Collections

Intro

NFTs have become much easier to issue, and we're seeing increasing amounts minted daily, mainly through NFT collections. This article will dive into NFT collection minting and some popular examples of how to work with NFT collections in Unique Network.

As the name implies, an NFT collection is a unique collection of NFTs. NFT artworks are generally created on a smaller scale with the involvement of concerned content creators or digital artists. In addition, you would also notice that individual NFT artworks are available for sale on different NFT marketplaces.

In Unique Network, the collection has the following entities:

name - a collection name that defines it in the global scope;
description - some additional details about the collection;
token prefix - short string value that will be added to token IDs.
properties - a unique set of keys and values which defines collection specifics;
limits - a set that defines the rules for a collection, e.g., whether it can be transferred or how many tokens you can mint in it;
owner - an address that created a collection (or if the collection was transferred, the address that owns the collection at the moment);
admins - a collection can be controlled by multiple admin addresses. Admins can issue and burn NFTs, as well as add and remove other admins, but they cannot change NFT or collection ownership;

Prerequisite

Follow the Getting started guide to install required libraries, receive test network OPL tokens, and initialize SDK.

Creating a collection

Below is an (almost) minimum example. Only collection name, description, and symbol are mandatory fields. They exist at the collection level and cannot be overridden.

Collection coverage is a part of collection metadata and is not a mandatory field.

const collectionTx = await sdk.collection.create({
 name: "Test",
 description: "Test collection",
 symbol: "TST",
 info: {cover_image: {url: 'https://gateway.pinata.cloud/ipfs/QmTkhTg5S5zrqJL3UsKtyiFi8fcMT3Cao9uKtadp3Ckh7m'}},
});

console.log("Collection ID:", collectionTx.result.collectionId);

In Unique Network every collection has a unique collection ID. You will need it later to mint NFTs.

You can check your collection successfully created on Unique Scanopen in new window.

Collection modes

There are three different collection modes in Unique Network:

NFT (default)
Fungible
ReFungible

You can specify the mode of collection during minting.

await sdk.collection.create({
 name: "Test",
 description: "Test collection",
 symbol: "TST",
 info: {cover_image: {url: coverImage}},
 mode: 'Fungible' // <--- set collection mode here 
});

Collection properties

Every collection in Unique Network can have up to 64 properties—a unique set of keys and values that define collection specifics. Some of them relate to NFT metadata and are set automatically by SDK.

Setting collection properties

During the collection creation, you can set collection limits as follows:

const {result} = await sdk.collection.create({
  name: "Test",
  description: "Test collection",
  symbol: "TST",
  info: {cover_image: {url: "https://gateway.pinata.cloud/ipfs/QmTkhTg5S5zrqJL3UsKtyiFi8fcMT3Cao9uKtadp3Ckh7m"}},
  properties: [ //  <--- set collection properties here 
  {key: "A", value: "value A"},
  {key: "B", value: "value B"},
  ]
});

Later you can set new properties or modify previously created ones.

...

await sdk.collection.setProperties({
  collectionId: result.collectionId,
  properties: [{key: "C", value: "value C"}]
});

Now, let's query our collection and check its properties

const collection = await sdk.collection.get({collectionId: result.collectionId});

console.log(collection.properties);

The result will be as follows, let's break it down.

[
  {
    key: "A",
    value: "value A",
    valueHex: "0x76616c75652041",
  },
  {
    key: "B",
    value: "value B",
    valueHex: "0x76616c75652042",
  },
  {
    key: "C",
    value: "value C",
    valueHex: "0x76616c75652043",
  },
  {
    key: "collectionInfo",
    value: "{\"schemaName\":\"unique\",\"schemaVersion\":\"2.0.0\",\"cover_image\":{\"url\":\"https://gateway.pinata.cloud/ipfs/QmTkhTg5S5zrqJL3UsKtyiFi8fcMT3Cao9uKtadp3Ckh7m\"}}",
    valueHex: "0x7b22736368656d614e616d65223a22756e69717565222c22736368656d6156657273696f6e223a22322e302e30222c22636f7665725f696d616765223a7b2275726c223a2268747470733a2f2f676174657761792e70696e6174612e636c6f75642f697066732f516d546b6854673553357a72714a4c3355734b74796946693866634d543343616f39754b7461647033436b68376d227d7d",
  },
  {
    key: "schemaName",
    value: "unique",
    valueHex: "0x756e69717565",
  },
  {
    key: "schemaVersion",
    value: "2.0.0",
    valueHex: "0x322e302e30",
  },
]

Properties A, B, and C has been manually set during the collection creation and modifying collection with setCollectionLimits
The SDK sets' properties schemaName, schemaVersion, and collectionInfo and relate to the Unique metadata. You can read more about Unique Schema in the reference section.

Token property permissions

Every NFT token inside the collection can have properties. The list of allowed properties and their mutability permissions are handled on the collection level.

Let's look at how to specify them.

await sdk.collection.create({
  name: "Test",
  description: "Test collection",
  symbol: "TST",
  info: {cover_image: {url: coverImage}},
  tokenPropertyPermissions: [ // <--- set token property permissions here 
    {key: 'A', permission: {mutable: true, collectionAdmin: true, tokenOwner: true}},
    {key: 'B', permission: {mutable: false, collectionAdmin: false, tokenOwner: false}},
    {key: 'C', permission: {mutable: false, collectionAdmin: false, tokenOwner: true}},
  ]
});

Every NFT token in the collection above could have three properties:

A: this property is mutable; it could be set during the NFT minting. Later, it could be rewritten by the collection admin or NFT owner
B: this property is immutable and can be set only once during the minting
C: this property is immutable and can be set only once during the minting or later by the token owner

The SDK also specifies some additional token properties related to Unique Schema. Let's check them.

const collection = await sdk.collection.get({collectionId})

console.log(collection.tokenPropertyPermissions);

There are a lot of additional token properties, like URI, customizing_overrides, and so on. You can check more information about them in the reference section.

One of the most important token properties is tokenData, which will be a container for all token attributes. You will learn more about attributes in the NFT section.

Nesting configuration

In Unique Network, tokens can own other tokens through a mechanism known as nesting. Nesting permissions must be configured at the collection level to enable tokens within a collection to serve as parent tokens. Additionally, it is possible to limit which collections are allowed to participate in nesting and define the roles that can execute this action. Let's explore an example of how nesting can be set on a collection level.

const { result } = await sdk.collection.create({
  name: "Name",
  description: "Description",
  symbol: "SYM",
  permissions: { // <--- set nesting in the permissions section
  nesting: {
      collectionAdmin: true,
      tokenOwner: true,
      restricted: [1, 2],  // <--- restrict nesting for specific collections 
    },
  },
});

Collection limits

It is possible to set some limitations, such as:

maximum number of tokens in the collection or
how many tokens a single account can hold
whether the token can be transferred or not
and many more

You can read more about collection limits in the reference section.

And that is how you can set such limits:

await sdk.collection.create({
  name: "Test",
  description: "Test collection",
  symbol: "TST",
  limits: { // <--- set collection limits here 
    accountTokenOwnershipLimit: 1,
    ownerCanDestroy: true,
    ownerCanTransfer: false,
    sponsorApproveTimeout: 100,
    sponsoredDataRateLimit: 100,
    sponsoredDataSize: 2048,
    sponsorTransferTimeout: 10,
    tokenLimit: 300,
    transfersEnabled: false
  },
});

Sponsoring

In Unique Network, transactions with collections can be sponsored, allowing for a gasless experience where the sponsor covers the transaction fees. This enables seamless and cost-free transfers of NFTs and the execution of smart contracts, even for accounts without native tokens.

Setting sponsorship of a collection should be done in several steps.

Firstly, we need to specify an account that will pay transaction fees.

await sdk.collection.setSponsor({ collectionId, sponsor: alice.address });

Secondly, the specified account should confirm sponsorship

await sdk.collection.confirmSponsorship({ collectionId });

Finally, set sponsoring rate limits

  await sdk.collection.setLimits({
    collectionId,
    limits: {
      sponsorApproveTimeout: 0,
      sponsorTransferTimeout: 0,
    },
  });

# Collections

# Intro

# Prerequisite

# Creating a collection

# Collection modes

# Collection properties

# Setting collection properties

# Now, let's query our collection and check its properties

# Token property permissions

# Nesting configuration

# Collection limits

# Sponsoring

# Setting collection sponsor