amethyst/cli/DEVELOPMENT.md

Developing Amy

How to touch the cli/ module without breaking its public contract.

• What Amy is and what's already shipped: README.md.
• What to build next and in what order: ROADMAP.md.
• Plans for cross-cutting work: see this module's plans/ folder and commons/plans/ for shared-code work consumed by Amy.

The rule this doc defends: cli/ is a thin assembly layer. If you're writing Nostr protocol logic, filter building, state machines, or encryption in here, stop — that code belongs in quartz/ or commons/.

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Design principles

1. Non-interactive. One verb = one JSON object on stdout = one exit code. No REPL, no daemon, no prompts. Any network wait is an explicit await verb with a --timeout.
2. Thin command layer. Each file in commands/ parses args, calls into commons/ or quartz/, and prints JSON. A file longer than ~200 lines is a code smell — the logic is living in the wrong module.
3. Everything persistent is on-disk. No in-memory caches that survive between invocations. Every run reloads cursors, MLS state, identity, and relay config. This is what makes Amy safe to run from CI and from 100 parallel interop scenarios.
4. Shared defaults. When Amethyst picks a default relay, kind, or tag — Amy calls the same helper. No hand-rolled duplicates. If the helper doesn't exist yet, extract it to commons/ first.
5. JSON is the public API. Output-shape changes are breaking changes. Version them explicitly in commit messages; update interop fixtures.

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Architecture

cli/src/main/kotlin/com/vitorpamplona/amethyst/cli/
├── Main.kt                    # argv → subcommand dispatch
├── Args.kt                    # tiny flag parser (no framework)
├── Json.kt                    # single-line stdout + error printer
├── Config.kt                  # Identity, RunState, DataDir
├── Context.kt                 # per-run wiring: signer + NostrClient +
│                              #   MarmotManager + publish/drain/sync helpers
├── stores/FileStores.kt       # File-backed MLS / KP / message stores
└── commands/
    ├── Commands.kt            # dispatcher
    ├── InitCommands.kt        # init, whoami
    ├── CreateCommand.kt       # full bootstrap (→ commons/account/)
    ├── LoginCommand.kt        # nsec/ncryptsec/mnemonic/npub/nprofile/hex/nip05
    ├── RelayCommands.kt       # add/list/publish-lists
    ├── KeyPackageCommands.kt  # marmot key-package publish / check
    ├── GroupCommands.kt       # marmot group create/list/show/…
    ├── GroupCreateCommand.kt
    ├── GroupReadCommands.kt
    ├── GroupAddMemberCommand.kt
    ├── GroupMembershipCommands.kt
    ├── GroupMetadataCommands.kt
    ├── MessageCommands.kt     # marmot message send / list
    └── AwaitCommands.kt       # poll-until-condition helpers

Dependencies: :quartz + :commons + kotlinx-coroutines + OkHttp

• Jackson. No Android, no Compose. Amy compiles on any JDK 21 host. Never add a Gradle dependency on :amethyst or :desktopApp.

Context.kt is the backbone. Most commands follow this template:

val ctx = Context.open(dataDir)
try {
    ctx.prepare()               // restore MLS state + connect relays
    ctx.syncIncoming()          // pull new gift-wraps + group events
    // ...call into commons/ or quartz/ to build an event...
    val ack = ctx.publish(event, targets)
    Json.writeLine(mapOf(...))
} finally {
    ctx.close()                 // flush RunState, disconnect
}

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How to add a command

Rule of thumb: no new logic in cli/. Every command is an assembly of things that already work elsewhere.

1. Audit (mandatory)

Before writing anything, answer three questions:

1. Is the Nostr-protocol piece (event kind, tags, encryption) already in quartz/? If not, add it there first.
2. Is the business logic (state, default values, ordering, filter assembly) already in commons/? If not, extract it from amethyst/ into commons/ in a preceding commit. See the extraction recipe below.
3. What is the smallest signed event or query this command has to produce? That shape is the JSON your command will echo.

2. Extract from Android

The single most important recurring task for Amy's growth. Most Amethyst features today live in amethyst/src/main/java/…/model/ or …/service/ with Android-only imports (Context, SharedPreferences, WorkManager, Log, Bitmap). Amy cannot call those directly — they have to move.

1. Identify the class in amethyst/ (e.g. ReactionPost.kt).
2. List its Android dependencies.
3. For each dependency, choose:
   • Inline-able (one call, trivial): delete.
   • Platform-abstractable: add expect/actual in commons/commonMain/… + commons/androidMain/… + commons/jvmMain/…. (See kotlin-multiplatform skill.)
   • Inversion-of-control: take it as a constructor arg. Amy supplies a JVM flavour.
4. Move the file to commons/commonMain/….
5. Update the Android caller to use the new location. Add a JVM test.
6. Only now, add the cli/commands/… file that calls it.

What to keep in amethyst/: screens, navigation, Android-specific side-effects (notifications, background services, camera, Intents). Everything else is a candidate to move.

3. Command file template

package com.vitorpamplona.amethyst.cli.commands

import com.vitorpamplona.amethyst.cli.Args
import com.vitorpamplona.amethyst.cli.Context
import com.vitorpamplona.amethyst.cli.DataDir
import com.vitorpamplona.amethyst.cli.Json

object NoteCommands {
    suspend fun dispatch(dataDir: DataDir, tail: Array<String>): Int {
        if (tail.isEmpty()) return Json.error("bad_args", "note <publish|read|…>")
        val rest = tail.drop(1).toTypedArray()
        return when (tail[0]) {
            "publish" -> publish(dataDir, rest)
            else -> Json.error("bad_args", "note ${tail[0]}")
        }
    }

    private suspend fun publish(dataDir: DataDir, rest: Array<String>): Int {
        val args = Args(rest)
        val text = args.positional(0, "text")
        val ctx = Context.open(dataDir)
        try {
            ctx.prepare()
            val event = com.vitorpamplona.amethyst.commons.note.buildTextNote(ctx.signer, text)
            val ack = ctx.publish(event, ctx.outboxRelays())
            Json.writeLine(mapOf(
                "event_id" to event.id,
                "kind" to event.kind,
                "published_to" to ack.filterValues { it }.keys.map { it.url },
            ))
            return 0
        } finally { ctx.close() }
    }
}

Wire it into Commands.kt, add a top-level branch in Main.kt's dispatch, and extend printUsage(). Keep README.md's command table and ROADMAP.md's parity matrix in sync.

4. Output-shape conventions

• Top-level object always.
• Stable snake_case keys.
• Event IDs as hex strings (not npub-style).
• Pubkeys as hex ("pubkey":…) and bech32 when the pubkey is the primary subject ("npub":…).
• Relay URLs as strings, normalized, never objects.
• Lists of events under a plural key ("messages", "members").
• Errors via Json.error("code","detail") — single lower_snake code, free-form detail.

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Testing

Most of what Amy does is already exercised by tests in quartz and commons — the protocol, the builders, the state machines. The thin Amy-specific layer still needs its own coverage:

Layer	Test approach
Argument parsing (Args, flag forms, --data-dir=… vs --data-dir …)	Plain JVM unit tests in cli/src/test/kotlin/.
Error / exit-code contract (bad args → 2, await timeout → 124, runtime → 1)	Table-driven tests invoking main(argv) with captured stdout/stderr.
JSON output shape (each command's keys and types)	Snapshot tests: run a command against a throwaway data-dir, assert the JSON matches a golden file.
File layout on disk (identity.json, events-store/…, marmot/groups/*.mls, marmot/keypackages.bundle)	Structural assertions after a command sequence.
Round-trip between two data-dirs on a local relay	End-to-end shell harnesses under cli/tests/. Each harness spins up a local nostr-rs-relay, bootstraps two or more fresh identities in their own --data-dirs, and drives a scenario via amy (+ wn for Marmot interop against whitenoise-rs). Today there are two suites: cli/tests/marmot/ (13 MLS scenarios vs whitenoise-rs) and cli/tests/dm/ (NIP-17 DM round-trips between two amy clients).
Interop with other clients	Covered by cli/tests/marmot/marmot-interop-headless.sh (drives Amy against whitenoise-rs wn/wnd). Add new scenarios there or start a new sibling under cli/tests/.

What not to test here: event signing, filter assembly, MLS correctness, NIP-44 encryption. Those belong in quartz/commons. If an Amy bug can only be caught here, it's a contract violation (wrong key name, wrong exit code), not a protocol bug.

Interop-test script template:

The canonical examples live under cli/tests/ — read cli/tests/README.md for the layout, then crib from cli/tests/dm/tests-dm.sh or cli/tests/marmot/tests-create.sh. At the byte-banging level, a minimal round-trip looks like:

set -euo pipefail
TMP=$(mktemp -d)
A=$TMP/alice; B=$TMP/bob

amy --data-dir "$A" create --name Alice
amy --data-dir "$B" create --name Bob

# ... the scenario under test ...

amy --data-dir "$B" marmot await message "$GID" --match "hello" --timeout 60

If an Amethyst scenario cannot be scripted through Amy yet, that's a gap — add it to ROADMAP.md.

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Housekeeping

• Run ./gradlew spotlessApply before every commit.
• Keep three things in sync: printUsage() in Main.kt, the command table in README.md, and the parity matrix in ROADMAP.md. They drift fast.
• Never add a Gradle dependency on :amethyst or :desktopApp. If you need something from there, move it to commons/ first.
• Never introduce a blocking prompt (readLine(), interactive password input). Take it as a flag.
• Keep each command file small. Past ~200 lines, split — the Marmot group verbs are already a cautionary tale.