Overview

• Node.js Buffer Class Overview
• Buffer Creation
• Buffer Methods
• Buffers and Character Encodings
• Static Methods and Properties
• TypedArray Compatibility
• Handling Binary Data
• Safety Considerations
• Blob Support
• Deprecation of Older APIs

Node.js Buffer Class Overview

The Node.js Buffer class is a global class that provides a way to work with binary data. Here's a summary of its main features and usage:

Buffer Creation

• Buffer.alloc(size): Creates a zero-filled buffer of size bytes.
• Buffer.allocUnsafe(size): Creates an uninitialized buffer of size bytes (faster but may contain old data).
• Buffer.from(array): Creates a buffer from an array of byte values.
• Buffer.from(buffer): Creates a buffer by copying another buffer.
• Buffer.from(string[, encoding]): Creates a buffer by encoding a string using the specified encoding (default is 'utf8').

Buffer Methods

• .toString([encoding[, start[, end]]]): Converts the buffer to a string with the specified encoding.
• .fill(value[, offset[, end]][, encoding]): Fills the buffer with the specified value.
• .equals(otherBuffer): Compares if two buffers are equal.
• .indexOf(value[, byteOffset][, encoding]): Finds the index of a value in the buffer.
• .copy(targetBuffer[, targetStart[, sourceStart[, sourceEnd]]]): Copies data from one buffer to another.

Buffers and Character Encodings

Node.js supports several character encodings such as 'utf8', 'utf16le', 'latin1', 'base64', and 'hex'. When converting between Buffers and strings, specify the desired encoding.

Static Methods and Properties

• Buffer.isBuffer(obj): Checks if an object is a Buffer.
• Buffer.byteLength(string[, encoding]): Returns the byte length of a string.
• Buffer.concat(list[, totalLength]): Concatenates a list of buffers into a single buffer.

TypedArray Compatibility

• Buffer instances are also Uint8Array instances. They share the same methods and properties, such as .length, .subarray(), and indexing (buffer[index]).

Handling Binary Data

• Buffers are particularly useful for reading and writing binary data in streams, manipulating image data, interacting with the file system, or handling network communications.

Safety Considerations

• Buffer.allocUnsafe() and Buffer.allocUnsafeSlow() create buffers faster but may contain old, potentially sensitive data. Use Buffer.alloc() for more secure buffer allocation.

Blob Support

• Node.js v16.7.0 and later support the Blob class, allowing for efficient and safe handling of binary data for use in cases like file I/O.

Deprecation of Older APIs

• The use of new Buffer() constructor is deprecated. Use Buffer.from(), Buffer.alloc(), and Buffer.allocUnsafe() instead.