Skip to main content

Linkdrops

Linkdrops allow users to distribute assets and onboard people to Web3 apps through a simple web link.

Linkdrop

They work by storing assets and linking AccessKeys to them. The AccessKeys are then distributed to users in the form of web links. These links take users to a website that automatically uses the keys to call the claim method in the linkdrop contract.

In order for a contract to be considered a Linkdrop-contract it has to follow the NEP-452 standard. The NEP-452 explains the minimum interface required to be implemented, as well as the expected functionality.


Keypom

The simplest way to create Linkdrops is by using Keypom. Keypom is a community project that allows you to create Linkdrops for NEAR tokens and NFTs in a few clicks.

keypom


AccessKeys

In order to create any kind of drop, you need to first generate key pairs. You will need to create one key per drop.

  • The linkdrop contract will store the public part of the key.
  • You will give the private part of the key to the user you want to receive the drop.
const dropsNumber = "2";
const keysGeneratorUrl = "https://keypom.sctuts.com/keypair/";
const rootEntrophy = "my-password"; //If not provided, the keypair will be completely random. see: https://docs.keypom.xyz/docs/next/keypom-sdk/Core/modules
asyncFetch(keysGeneratorUrl + dropsNumber + "/" + rootEntrophy).then((res) => {
const keyPairs = JSON.parse(res.body);
const pubKeys = [];
const privKeys = [];

keyPairs.forEach((e) => {
pubKeys.push(e.pub);
privKeys.push(e.priv);
});

const obj = {
publicKeys: pubKeys,
privKeys: privKeys,
};

State.update(obj);
});

$NEAR Drops

To create a $NEAR drop you will ask the contract to create a drop (create_drop), passing the public part of the keys you generated, and how much you want to drop on each key use (deposit_per_use).

The contract will create a drop and return the numerical ID that identifies it.

const keypomContract = "v2.keypom.near";
const dropAmount = "10000000000000000000000";

Near.call([
{
contractName: keypomContract,
methodName: "create_drop",
args: {
public_keys: state.publicKeys,
deposit_per_use: dropAmount,
},
deposit: "23000000000000000000000", // state.publicKeys.length * dropAmount + 3000000000000000000000,
gas: "100000000000000",
},
]);
info

To claim the drop, you will need to send the user a link with the private key


NFT Drops

To drop an existing NFT, you will (1) create a drop, and then (2) transfer the NFT to keypom.

1. Creating the Drop

To create an NFT drop, you will call the create_drop method, now passing a nft argument, which will tell the linkdrop contract to wait for an NFT to be transferred.

The contract will then create a drop and return the numerical ID that identifies it.

const accountId = context.accountId ?? props.accountId;
const keypomContract = "v2.keypom.near";
const nftContract = "nft.primitives.near";
const dropAmount = "10000000000000000000000";

Near.call([
{
contractName: keypomContract,
methodName: "create_drop",
args: {
public_keys: state.publicKeys,
deposit_per_use: dropAmount,
nft: {
// Who will be sending the NFTs to the Keypom contract
sender_id: accountId,
// NFT Contract Id that the tokens will come from
contract_id: nftContract,
},
},
deposit: "23000000000000000000000" // state.publicKeys.length * dropAmount + 3000000000000000000000,
gas: "100000000000000",
},
]);

2. Transferring the NFT

Having the Drop ID, you now need to transfer the NFT to the linkdrop contract, specifying to which drop you want to add it.

const nftTokenId = "1";

Near.call([{
contractName: nftContract,
methodName: 'nft_transfer_call',
args: {
receiver_id: keypomContract,
token_id: nftTokenId,
msg: dropId.toString()
},
deposit: "1",
gas: "300000000000000"
}]);
tip

The linkdrop contract will validate that you are transferring the NFT to a drop that belongs to you


FT Drops

The process to drop a Fungible Token is very similar to that of creating an NFT drop. You will first create the drop, and then fund it with FTs.

1.Creating a drop

To create a FT drop you will call the create_drop method, now passing a ftData argument, which will tell the linkdrop contract to wait for a certain amount of FT to be transferred.

The contract will then create a drop and return the numerical ID that identifies it.

const keypomContract = "v2.keypom.near";
const ftContract = "ft.primitives.near";
const dropAmount = "10000000000000000000000";

Near.call([
{
contractName: keypomContract,
methodName: "create_drop",
args: {
public_keys: state.publicKeys,
deposit_per_use: dropAmount,
ftData: {
contractId: ftContract,
senderId: accountId,
// This balance per use is balance of human readable FTs per use.
amount: "1"
// Alternatively, you could use absoluteAmount, which is dependant on the decimals value of the FT
// ex. if decimals of an ft = 8, then 1 FT token would be absoluteAmount = 100000000
},
},
deposit: "23000000000000000000000", // state.publicKeys.length * dropAmount + 3000000000000000000000,
gas: "100000000000000"
},
]);

2. Transferring FT

Having the Drop ID, you now need to transfer the fungible tokens to the linkdrop contract.

note

To transfer FTs to an account, you need to first register the receiver account (e.g. the keypom contract) on the FT contract.

Near.call([
{
contractName: ftContract,
methodName: "ft_transfer",
args: {
receiver_id: keypomContract,
amount: "1",
},
deposit: "1",
gas: "300000000000000",
},
]);

Function Call Drop

Linkdrop contracts allow to create function call drops. These drops will execute one or more methods on a contract when the user claims the drop.

tip

Function call drops can be thought as the abstract version of other drops: you can create a drop that will mint an NFT, register a user in a DAO, or pay for a service.

const accountId = context.accountId ?? props.accountId;
const keypomContract = "v2.keypom.near";
const nftContract = "nft.primitives.near";
const nftTokenId = "1";
const dropAmount = "10000000000000000000000";

Near.call([
{
contractName: keypomContract,
methodName: "create_drop",
args: {
public_keys: state.publicKeys,
deposit_per_use: dropAmount,
fcData: {
// 2D array of function calls. In this case, there is 1 function call to make for a key use
// By default, if only one array of methods is present, this array of function calls will be used for all key uses
methods: [
// Array of functions for Key use 1.
[{
receiverId: nftContract,
methodName: "nft_mint",
args: JSON.stringify({
// Change this token_id if it already exists -> check explorer transaction
token_id: nftTokenId,
metadata: {
title: "My NFT drop",
description: "",
media: "",
}
}),
accountIdField: "receiver_id",
// Attached deposit for when the receiver makes this function call
attachedDeposit: "10000000000000000000000"
}]
]
}
},
deposit: "23000000000000000000000", // state.publicKeys.length * dropAmount + 3000000000000000000000,
gas: "100000000000000",
},
]);

const getLinks = () => {
const links = [];

// It assumes that private keys have been already stored in State by using State.init() and State.update() method
state.privKeys.map((e, i) => {
const link =
"https://app.mynearwallet.com" + "/linkdrop/v2.keypom.near/" + e;
links.push(link);
});

return links;
};
Example response

[
'https://app.mynearwallet.com/linkdrop/v2.keypom.near/ed25519:2H32THYM8ob336yk81cZUxpidvKi34zLck6a97ypmCY8bbSAuEfrCTu9LWmWGiG9df2C6vkg2FGKGZzY9qE4aEcj',
'https://app.mynearwallet.com/linkdrop/v2.keypom.near/ed25519:3eoMcqKmmY9Q6qgBy3hZy65HisZ8NXQd9aGGYUGe6RRsmNpGJS5YN64MgZaBVVYJJhbFXhQ2ca3DRRBiKh1rYM48'
]

note

If you didn't save your linkdrop links before closing NEAR App, you can always find them on Keypom app.


Additional Resources

  1. Linkdrop plus allows to create a Simple Drop. Powered by Keypom
  2. Keypom Drop Viewer shows drops created by current logged in user.
Was this page helpful?