Questions
5 of 24
1What are streams?
2List elementary stream types.
3What are advantages of streams.
4Create a readable stream
5How can you create a custom Transform stream in Node.js?
6What is the `end` event in a readable stream, and how is it different from the `finish` event in a writable stream?
7How can you handle errors in Node.js streams?
8Explain the concept of object streams and provide an example use case.
9Explain the difference between `ObjectMode` and `Buffer` mode in a readable stream.
10Explain the difference between a flowing and a non-flowing readable stream.
11What is the difference between the `data` event and the `readable` event in a readable stream?
12How can you handle cleanup operations when working with streams?
13What is the purpose of the `highWaterMark` option when creating a readable stream?
14What is backpressure in Node.js streams, and how can you handle it?
15What is the pause() method used for in a readable stream, and how can you resume data flow?
16What is the purpose of the `stream.finished()` utility in Node.js?
17How do you handle stream errors when working with async/await in Node.js?
18How can you handle memory usage when dealing with large files in Node.js streams?
19Explain the concept of piping in Node.js streams.
20What is the purpose of pipeThrough function
21What is the purpose of the `unpipe()` method in Node.js streams, and how does it work?
22Explain the difference between `pipe()` and `on('data')` when working with streams.
23What is the purpose of the `stream.pipeline()` function in Node.js?
24write code of a stream to read a local file in node js
nodejsnodejs
Basics
Event Loop
Buffers
Streams
Events
Time functions
Clusters
Crypto
Modules
Worker Threads
File Operations
Threads
Performance Optimisation
Websockets
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How can you create a custom Transform stream in Node.js?

By extending the Transform class from the stream module and implementing the _transform method to define how data should be transformed.

You can define a class that extends the class and implement the method to specify how the data is transformed.
You can now use your custom Transform stream by piping data through it:
The _transform(chunk, encoding, callback) method:
  1. 1

    Handles the transformation logic for each chunk of data.

  2. 2

    chunk is the current piece of data being transformed.

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    callback is called when the transformation is complete.

The _flush(callback) method:
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    Optional: It allows you to perform any cleanup or final transformations when the stream ends.