software Foundation project. It is designed to handle real-time data feeds and processing pipelines. Kafka is used for building real-time data pipelines and streaming applications. It is capable of handling high volumes of data and provides features like fault tolerance, scalability, and durability. At its core, Kafka is a distributed messaging system that allows producers to publish streams of records, and consumers to subscribe to these streams, process them in real-time, and store them in various data systems or perform analytics.

Key aspects of Apache Kafka: - 

Topics: Kafka topics are the feeds of messages in categories. Producers write data to topics and consumers read data from topics.

Partitions: Topics can be divided into partitions, which allows for parallel processing and scalability. Each partition is ordered, and messages within a partition are assigned an offset.

Brokers: Kafka brokers are servers responsible for storing and managing the topic partitions. They handle the storage, replication, and distribution of data across the cluster.

Producers: Producers are applications that publish data to Kafka topics. They write data to Kafka brokers, which then distribute it across partitions.

Consumers: Consumers are applications that subscribe to Kafka topics and process the data. They read data from partitions and can be part of a consumer group for load balancing and fault tolerance.

Consumer Groups: Consumers can be organized into consumer groups, where each group reads data from a topic partition. This allows for parallel processing and scaling of consumer applications.

Kafka as a giant library where books (messages) from different authors (producers) are stored. Each book belongs to a specific section (topic) in the library and is placed on a shelf (partition) alongside other books in that section. The books on each shelf are arranged in order of when they were placed there (offset), and each book has a timestamp to show when it was added. Visitors (consumers) can come to the library and read books from any section they're interested in. Additionally, Kafka has a special service where people can write down their thoughts about the books they've read and leave them in the library for others to see (Streams API). This service helps people share their insights and ideas with each other. The library is managed by a team of librarians (brokers) who make sure the books are organized correctly and that there are copies of popular books on multiple shelves (partition replication) to ensure they're always available, even if one shelf gets too crowded or breaks. With Kafka's transactional feature, it's like the librarians can ensure that when someone borrows a book and returns it, it's done exactly once, without any mistakes. This makes the  whole borrowing and returning process smoother and more reliable.

Apache Kafka as a sophisticated post office. In this post office, you can set up different mailboxes (topics) for various types of mail (messages). You can send letters (messages) to these mailboxes about anything, from a notification on your blog to a simple text that triggers another action. Kafka Broker In a Kafka setup, you have several servers (called Kafka brokers) acting as the post office workers. These brokers manage everything. There are senders (producers) who drop their letters (messages) into the appropriate mailboxes (topics) managed by these brokers. On the other side, you have receivers (consumers) who pick up the letters (messages) from the mailboxes (topics) they are interested in.

 

Topic Partition: Kafka topics are split into smaller pieces called partitions. This lets you spread data across different servers.

Consumer Group: This is a group of consumers (applications) that read messages from the same topic together.

Node: A single computer in a Kafka cluster.

Replicas: Backups of partitions that don't read or write data but are there to prevent data loss.

Producer: An application that sends messages.

Consumer: An application that receives messages.

 

Real-Time Applications

  • Twitter: Users post and read tweets. Twitter uses Kafka and Storm to process these tweets in real-time.
  • LinkedIn: Uses Kafka to handle data streams for activity updates and metrics. This powers features like the LinkedIn Newsfeed and supports their analytics systems.
  • Netflix: Uses Kafka to monitor and process events in real-time for their streaming services.
  • Box: Uses Kafka for analytics and real-time monitoring.

Apache Kafka is a distributed streaming platform designed to handle high-throughput, low-latency data streams. It is widely used for building real-time data pipelines and streaming applications. Kafka is highly scalable, fault-tolerant, and designed for distributed data processing.

Key Components

  1. Topics:
    • Topics are categories or feed names to which records are sent.
    • A topic is split into partitions to enable parallel processing.
  2. Partitions:
    • Each topic is divided into partitions.
    • Partitions allow Kafka to scale horizontally and enable data parallelism.
    • Messages within a partition are ordered by their offset.
  3. Brokers:
    • Kafka brokers are servers that store data and serve client requests.
    • A Kafka cluster is made up of multiple brokers.
    • Brokers handle the storage, replication, and distribution of partitioned data.
  4. Producers:
    • Producers publish messages to Kafka topics.
    • They can send messages to specific partitions based on a key.
  5. Consumers:
    • Consumers subscribe to Kafka topics and process the published messages.
    • Consumers can be part of a consumer group for load balancing.
  6. Consumer Groups:
    • A consumer group is a set of consumers working together to consume messages from a topic.
    • Each consumer in a group processes data from a unique set of partitions.
  7. Replicas:
    • Kafka maintains replicas of partitions to ensure data availability and fault tolerance.
    • Only one replica is designated as the leader and handles all reads and writes. The others are followers.
  8. ZooKeeper:
    • Apache Zookeeper is used to manage and coordinate Kafka brokers.
    • It handles leader election, configuration management, and synchronization.

Kafka Architecture

Kafka's architecture is designed for scalability and high availability:

  • Producers send data to Kafka topics.
  • Brokers store and manage data partitions.
  • Consumers read data from topics.

Each broker in a Kafka cluster can handle data partitions and balance the load across the cluster. Partitions can be replicated across multiple brokers to ensure data durability and availability.

Key Features

  1. Scalability:
    • Kafka can scale horizontally by adding more brokers to the cluster.
    • Topics can be partitioned to enable parallel processing.
  2. Durability:
    • Kafka uses distributed commit log storage, which ensures data is written to disk and replicated.
    • This guarantees data durability and fault tolerance.
  3. High Throughput:
    • Kafka can handle high throughput and large volumes of data with low latency.
    • It achieves this through efficient data compression, batching, and zero-copy principles.
  4. Stream Processing:
    • Kafka Streams API allows building real-time applications that process data streams.
    • Kafka integrates with other stream processing frameworks like Apache Flink, Apache Storm, and Apache Spark.
  5. Exactly-Once Semantics:
    • Kafka provides transactional support to ensure exactly-once processing semantics.
    • This is crucial for financial and other critical applications.
  6. Integration:
    • Kafka integrates seamlessly with Hadoop, Spark, Flink, and other big data ecosystems.
    • It supports a variety of client libraries for different programming languages.

How Kafka works: -

  1. Message Production:
    • Producers send messages to Kafka topics.
    • Messages can be keyed to ensure they go to specific partitions.
  2. Message Storage:
    • Kafka stores messages in partitions on disk.
    • Each partition is replicated across multiple brokers for redundancy.
  3. Message Consumption:
    • Consumers subscribe to topics and read messages from partitions.
    • Each consumer in a group reads from different partitions for parallel processing.
  4. Data Processing:
    • Kafka Streams API allows building applications that process and analyze data streams in real-time.
    • External frameworks like Apache Flink and Apache Spark can also be used for stream processing.
  5. Transactional Support:
    • Kafka supports transactions to ensure that messages are processed exactly once.
    • This prevents data loss and duplication, ensuring data consistency.
  6. Durability and Reliability:
  • Kafka ensures data durability by persisting messages to disk.
  • Data replication across multiple brokers ensures fault tolerance.

   7.Exactly-Once Semantics (EOS):

  • Ensures that messages are neither lost nor duplicated, providing strong guarantees for data processing.

Kafka Ecosystem

  • Kafka Connect: A framework for integrating Kafka with external systems, providing source and sink connectors.
  • Kafka Streams: A client library for building real-time stream processing applications.
  • Kafka REST Proxy: Allows HTTP-based interaction with Kafka, making it easier to integrate with web applications.
  • Schema Registry: Manages and enforces data schemas for Kafka topics, ensuring data compatibility and evolution.

 

Kafka's architecture consists of several key components:

  1. Cluster: A Kafka cluster comprises multiple brokers working together to ensure data replication and fault tolerance.
  2. ZooKeeper: Originally used for managing and coordinating Kafka brokers. Kafka is moving towards a ZooKeeper-less architecture with the introduction of KRaft (Kafka Raft Metadata mode).

 

Use Cases

  1. Real-Time Analytics:
    • Companies use Kafka to process and analyze real-time data streams for insights and decision-making.
  2. Event Sourcing:
    • Kafka acts as a source of truth for events, allowing systems to reconstruct states based on event logs.
  3. Log Aggregation:
    • Kafka collects and aggregates logs from various services, centralizing log management.
  4. Data Integration:
    • Kafka connects different data sources and sinks, facilitating seamless data flow across systems.

 

Conclusion

Apache Kafka is a robust and versatile platform for handling real-time data streams. Its ability to scale, combined with high throughput and low latency, makes it a preferred choice for many large-scale, data-intensive applications. By providing strong guarantees around data durability and fault tolerance, Kafka ensures that data is processed reliably and efficiently.



Contact Us logo Whatsapp