hub

Simplified, read-only view types over gno.land/p/gnoland/boards data: Board, Thread, Comment, Flag and Member.

Realms use these to expose board contents through a query API without handing callers access to their own persistent state.

Invariant

A safe type is a snapshot, never a live reference.

Each NewSafe* constructor reads the fields it needs off the boards value and copies them. It keeps no pointer to the source, so a value returned to a caller cannot be used to reach — let alone mutate — the realm data it was built from. Counts (ThreadCount, FlagCount, …) are resolved at construction time and do not track later changes.

Keep it that way when adding fields:

• Copy scalars. Never store the *boards.Board / *boards.Post the constructor was handed, and never expose a boards.PostStorage, boards.FlagStorage or boards.Permissions — those are handles onto live realm state.
• Deep-copy slices and maps, as NewSafeBoard does for Aliases and NewSafeMember does for Roles. Copy on the way out too: a getter that returns the stored slice lets a caller mutate the snapshot and change what the same value reports on the next call, so Aliases() and Roles() each return a fresh slice.
• Convert boards types to plain ones where practical, the way Member flattens []boards.Role to []string.

An earlier version of these types carried a ref field plus Iterate* methods that walked realm storage through it. That is the thing this package exists to not do.

Usage

 1import (
 2    "gno.land/p/gnoland/boards"
 3    hubexts "gno.land/p/gnoland/boards/exts/hub"
 4)
 5
 6func GetBoard(id uint64) (hubexts.Board, bool) {
 7    b, found := gBoards.Get(boards.ID(id))
 8    if !found {
 9        return hubexts.Board{}, false
10    }
11    return hubexts.NewSafeBoard(b), true
12}

The constructors panic on a nil reference, and on a post whose kind does not match (NewSafeThread on a comment, or NewSafeComment on a thread). Resolve and check existence before calling them.