matrix-doc/api/server-server/examples/pdu.json

{
    "$ref": "unsigned_pdu.json",
    "hashes": {
        "sha256": "thishashcoversallfieldsincasethisisredacted"
    },
    "signatures": {
        "example.com": {
            "ed25519:key_version:": "these86bytesofbase64signaturecoveressentialfieldsincludinghashessocancheckredactedpdus"
        }
    }
}