How to prepare an entry for the registry (NA policy script)

Pre-Requisites

To register native token mappings, it is recommended to have pre-existing knowledge about Cardano native assets. Start by reading through the developer guide on Native Assets.

After creating a Cardano native asset you will need the following to proceed with the steps to generate a mapping for the registry:

• The monetary policy script for your native asset.
• The assetName associated with the monetary policy script.
• The policyId of the monetary policy script.
• The private key/s used to define your asset policy.
• Install offchain-metadata-tools (see offchain-metadata-tools).

Step 1: Generate the 'subject'

To create a new mapping, you must first obtain your metadata subject. The subject is defined as the concatenation of the base16-encoded policyId and base16-encoded name of your asset. In case your asset name is empty, then the policyId is your subject.

For this example, we will consider the following native asset:

policyId="baa836fef09cb35e180fce4b55ded152907af1e2c840ed5218776f2f" assetName="myassetname"

• Base16 encode your assetName:

$ echo -n "myassetname" | xxd -ps
6d7961737365746e616d65

• Concatenate the policyId with the base16-encoded assetName to obtain the 'subject' for your entry:

baa836fef09cb35e180fce4b55ded152907af1e2c840ed5218776f2f6d7961737365746e616d65

REMARK: With the current approach it is essential that the subject string is all lower case.

Step 2: Prepare a draft entry

• Initialise a new draft entry for the subject using token-metadata-creator

token-metadata-creator entry --init baa836fef09cb35e180fce4b55ded152907af1e2c840ed5218776f2f6d7961737365746e616d65

This creates a draft JSON file named after your subject.

Step 3: Add required fields

token-metadata-creator entry baa836fef09cb35e180fce4b55ded152907af1e2c840ed5218776f2f6d7961737365746e616d65 \
  --name "My Gaming Token" \
  --description "A currency for the Metaverse." \
  --policy policy.json

Where policy.json is the monetary policy script file that hashes to the policyId.

Step 4: Add optional fields

token-metadata-creator entry baa836fef09cb35e180fce4b55ded152907af1e2c840ed5218776f2f6d7961737365746e616d65 \
  --ticker "TKN" \
  --url "https://finalfantasy.fandom.com/wiki/Gil" \
  --logo "icon.png" \
  --decimals 4         

Step 5: Sign your metadata

Each metadata item must be signed with the key/s used to define your asset policy. For this example we assume only a single signing key is required to validate the monetary policy script and that all metadata fields will be signed at once with the signing key file. Please refer to offchain-metadata-tools for more granular options.

token-metadata-creator entry baa836fef09cb35e180fce4b55ded152907af1e2c840ed5218776f2f6d7961737365746e616d65 -a policy.skey

Step 6: Finalize your mapping

This will run some additional validations on your submission and check that it is considered valid.

token-metadata-creator entry baa836fef09cb35e180fce4b55ded152907af1e2c840ed5218776f2f6d7961737365746e616d65 --finalize

Your finalized metadata file is now ready to submit to the cardano-token-registry. Follow these steps to proceed with the submission.