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Mint and Transfer Tokens

After deploying a token, you can mint new tokens to addresses and transfer them between wallets.

Prerequisites​

  • A deployed token (tok_...) with mintable: true
  • A wallet with the MINTER_ROLE

Minting​

Mint ERC-20 Tokens​

const tx = await urblock.transactions.mint("tok_abc123", {
  to: "0xRecipient...",
  amount: "1000000000000000000000", // 1000 tokens (18 decimals)
  idempotency_key: "mint-001",
});

Mint an ERC-721 NFT​

For ERC-721 tokens, amount is typically "1" and include a token_uri:

const tx = await urblock.transactions.mint("tok_abc123", {
  to: "0xRecipient...",
  amount: "1",
  token_uri: "ipfs://QmHash.../metadata.json",
  idempotency_key: "mint-nft-001",
});

Mint ERC-1155 Tokens​

const tx = await urblock.transactions.mint("tok_abc123", {
  to: "0xRecipient...",
  amount: "100",
  nft_token_id: 1,
  idempotency_key: "mint-1155-001",
});

Transferring​

Transfer ERC-20 Tokens​

const tx = await urblock.transactions.transfer("tok_abc123", {
  from: "0xSender...",
  to: "0xRecipient...",
  amount: "500000000000000000", // 0.5 tokens
  idempotency_key: "transfer-001",
});

Transfer an ERC-721 NFT​

const tx = await urblock.transactions.transfer("tok_abc123", {
  from: "0xSender...",
  to: "0xRecipient...",
  nft_token_id: "1",
  idempotency_key: "transfer-nft-001",
});

Transfer ERC-1155 Tokens​

const tx = await urblock.transactions.transfer("tok_abc123", {
  from: "0xSender...",
  to: "0xRecipient...",
  nft_token_id: "1",
  amount: "10",
  idempotency_key: "transfer-1155-001",
});

Burning​

Burn ERC-20 Tokens​

const tx = await urblock.transactions.burn("tok_abc123", {
  from: "0xHolder...",
  amount: "100000000000000000", // 0.1 tokens
  idempotency_key: "burn-001",
});

Burn an ERC-721 NFT​

const tx = await urblock.transactions.burn("tok_abc123", {
  from: "0xHolder...",
  nft_token_id: "1",
  idempotency_key: "burn-nft-001",
});

Approvals​

Approve a Spender (ERC-20)​

const tx = await urblock.transactions.approve("tok_abc123", {
  owner: "0xOwner...",
  spender: "0xSpender...",
  amount: "1000000000000000000",
  idempotency_key: "approve-001",
});

Transfer on Behalf (transferFrom)​

const tx = await urblock.transactions.transferFrom("tok_abc123", {
  spender: "0xSpender...",
  from: "0xOwner...",
  to: "0xRecipient...",
  amount: "500000000000000000",
  idempotency_key: "transfer-from-001",
});

Set Approval for All (ERC-721 / ERC-1155)​

const tx = await urblock.transactions.setApprovalForAll("tok_abc123", {
  owner: "0xOwner...",
  operator: "0xOperator...",
  approved: true,
  idempotency_key: "approval-all-001",
});

Important Notes​

  • All amount values are strings in the token's smallest unit (wei for 18-decimal tokens)
  • All blockchain operations are asynchronous — they return with status: "pending"
  • Use idempotency_key to prevent duplicate operations
  • NFT token IDs (nft_token_id) are numbers when minting, strings when transferring/burning

Next Steps​