HIP-20: Standardized URI scheme to reference Hedera data
| Author | Khoa Luong, Sam Wood, Stephanie Yi, Declan Fox |
|---|---|
| Discussions-To | https://github.com/hashgraph/hedera-improvement-proposal/discussions/110 |
| Status | Replaced ⓘ |
| Needs Council Approval | Yes ⓘ |
| Type | Standards Track ⓘ |
| Category | Service ⓘ |
| Created | 2021-06-29 |
| Superseded by | 30 |
Table of Contents
Abstract
This HIP defines a way for Hedera to host data in a centralized location and accessible with a standardized URI.
Motivation
Non-fungible tokens often have metadata associated with them and this HIP provides a way to access them with a standardized URI, hosted by Hedera. Third-party applications would then be able to use this standardized URI to integrate with and display a token’s metadata and image (for example: DECENT Wallet [0]). Non-Hedera NFT’s could also utilize this feature to host their metadata, like ERC-721.
Rationale
The format of the URI includes the prefix “hcs” to represent that it is hosted on Hedera, and then the network that the token was deployed on (mainnet/testnet), followed by the topic ID. Currently, Hedera’s ID convention can be confusing because a topic ID on one network can be a wallet ID in another network, so by using this prefix, we can start standardizing the format of the IDs. For example, using HCS to distinguish data hosted on Hedera consensus service, HFS prefix for Hedera file service, as well as including the associated network (testnet, previewnet).
One use case for the topic ID to be part of the URI is: the metadata of an NFT can be submitted to this topic as a message and then retrieved by accessing this standardized URI. This gives us an easy way to send the token’s metadata to Hedera without the need for a new API. The token’s metadata URI would then be stored on the memo field of the token when it is deployed.
Specification
Different Hedera services have different prefixes, for example, HFS for Hedera file service and
HCS for Hedera consensus service.
The URI is in the following format: hcs-
Backwards Compatibility
This feature is optional for deployed Hedera tokens so there won’t be any backward compatibility concerns.
Security Implications
No known security concerns.
How to Teach This
Reference Implementation
Rejected Ideas
Open Issues
References
[0] https://dcentwallet.com/features/erc721-wallet [1] https://github.com/hashgraph/hedera-improvement-proposal/blob/master/HIP/hip-10.md
Copyright/license
This document is licensed under the Apache License, Version 2.0 – see LICENSE or (https://www.apache.org/licenses/LICENSE-2.0)
Citation
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