Collections

Collections

A "Collection" in the context of Phosphor is a unique grouping of items linked or deployed to a smart contract on a network supported by Phosphor. This collection adheres to a specific token standard, either ERC721 or ERC1155. Each item within the collection is assigned a unique token ID based on a predetermined strategy. The functionalities of a collection can vary depending on the type of contract deployed.

A Collection has following characteristics:

• It groups together a set of items.
• It can be deployed or linked to a smart contract on a network supported by Phosphor.
• It implements a specific token standard, being either ERC721 or ERC1155.
• It has a token ID assignment strategy, which determines how the items within the collection receive their token IDs.
• It enables different functionalities based on the contract your deploy.

Token ID Assignment Strategy

Token ID Assignment Strategy	Contract Support	Item Locking	Contract Mint function
AUTOMATIC	ERC721, ERC1155	Automatically assigns a token ID when locking an Item.	Expects a token ID when calling the mint function. A token with the ID is minted from the contract.
MANUAL	ERC721, ERC1155	Requires manually passing a token ID when locking an Item.	Expects a token ID when calling the mint function. A token with the ID is minted from the contract.
EXTERNAL	ERC721	No token ID required when locking an Item.	Expects no token ID when calling the mint function. Token ID will be assigned during the mint function.

Contract setup

The following table lists the different ways to configure the smart contract for a collection.

Contract type	Description
Platform	The platform provides a few default contracts that a user can choose from, including FrozenERC721, FrozenERC1155, FlexibleERC721, FlexibleERC1155, and SignatureERC721. See more on using platform contracts.
Custom	The user provides a custom smart contract implementation subject to restrictions below. This is also referred to in our documentation as Bring Your Own Contract (BYOC).
External	The user links the collection to an existing smart contract on a network supported by Phosphor.

Learn how to configure collection contracts.

tip

When using platform contracts, one can take advantage of a few embedded characteristics our template contracts offer, such as:

• Full ownership: A user can specify the wallet that should be the owner of this contract. Contract owners can perform all functions defined by the contract and grant or revoke admin roles (the Phosphor platform, in this instance, is given an admin role).

• Define Items as non-transferable or “soulbound”: A soulbound contract does not allow item owners to transfer their items. It disables all resale activities and marks the items' permanent ownership.

• Editable metadata: Contracts with this characteristic enable the owner to change the metadata after the item is minted.

Restrictions

To ensure that a custom contract is compatible with the platform, the deployment process will check for specific capabilities.

To determine the token type of the contract, the contract must have one of the following capabilities:

• ERC721
• ERC1155

To mint NFTs through the platform, the contract must have one of the following capabilities:

• ADMIN_MINT_SINGLE
• ADMIN_MINT_SINGLE_URI
• ADMIN_MINT_MULTIPLE
• ADMIN_MINT_MULTIPLE_NO_ID
• MINT_VOUCHER

Capabilities

The Capability abstraction is used throughout the Phosphor platform. A capability is an array of JSON objects containing the signatures of the related smart contract members (functions, events, etc.). A capability is associated with an Application Binary Interface (ABI).

Each time the platform interacts with a smart contract, it ensures that it has the required capabilities. This generic approach makes the platform compatible with a variety of smart contracts, even allowing users to bring their own custom contracts into the platform.

You can get the known capabilities ABIs from the public capabilities endpoint.

Feature Mapping

The following table lists the most common capabilities and their equivalent platform features.

Note that not all capabilities are listed here, this is just a sample.

Capability	Feature
ERC 721, ERC 1155	Collection contract deployment and item ownership transfer.
CONTRACT_ROYALTY, PER_TOKEN_ROYALTY	Item and collection royalty management.
ADMIN_MINT_SINGLE, ADMIN_MINT_SINGLE_URI, ADMIN_MINT_SINGLE_URI	Functions to mint a single NFT per transaction.
MINT_VOUCHER	The function that mints NFTs based on the quantity of a voucher.
ADMIN_MINT_MULTIPLE	The function that mints multiple NFTs in one transaction.