Recommended canonical string encoding for EndpointId / PublicKey

[2color]

I have a question about the recommended string encoding for EndpointIds

The context is radicle-artifact which augments radicle with signed content-addressed artifact distribution. From a technical perspective, radicle-artifact is modelled as a CRDT whose actions are stored as JSON in git storage. Given this, I want to strike the right balance between efficiency, interoperability, and pragmatism.

From iroh-base/src/key.rs, EndpointId is just a type alias for PublicKey, and the current string behaviour seems a bit mixed:

• Display for PublicKey renders as lowercase hex
• human-readable serde also uses to_string(), so when serialising as JSON the endpoint is hex
• FromStr for PublicKey accepts {hex, but also accepts base32 via decode_base32_hex
• there are also explicit to_z32() / from_z32() helpers for z-base-32

That left me unsure what the recommended canonical textual form of an endpoint ID is supposed to be.

A few specific questions:

1. Assuming string based storage, i.e. JSON, the base32/z-base-32 are clearly more efficient than hex, but it's not clear which is recommended between the two. Assuming DNS based discovery, I suppose there's convenience to be gained from being able to use pkarr tooling but I'm not familiar with all the trade-offs here.

2. Is hex considered the canonical/default representation, with base32 formats supported only as parsing conveniences? (this comment from @dignifiedquire seems to support this, though it's not clear what the referenced drawbacks of different alphabets, like base3, are)

Thanks

[matheus23]

The recommended canonical textual form of an endpoint ID is generally lowercase hex-encoding, but think of it similar to the canonical encoding of sha2sum/sha3sum, b3sum or whateversum is hex as well.

base32 encoding exists for backwards compatibility reasons: We switched from base32 to hex in the past.

z32 encoding exists for use with Pkarr, which uses z32, but that's supposed to be only used for z32.