better_uuid

Description:

better uuid

better_uuid #
A better uuid package for the dart language
Getting Started #
Include better_uuid in your project by editing the dependencies of your dart project's pubspec.yaml
dependencies:

better_uuid: ^0.1.2
copied to clipboard
Usage #
Version 1 UUID #
import 'package:better_uuid/uuid.dart';

var id = Uuid.v1(); // Uuid object
print(id.time); // 137671473757059390
print(id.version); // 1
print(id.variant); // UuidVariant.rfc4122
print(id.clockSeq); // 12781
print(id.node); // 56765789678
copied to clipboard
Note: Dart does not currently support getting the MAC address of a device in an easy way, so the node variable for version 1 UUIDs is randomly generated the very first time a version 1 UUID is requested, and is kept consistent throughout the life of the program.
Parameters can be passed to version 1 UUIDs if you want the same values used in multiple UUIDs
Version 1 with consistent node (perhaps to ensure the same node value in different program lives):
node = 67985654;
var id1 = Uuid.v1(node: node);
print(id1.toString()); // e34ae8a2-1b86-11e9-a108-0000040d60f6
var id2 = Uuid.v1(node: node);
print(id2.toString()); // e34b0fc6-1b86-11e9-a108-0000040d60f6
copied to clipboard
Version 1 Recreation
var timestamp = 839523850982;
var clockSequence = 2765;
var node = 9875626547;
var id = Uuid.v1(timestamp: timestamp, clockSequence: clockSequence, node: node, recreation: true);
copied to clipboard
If all three numeric parameters, timestamp, clockSequence, and node are given, you should also specify recreation: true
If recreation is left as false and the timestamp is less than the current timestamp in UuidConfig.currentTimestamp, the clock sequence will be incremented and the UUID will be different.
Version 3 and 5 UUID #
Version 3 and 5 UUIDs are made by taking in 2 required paramters:

namespace -- List
name -- String

var same1 = Uuid.v3(Uuid.namespaceDns, 'http://example.com');
var same2 = Uuid.v3(Uuid.namespaceDns, 'http://example.com');

assert(same1 == same2);
copied to clipboard
var same1 = Uuid.v5(Uuid.namespaceOid, 'http://test.com');
var same2 = Uuid.v5(Uuid.namespaceOid, 'http://test.com');

assert(same1 == same2);
copied to clipboard
Default Namespaces Given by RFC 4122: Uuid.namespaceDns, Uuid.namespaceUrl, Uuid.namespaceOid, Uuid.namespaceX500
Any byte list can be used for the namespace parameter, not just the ones listed above.
Version 4 UUID #
All variables of the version 4 UUID are randomly generated with Random.secure()
Uuid id = Uuid.v4();
Uuid diff = Uuid.v4();

print(id.version); // 4
assert(id != diff);
copied to clipboard
Version 4 UUIDs are typically preferred over any other version
String conversion #
From String to Uuid
UUIDs can be created from a given string in any number of formats:
var id1 = Uuid('c860fcd8-19ec-11e9-a9cd-6045cb34583b');
var id2 = Uuid('{c860fcd8-19ec-11e9-a9cd-6045cb34583b}');
var id3 = Uuid('{c860fcd819ec11e9a9cd6045cb34583b}');
var id4 = Uuid('c860fcd819ec11e9a9cd6045cb34583b');
var id5 = Uuid('urn:uuid:40e1217c-9cf7-47f9-b6c6-7046ec76e7be');
copied to clipboard
From Uuid to String
var id = Uuid('c860fcd8-19ec-11e9-a9cd-6045cb34583b');
print(id.toString()); // c860fcd8-19ec-11e9-a9cd-6045cb34583b
print(id.format(braces: true, dashes: false)); // {c860fcd819ec11e9a9cd6045cb34583b}
copied to clipboard
The toString() of a Uuid object simply calls format(dashes: true, braces: false) which gives a string in the canonical format
Byte Conversion #
From bytes to Uuid
var id = Uuid.fromBytes([32, 151, 65, 3, 195, 188, 70, 18, 164, 78, 243, 206, 153, 208, 36, 86]);

print(id); // 20974103-c3bc-4612-a44e-f3ce99d02456
print(id.version); // 4
print(id.variant); //UuidVariant.rfc4122
copied to clipboard
An optional parameter offset can be passed to Uuid.fromBytes in order to skip a number of bytes in the list before beginning parsing the bytes
var id = Uuid.fromBytes([0xff, 0xff, 32, 151, 65, 3, 195, 188, 70, 18, 164, 78, 243, 206, 153, 208, 36, 86], offset: 2);
copied to clipboard
Map and Set #
Uuid objects can be used in Set and Map keys
var same1 = Uuid.fromBytes([195, 68, 112, 225, 75, 32, 73, 209, 145, 97, 172, 87, 233, 64, 202, 233]);
var same2 = Uuid.fromBytes([195, 68, 112, 225, 75, 32, 73, 209, 145, 97, 172, 87, 233, 64, 202, 233]);
var diff = Uuid.v4();

var map = <Uuid, String>{}; // map with Uuid as key
map[same1] = 'Awesome sauce';
map[diff] = 'Sour grapes';

// a different Uuid object, but the same value
print(map[same2]); // Awesome sauce
copied to clipboard
More detailed examples are in the test folder