What are Kalao metadata standards
Kalao respects ERC721 standard which is a free and open standard that describes how to build non-fungible or unique tokens on blockchain. It requires that your smartcontract return a URI where Kalao can find the metadata. To do so, we use the tokenURI function. The contract should return an HTTPS or IPFS URL and this URL should in turn return a JSON blob of data with the metadata for your token.
Finally, metadata allows these assets to have additional properties, such as a name, description, and image.
Metadata structure
Kalao supports metadata that is structured according to the official ERC721 metadata standard such as:
Kalao marketplace supports different kind of properties including image, audio, video… You can check the following table to see how properties works:
Image
This is the URL to the image of the item. Can be just about any type of image, and can be IPFS URLs or paths. We recommend using a 500 x 500 image.
It’s also the URL used to add an image or an audio for your cover.
External data
This is the URL that will appear below the asset's image on Kalao and will allow users to leave Kalao and view the item on your site.
Description
A description of the NFT.
Name
Name of the NFT.
Attributes
These are the attributes for the NFT, which will show up on the Kalao NFT page.
Animation URL
The file extensions for a video supported: MP4, M4V or WEBM. Max 30mb.
The file extensions for a music supported: MP3 or WAV. Max 30mb.
Metadata example
When creating an NFT on the Kalao marketplace, you will add a name, a description, properties
When the NFT is created and for sale, you will be able to see metadata.
And these metadata will be written like below in the code:
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