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MultiAsset case study
A contextualized user journey to explore and understand the RMRK MultiAsset NFT features.
MultiAsset is a Solidity smart contract implementation by RMRK Team that allows to bind multiple assets of various types (PDF, MP3, video files etc...) to an NFT. In this journey we will explore the main features of RMRK MultiAsset.
You can explore the RMRK MultiAsset lego further, by reading the EIP that we published:
EIP-5773: Context-Dependent Multi-Asset Tokens
Ethereum Improvement Proposals
ERC-5773: Context-Dependent Multi-Asset Tokens
The case studies utilizing v2.0.0 of our package are coming soon. The current examples are of the previous version.
You can follow along using the already built case study, by cloning the following repository:
GitHub - rmrk-team/evm-multiasset-demo
GitHub
RMRK MultiAsset EVM case study
The use cases that will be explored are:
- Creation of an NFT collection that supports asset binding
- Creation of assets to addition to the NFTs of the collection
- Asset replacement
- NFT burning (with relative bound assets)
To better understand the different use cases of this standard we will transform them in situation where dynamics are clear because we are already familiar with them, but every action will be performed with smart contract functions with the help of some Typescript code.
We have 2 expert cooks, Master and his student Alice, that are travelling the world with the aim of create new innovative recipes. Both want to create a cookbook with the best exclusive contents and be remembered as great cooks in the kitchen history.
After starting their travels, Master and Alice decided to separate and they had taken two separate different paths. Master crafted his cookbook in Japan, ancient place rich with tradition and history.
// Mint cookbook (token)
await cookBookInstance.mint(
MASTER.address, // address that will receive the token
1, // amount of tokens to mint
{ value: pricePerMint } // price per token
);
During his stay Master studied a lot and after getting the inspiration he gave life to 3 raw recipes.
const INITIAL_RECIPES = 3;
console.log("Creating recipes for Master's book");
let allAddingTxs = [];
for (let i = 0; i < INITIAL_RECIPES; i++) {
allAddingTxs.push(
await cookBookInstance.addAssetEntry( // adds a new asset to the collection (not bound to any token)
`ipsf://metadata/master_recipe_${i + actual_recipe_id}`, // metadata URI of the asset
),
);
}
await Promise.all(allAddingTxs.map((addingTx) => addingTx.wait()));
The recipes were not good enough, so, after a period of perfecting and adjusting, Master added them to his cookbook.
console.log("Adding recipes to Master's book");
for (let i = 0; i < INITIAL_RECIPES; i++) {
const recipe_ID = actual_recipe_id;
actual_recipe_id++; // Update to the next ID
await cookBookInstance.addAssetToToken(
MASTER_BOOK_ID, // ID of the token that will receive the asset
recipe_ID, // ID of the asset to add
0 // ID of the asset to replace with the new one, 0 means none
); // direct addition since the adder is the owner
}
Alice also wanted to craft her cookbook, but creating recognisable recipes is not allowed to everyone, is something exclusive. So she asked Master to give her the permission to contribute to this huge project and... he said YES Adding Alice as a new contributor for the collection, so she can now insert her existing recipes to the cookbook.
💥
console.log("Adding Alice as a new collection contributor.");
await cookBookInstance.connect(MASTER).addContributor(ALICE.address);
After getting the permission, Alice crafted her book, but she did it in Argentina.
// Alice mints her cookbook
await cookBookInstance.connect(ALICE).mint(
ALICE.address, // address that will receive the token
1, // amount of tokens to mint
{ value: pricePerMint } // price per token
);
She was inspired by different tastes and she created 2 recipes adding them directly to her cookbook.
const INITIAL_ALICE_RECIPES = 2;
for (let i = 0; i < INITIAL_ALICE_RECIPES; i++) {
const recipe_ID = actual_recipe_id;
actual_recipe_id++; // Update to the next ID
await cookBookInstance
.connect(ALICE)
.addAssetEntry( // adds a new asset to the collection (not bound to any token)
`ipsf://metadata/master_recipe_${recipe_ID}` // metadata URI of the asset
);
await cookBookInstance.
connect(ALICE).
addAssetToToken(
ALICE_BOOK_ID, // ID of the token that will receive the asset
recipe_ID, // ID of the asset to add
0 // ID of the asset to replace with the new one, 0 means none
);
}
During his travel, Master created a recipe dedicated to his student and he decided to send it to Alice, to add it to her cookbook.
// Master creates a new recipe and Alice adds it to her cookbook
await cookBookInstance
.connect(MASTER)
.addAssetEntry( // adds a new asset to the collection (not bound to any token)
`ipsf://metadata/master_recipe_${actual_recipe_id}` // metadata URI of the asset
);
Alice accepted the recipe gifted from her master...
await cookBookInstance.connect(ALICE).
addAssetToToken(
ALICE_BOOK_ID, // ID of the token that will receive the asset
actual_recipe_id, // ID of the asset to add
0 // ID of the asset to replace with the new one, 0 means none
);
actual_recipe_id++; // Update to the next ID
...but she discovered that the recipe was missing something. After a long search and many attempts she found the right missing ingredient. So Alice fixed the recipe and she replaced the old one with this new, improved one.
😕
📝
// Alice creates a recipe and replaces the latest added with it
await cookBookInstance
.connect(ALICE)
.addAssetEntry( // adds a new asset to the collection (not bound to any token)
`ipsf://metadata/alice_recipe_${actual_recipe_id}` // metadata URI of the asset
);
const WRONG_RECIPE_ID = actual_recipe_id - 1;
const FIXED_RECIPE_ID = actual_recipe_id;
console.log("Replace %d with %d", WRONG_RECIPE_ID, FIXED_RECIPE_ID);
await cookBookInstance
.connect(ALICE)
.addAssetToToken(
ALICE_BOOK_ID, // ID of the token that will receive the asset
FIXED_RECIPE_ID, // ID of the asset to add
WRONG_RECIPE_ID // ID of the asset to replace with the new one
);
actual_recipe_id++; // Update to the next ID
After this fix, Alice's career took flight and Master, proud of his student, proposed to create 2 recipes as a collaboration to add her cookbook.
// Master creates 2 recipes and add them to Alice cookbook
for (let i = 0; i < 2; i++) {
await cookBookInstance
.connect(MASTER)
.addAssetEntry( // adds a new asset to the collection (not bound to any token)
`ipsf://metadata/master_recipe_${actual_recipe_id}` // metadata URI of the asset
);
await cookBookInstance.addAssetToToken(
ALICE_BOOK_ID, // ID of the token that will receive the asset
actual_recipe_id, // ID of the asset to add
0 // ID of the asset to replace with the new one, 0 means none
);
actual_recipe_id++;
}
After a small review Alice added them to her book.
📖
// Alice accepts recipes
for (let i = 0; i < 2; i++) {
const CURRENT_recipe_ID = actual_recipe_id - 2 + i;
let acceptTx = await cookBookInstance
.connect(ALICE)
.acceptAsset( // accept pending asset
ALICE_BOOK_ID, // ID of the token that will receive the asset
0, // Index of the asset in the pending array
CURRENT_recipe_ID // ID of the asset to add
);
acceptTx.wait();
}
When the collaboration ended, Master decided to retire. He was an old man and he was also tired of travelling the world. This final decision resulted in him to burning his cookbook. His only wish was to leave a nice memory and a veil of mystery of his cooking prowess
🔥
👋
Fortunately Master's recipes will be available for the next generations, but without the permission of Alice, his loyal student, none will be able to add the recipes into future cookbooks.
await cookBookInstance.connect(MASTER).
burn(MASTER_BOOK_ID // ID of the token to burn
);
In this tutorial we have seen how to interact with the Multi-Asset implementation in order to:
- 1.Create a collection with tokens that support this standard👉
- 2.Create and add assets (resources) to a token👉
- 3.Replace an active asset with another one👉
- 4.Burn a token with all its assets bound👉
- When you add a new entry to the collection you are creating a new asset (resource) that can be used by adding it to the collection tokens, but this asset is not unique so it can be added to multiple different tokens.
- In this implementation, the assets cannot be unbound from a token. Once you add the asset with ID 5 to the token with ID 1 there is no way to remove it, so be careful when accepting new assets from unknown origins. On the other hand, an asset can be "deleted" by replacing it with a new one, this will keep the number of active assets the same.
Last modified 4mo ago