Non-Fungible Tokens (NFTs)

These NFTs are unique, one-of-a-kind tokens that are built on blockchain technology, allowing for secure ownership and transfer of these assets. Every token is assigned a unique identification code(ticker) and metadata that distinguishes it from every other token.

The flow of issuing and transferring non-fungible tokens is:

register/issue the token (this step creates an empty collection);
set roles to the address that will create the NFT/SFTs;
create the NFT/SFT;
transfer quantity(es).

Issuance of NFT tokens

One has to perform an issuance transaction in order to register a non-fungible token. Non-Fungible Tokens are issued via a request to the Metachain, which is a transaction submitted by the Account which will manage the tokens. When issuing a token, one must provide a token name, a ticker and optionally additional properties. This transaction has the form:

IssuanceTransaction {
    Sender: <account address of the token manager>
    Receiver: erd1qqqqqqqqqqqqqqqpqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqzllls8a5w6u
    Value: 50000000000000000 # (0.05 EGLD)
    GasLimit: 60000000
    Data: "issueNonFungible" +
          "@" + <token name in hexadecimal encoding> +
          "@" + <token ticker in hexadecimal encoding>
}

Optionally, the properties can be set when issuing a token. Example:

IssuanceTransaction {
    Sender: <account address of the token manager>
    Receiver: erd1qqqqqqqqqqqqqqqpqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqzllls8a5w6u
    Value: 50000000000000000 # (0.05 EGLD)
    GasLimit: 60000000
    Data: "issueNonFungible" +
          "@" + <token name in hexadecimal encoding> +
          "@" + <token ticker in hexadecimal encoding> +
          "@" + <"canFreeze" hexadecimal encoded> + "@" + <"true" or "false" hexadecimal encoded> +
          "@" + <"canWipe" hexadecimal encoded> + "@" + <"true" or "false" hexadecimal encoded> +
          "@" + <"canPause" hexadecimal encoded> + "@" + <"true" or "false" hexadecimal encoded> +
          "@" + <"canTransferNFTCreateRole" hexadecimal encoded> + "@" + <"true" or "false" hexadecimal encoded> +
          "@" + <"canChangeOwner" hexadecimal encoded> + "@" + <"true" or "false" hexadecimal encoded> +
          "@" + <"canUpgrade" hexadecimal encoded> + "@" + <"true" or "false" hexadecimal encoded> +
          "@" + <"canAddSpecialRoles" hexadecimal encoded> + "@" + <"true" or "false" hexadecimal encoded> +
          ...
}

Practice

Let's create our first NFT collection. We will make a transaction to the testnet blockchain via mxpy tool. To install the tool check the prerequisites section.

costin@Byblos:~$ mxpy contract call erd1qqqqqqqqqqqqqqqpqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqzllls8a5w6u --pem ~/multiversX/keys/shard0.pem --proxy https://testnet-api.multiversx.com --chain T --recall-nonce --gas-limit 60000000 --value 50000000000000000 --function issueNonFungible --arguments 0x425044414578616d706c65546f6b656e 0x42504441  --send

We called that specific contract, signed with my pem to authenticate myself in the blockchain, used testnet proxy and chain, sent 0.05 EGLD, called issueNonFungible, using 2 parameters:

0x425044414578616d706c65546f6b656e which is the name - BPDAExampleToken in hex;
0x42504441 which is the ticker - BPDA in hex.

Let's check our NFT collection on blockchain: BPDA_NFT

Observe that the Collection Name (which is also known as token ID) is BPDA-2d3d3c. This is formed using the ticker provided,"-" and 6 random hex numbers. Also, observe the name BPDAExampleToken which is the one we provided. Lastly, observe that we have an empty collection, with no NFTs.

Practice - your turn

Create an NFT collection.

Assigning roles to an NFT Collection

Roles can be assigned by sending a transaction to the Metachain from the ESDT manager. Within a transaction of this kind, any number of roles can be assigned (minimum 1).

RolesAssigningTransaction {
    Sender: <address of the ESDT manager>
    Receiver: erd1qqqqqqqqqqqqqqqpqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqzllls8a5w6u
    Value: 0
    GasLimit: 60000000
    Data: "setSpecialRole" +
          "@" + <token identifier in hexadecimal encoding> +
          "@" + <address to assign the role(s) in a hexadecimal encoding> +
          "@" + <role in hexadecimal encoding> +
          "@" + <role in hexadecimal encoding> +
          ...
}

Don't forget to convert the values to hex. For example, ESDTRoleNFTCreate = 0x45534454526f6c654e4654437265617465.

NFT fields

Below you can find the fields involved when creating an NFT:

NFT Name
- The name of the NFT or SFT;
Quantity
- The quantity of the token. If NFT, it must be 1;
- There are Semi-Fungible Tokens (SFT). You can read more here;
Royalties - Allows the creator to receive royalties for any transaction involving their NFT
- Allows the creator to receive royalties for any transaction involving their NFT;
- Base format is a numeric value between 0 an 10000 (0 meaning 0% and 10000 meaning 100%)
Hash
- Arbitrary field that should contain the hash of the NFT metadata;
- Optional filed, should be left null when building the transaction to create the NFT;
Attributes
- Represents additional information about the NFT or SFT, like picture traits or tags for your NFT/collection;
- The field should follow a metadata:ipfsCID/fileName.json;tags:tag1,tag2,tag3 format;
- Below you can find a sample for the extra metadata format that should be stored on IPFS:

{
  "description": "This is a sample description",
  "attributes": [
    {
      "trait_type": "Background",
      "value": "Yellow",
      "{key}": "{value}",
      "{...}": "{...}",
      "{key}": "{value}"
    },
    {
      "trait_type": "Headwear",
      "value": "BlackBeanie"
    },
    {
      "trait_type": "SampleTrait3",
      "value": "SampleValue3"
    }
  ],
  "collection": "ipfsCID/fileName.json"
}

URI(s)
- Mandatory field that represents the URL to a supported media file ending with the file extension as described in the example below;
- Field should contain the Uniform Resource Identifier;

NOTE

Please note that each argument must be encoded in hexadecimal format with an even number of characters.

Creation of an NFT

A single address can own the role of creating an NFT for an ESDT token. This role can be transferred by using the ESDTNFTCreateRoleTransfer function.

An NFT can be created on top of an existing ESDT by sending a transaction to self that contains the function call that triggers the creation. Any number of URIs can be assigned (minimum 1).

NFTCreationTransaction {
    Sender: <address with ESDTRoleNFTCreate role>
    Receiver: <same as sender>
    Value: 0
    GasLimit: 3000000 + Additional gas (see below)
    Data: "ESDTNFTCreate" +
          "@" + <token identifier in hexadecimal encoding> +
          "@" + <initial quantity in hexadecimal encoding> +
          "@" + <NFT name in hexadecimal encoding> +
          "@" + <Royalties in hexadecimal encoding> +
          "@" + <Hash in hexadecimal encoding> +
          "@" + <Attributes in hexadecimal encoding> +
          "@" + <URI in hexadecimal encoding> +
          "@" + <URI in hexadecimal encoding> +
          ...
}

Additional gas refers to:

Transaction payload cost: Data field length * 1500 (GasPerDataByte = 1500);
Storage cost: Size of NFT data * 50000 (StorePerByte = 50000).

Transfer NFT Creation Role

The role of creating an NFT can be transferred by a Transaction like this:

TransferCreationRoleTransaction {
    Sender: <address of the current creation role owner>
    Receiver: erd1qqqqqqqqqqqqqqqpqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqzllls8a5w6u
    Value: 0
    GasLimit: 60000000 + length of Data field in bytes * 1500
    Data: "transferNFTCreateRole" +
          "@" + <token identifier in hexadecimal encoding> +
          "@" + <the address to transfer the role from in hexadecimal encoding> +
          "@" + <the address to transfer the role to in hexadecimal encoding>
}

Change NFT Attributes

An user that has the `ESDTRoleNFTUpdateAttributes`` role set for a given ESDT, can change the attributes of a given NFT/SFT.

NOTE

ESDTNFTUpdateAttributes will remove the old attributes and add the new ones. Therefore, if you want to keep the old attributes you will have to pass them along with the new ones.

This is done by performing a transaction like this:

ESDTNFTUpdateAttributesTransaction {
    Sender: <address of an address that has ESDTRoleNFTUpdateAttributes role>
    Receiver: <same as sender>
    Value: 0
    GasLimit: 10000000
    Data: "ESDTNFTUpdateAttributes" +
          "@" + <token identifier in hexadecimal encoding> +
          "@" + <NFT or SFT nonce in hexadecimal encoding> +
          "@" + <Attributes in hexadecimal encoding>
}

Transfers

Performing an ESDT NFT transfer is done by specifying the receiver's address inside the Data field, alongside other details. An ESDT NFT transfer transaction has the following form:

TransferTransaction {
    Sender: <account address of the sender>
    Receiver: <same as sender>
    Value: 0
    GasLimit: 1000000 + length of Data field in bytes * 1500
    Data: "ESDTNFTTransfer" +
          "@" + <collection identifier in hexadecimal encoding> +
          "@" + <the NFT nonce in hexadecimal encoding> +
          "@" + <quantity to transfer in hexadecimal encoding> +
          "@" + <destination address in hexadecimal encoding>
}

Branding

Here is SubcarpatiOGs NFT Collection. Stramosi NFT

Observe that there are Social links, a Description and you can even see a Logo.

For branding you NFT collection please read the instructions.

Non-Fungible Tokens (NFTs)

Issuance of NFT tokens​

Practice​

Practice - your turn​

Assigning roles to an NFT Collection​

NFT fields​

Creation of an NFT​

Transfer NFT Creation Role​

Change NFT Attributes​

Transfers​

Branding​