Post a story to a group

Android half of ios#55, spec §6.24. An ordinary story envelope carrying
`gid`, fanned out to the members and recorded in the story set.

🔴 `Vault.groupStoryReach` returns the overlap rather than a warning: who
is excluded by this account's story audience and who is not a contact at
all, counted separately. The roster decides either way — those are two
different lists making two different statements and they will disagree —
so a disclosure that cannot name the consequence is not one.

🔴 The group label is adopted only from an actual member. The roster
check that guards group messages runs after the story branch, so without
this a sender could attach the id of a group they are not in and have
their story shown as having come from it. Dropped to null rather than
refusing the story: the story is legitimately theirs, and only the claim
about where it was posted is unverified.

The story branch already sat before group routing, which is what keeps a
group story out of the conversation — filed there it would be a story
that is a message, and one that never expires out of the thread. That
ordering is now written down rather than incidental.

⚠️ `gid` is persisted, or a reload forgets which story went where.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
Paul Hitt
2026-09-02 17:53:48 -04:00
co-authored by Claude Opus 4.8
parent 6b2896db86
commit b43be1b780
5 changed files with 251 additions and 1 deletions
@@ -0,0 +1,95 @@
package io.flamenet.e2e
import kotlin.test.Test
import kotlin.test.assertEquals
import kotlin.test.assertTrue
/**
* Stories posted to a group (spec §6.24, ios#55).
*
* 🔴 **The group's roster is the audience, and the sender's story audience does
* not apply.** Two different lists making two different statements — who may
* see this account's stories, and who is in a conversation. They will disagree,
* and the roster wins.
*/
class GroupStoryTest {
@Test
fun `every member but yourself is a recipient`() {
val reach = Vault.groupStoryReach(
members = listOf(1, 2, 3), me = 1,
allowedByAudience = setOf(2, 3), contacts = listOf(2, 3))
assertEquals(listOf(2L, 3L), reach.recipients)
}
/**
* 🔴 The hazard the disclosure exists for: somebody excluded from this
* account's stories still receives a story posted to a group they are in.
*/
@Test
fun `a member excluded from your stories still receives a group story`() {
val reach = Vault.groupStoryReach(
members = listOf(1, 2, 3), me = 1,
allowedByAudience = setOf(2), contacts = listOf(2, 3))
assertEquals(listOf(2L, 3L), reach.recipients)
assertEquals(listOf(3L), reach.excludedByAudience)
}
/** The other half: a member who is not a contact at all. */
@Test
fun `a member who is not a contact is named separately`() {
val reach = Vault.groupStoryReach(
members = listOf(1, 2, 9), me = 1,
allowedByAudience = setOf(2), contacts = listOf(2))
assertEquals(listOf(9L), reach.notContacts)
assertTrue(reach.excludedByAudience.isEmpty())
}
/**
* ⚠️ The categories must not double-count. Somebody who is not a contact
* is not "excluded from your stories" — they were never on that list.
*/
@Test
fun `a non-contact is not also counted as excluded`() {
val reach = Vault.groupStoryReach(
members = listOf(1, 9), me = 1,
allowedByAudience = emptySet(), contacts = emptyList())
assertEquals(listOf(9L), reach.notContacts)
assertTrue(reach.excludedByAudience.isEmpty())
}
@Test
fun `nothing is disclosed when the lists agree`() {
val reach = Vault.groupStoryReach(
members = listOf(1, 2), me = 1,
allowedByAudience = setOf(2), contacts = listOf(2))
assertTrue(reach.excludedByAudience.isEmpty())
assertTrue(reach.notContacts.isEmpty())
}
// -- Storage --------------------------------------------------------------
private class MapStorage : Vault.Storage {
val records = LinkedHashMap<String, ByteArray>()
override fun read(name: String) = records[name]
override fun write(name: String, bytes: ByteArray) { records[name] = bytes }
override fun delete(name: String) { records.remove(name) }
override fun names() = records.keys.toList()
}
/** ⚠️ Without persisting `gid`, a reload forgets which story went where. */
@Test
fun `the group survives the vault round trip`() {
val vault = Vault(MapStorage(),
javax.crypto.KeyGenerator.getInstance("AES").apply { init(256) }.generateKey())
val now = System.currentTimeMillis() / 1000.0
vault.saveStories(listOf(Vault.Story(
id = "s1", authorId = 7, mine = false,
ref = Attachment.Ref(
kind = Attachment.STORY, id = "b1", key = ByteArray(32),
digest = ByteArray(32), bytes = 1, mime = "image/jpeg",
width = 1, height = 1, duration = 0.0, expires = now + 600),
caption = "", postedAt = 1, gid = "g1")), now)
assertEquals("g1", vault.loadStories().single().gid)
}
}