Whenever an `Announcement` is parsed as transparent transaction info, we obtain
information about the UTXOs involved in that transaction. It would be nice to
display this information when we look up the UTXO, but there is no way to query
it from neptune-core.
This commit caches that information in order to display it.
Specifically, it extends `AppState` with a (smart pointer to) vector of
`TransparentUtxoInfo` (a new type). The vector, or its existing entries, are
extended with new information when it becomes available.
At this point the vector is rather silly because it is not persisted, and the
app reboots more often than not, resulting in a clear cache. A future commit
will persist this data.
Every transaction can have zero or more announcements, which are essentially
messages that must be included across all future mergers and updates.
Announcements are typically used for transmitting information related to
receiving UTXOs, encrypted. However, a new use case is that of *transparent
transaction info*, which is an announcement containing the UTXOs and the
commitment randomnesses needed to reproduce the transaction's inputs and
outputs. With such a transparent transaction info announcement, third parties
can transparently audit transactions.
This commit adds a page for viewing announcements, and if the announcement can
be parsed as a transparent transaction info type announcement then it is
rendered as such, complete with native currency amounts and linkable UTXOs
(where possible).
The path for accessing announcements is any of
- `/announcement/digest/<hex-string>/<index>`
- `/announcement/tip/<index>`
- `/announcement/genesis/<index>`
- `/announcement/height/<height>/<index>`
- `/announcement/height_or_digest/<height-or-diges>/index/<index>`.
The last bullet point exists to support the quick lookup functionality, which is
also new. A `AnnouncementSelector` has display and from-string methods relating
these path formats to the relevant object. A suite of (prop)tests verifies
parsing.
Also, this commit enables mocking, which is useful when the neptune-core node
the explorer is connected to is outdated, unsynced, or for whatever reason does
not serve the desired data. The RPC client call is intercepted, and if it fails
and mocking is enabled, an imagined (pseudorandom) resource of the requested
type is returned. To enable mocking, compile with the "mock" feature flag and
set the "MOCK" environment variable.
