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javaphpuuidguid

PHP equivalent of getLeastSignificantBits() & getMostSignificantBits from Java?

I'm working with UUIDs in PHP and I have to query a database that stores the most significant bits and least significant bits of a UUID in two separate columns. I found this question for Python, which seems like exactly what I'd need in PHP, but I don't know how to convert the code, and I've never been great with byte manipulation.

What would the equivalent functions for getLeastSignificantBits() and getMostSignificantBits() be in PHP? Thanks!

Edit: Example data (if helpful):

UUID: b33ac8a9-ae45-4120-bb6e-7537e271808e

...should convert to...

Upper Bits: -5531888561172430560
Lower Bits: -4940882858296115058
Solution

  • You simply need two libraries and bcmath extension, using

    composer require ramsey/uuid moontoast/math.

    Parse UUID using Ramsey\Uuid\Uuid:

    $uuid = \Ramsey\Uuid\Uuid::fromString('b33ac8a9-ae45-4120-bb6e-7537e271808e');
echo 'Upper Bits: ' . $uuid->getMostSignificantBits() . "\n";
echo 'Lower Bits: ' . $uuid->getLeastSignificantBits() . "\n";

    You get:

    Upper Bits: 12914855512537121056
Lower Bits: 13505861215413436558

    Using those methods you get Moontoast\Math\BigNumber object, so you can get it's value or convert to different bases:

    $higher = $uuid->getMostSignificantBits();
echo 'Upper Bits 10-base: ' . $higher->getValue() . "\n";
echo 'Upper Bits hex: ' . $higher->convertToBase(16) . "\n";

    You get:

    Upper Bits 10-base: 12914855512537121056
Upper Bits hex: b33ac8a9ae454120

    You can also use $uuid->getMostSignificantBitsHex() and $uuid->getLeastSignificantBitsHex() which are already converted to hex.