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by Danny

•04 February, 2025

Globally Unique Identifiers (GUIDs) or Universally Unique Identifiers (UUIDs) are essential in software development for creating unique values across systems. They are commonly used for database keys, session identifiers, or tracking entities in distributed systems where uniqueness without central coordination is crucial. GUIDs/UUIDs offer a standardised, efficient way of ensuring that values remain unique, even across different systems and environments.

Problem

When building systems that require unique identifiers, relying on sequential IDs (e.g., auto-incremented numbers) can lead to issues such as conflicts during data integration, predictability, or scalability concerns in distributed systems.

Solution

###Using Built-In Libraries Most programming languages provide built-in support for generating GUIDs/UUIDs. These libraries often adhere to the official RFC9562 specification, ensuring compliance and uniqueness.


_10// Install the 'uuid' package first: npm install uuid
_10const { v4: uuidv4 } = require('uuid');
_10
_10// Generate a UUID (Version 4 - random-based)
_10const uniqueIdentifier = uuidv4();
_10console.log('Generated UUID:', uniqueIdentifier);
_10
_10// Example output: "b798f24d-3e53-4142-85ce-14e161b12281"

Use uuid v4 for random identifiers. The commonly used Math.random() function in JavaScript is not robust enough for cryptographic or reliably unique IDs.

Custom UUID Generation

If you need a custom implementation (e.g., to meet specific constraints like length or format), you can create a UUID manually. However, this method requires caution to avoid collisions.


_11function generateCustomUUID() {
_11  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function (char) {
_11    const random = (Math.random() * 16) | 0;
_11    const value = char === 'x' ? random : (random & 0x3) | 0x8; // Ensure 'y' stays in the range [8, b]
_11    return value.toString(16); // Convert to hexadecimal
_11  });
_11}
_11
_11console.log('Custom UUID:', generateCustomUUID());
_11
_11// Example output: "abd6f140-0c65-4a57-b12d-3cbe7af1c0a2"

Validate that your implementation avoids collisions, especially in high-scale/parallel systems.

Randomness Source: Using a cryptographically secure random number generator (e.g., crypto.getRandomValues in JavaScript or os.urandom in Python) is crucial for secure identifier generation.
Version Variants: GUID/UUID versions (e.g., v1, v4) have different use cases. Use v4 for most scenarios unless you need time-based or name-based identifiers.
Library Trust: When using third-party libraries, ensure they are well-maintained and widely adopted.

Further Considerations

Performance: Generating large numbers of UUIDs rapidly, or in highly parallelised systems, may cause performance issues. Consider strategies like caching pre-generated IDs or optimised algorithms such as UUID v4.
Security: UUIDs are not inherently cryptographically secure unless generated using secure random number generation. Avoid exposing GUIDs openly if they could reveal sensitive system details or patterns.

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Problem

Solution

Custom UUID Generation

Further Considerations

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Problem

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Custom UUID Generation

Further Considerations

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