First migration of an existing built-in platform adapter to the plugin
system established by IRC / Teams / LINE / Google Chat. Closes#24325;
advances the umbrella refactor in #3823.
Matches Teams' shape exactly — adapter under ``plugins/platforms/discord/``
with the standard ``__init__.py`` / ``adapter.py`` / ``plugin.yaml``
shell, ``register(ctx)`` entry point, **no back-compat shim** at the old
import path, and full parity for the four hooks Teams uses plus the
``apply_yaml_config_fn`` hook that landed in #25443 (the Discord plugin
is the first consumer of that hook):
* ``standalone_sender_fn`` — out-of-process cron delivery via REST API
* ``setup_fn`` — interactive ``hermes setup gateway`` wizard
* ``apply_yaml_config_fn`` — translate ``config.yaml`` ``discord:`` keys
into ``DISCORD_*`` env vars (replaces the hardcoded block in
``gateway/config.py``)
* ``is_connected`` — declares connection state from ``DISCORD_BOT_TOKEN``
* ``check_fn`` — lazy-installs ``discord.py`` on demand
* plus ``allowed_users_env``, ``allow_all_env``, ``cron_deliver_env_var``,
``max_message_length``, ``emoji``, ``required_env``, ``install_hint``
* ``gateway/platforms/discord.py`` (5,101 LOC) →
``plugins/platforms/discord/adapter.py`` (git rename, R090).
* New ``plugins/platforms/discord/{__init__.py, plugin.yaml}`` with
``requires_env`` / ``optional_env`` declarations.
* Append ``register(ctx)`` block + new hook implementations
(``_standalone_send``, ``interactive_setup``, ``_apply_yaml_config``,
``_clean_discord_user_ids``, ``_is_connected``, ``_build_adapter``,
plus helpers ``_DISCORD_CHANNEL_TYPE_PROBE_CACHE`` etc.) to the
adapter.
* Replace the ``Platform.DISCORD elif`` branch in
``GatewayRunner._create_adapter()`` (−9 LOC) with a generic post-creation
hook (+6 LOC) in the registry path: any plugin adapter that declares a
``gateway_runner`` attribute now gets it auto-injected. Webhook's
built-in branch is unchanged (it doesn't go through the registry path).
* Move ``_send_discord`` (190 LOC) and helpers
(``_DISCORD_CHANNEL_TYPE_PROBE_CACHE``, ``_remember_channel_is_forum``,
``_probe_is_forum_cached``, ``_derive_forum_thread_name``) from
``tools/send_message_tool.py`` into the plugin as ``_standalone_send``.
* Wire via ``standalone_sender_fn=_standalone_send`` (Teams pattern; same
gap fixed in #21804 for other plugin platforms).
* Replace the Discord ``elif`` in ``tools/send_message_tool.py``
``_send_to_platform`` with a 10-line registry-hook dispatch.
* Drop the ``DiscordAdapter`` import and the
``Platform.DISCORD: DiscordAdapter.MAX_MESSAGE_LENGTH`` ``_MAX_LENGTHS``
entry — the registry's ``max_message_length=2000`` covers it.
* Move ``_setup_discord`` and ``_clean_discord_user_ids`` (68 LOC) from
``hermes_cli/setup.py`` into the plugin as ``interactive_setup``.
* Wire via ``setup_fn=interactive_setup``. CLI helpers (``prompt``,
``print_info``, etc.) are lazy-imported so the plugin's module-load
surface stays minimal.
* Remove ``"discord": _s._setup_discord`` from
``hermes_cli/gateway.py::_builtin_setup_fn``.
* Remove the entire 32-line ``_PLATFORMS["discord"]`` static dict entry —
Discord's setup metadata is now discovered dynamically via
``_all_platforms()`` from the registry entry.
* Move the 59-line ``discord_cfg`` YAML→env bridge from
``gateway/config.py::load_gateway_config()`` into the plugin as
``_apply_yaml_config``. Covers ``require_mention``,
``thread_require_mention``, ``free_response_channels``, ``auto_thread``,
``reactions``, ``ignored_channels``, ``allowed_channels``,
``no_thread_channels``, ``allow_mentions.{everyone,roles,users,
replied_user}``, and ``reply_to_mode`` (including the YAML 1.1
``off``-as-False coercion and the ``extra.reply_to_mode`` fallback).
* Wire via ``apply_yaml_config_fn=_apply_yaml_config``.
* The hook runs BEFORE ``_apply_env_overrides`` and after the generic
shared-key loop, exactly as documented in
``website/docs/developer-guide/adding-platform-adapters.md``.
* Behavior is preserved exactly — every assignment still uses
``not os.getenv(...)`` guards so env vars take precedence over YAML.
All 78 references to the old import path are rewritten — no back-compat
shim:
* 51 ``from gateway.platforms.discord import X`` →
``from plugins.platforms.discord.adapter import X``
* 5 ``import gateway.platforms.discord as discord_platform`` →
``import plugins.platforms.discord.adapter as discord_platform``
* 1 ``from gateway.platforms import discord as discord_mod`` →
``from plugins.platforms.discord import adapter as discord_mod``
* 21 ``mock.patch("gateway.platforms.discord.X")`` strings →
``mock.patch("plugins.platforms.discord.adapter.X")``
* 1 docstring reference in ``hermes_cli/commands.py``
* 1 import in ``tools/send_message_tool.py`` (now removed entirely)
The import-safety test in ``tests/gateway/test_discord_imports.py`` is
updated to purge the new canonical module name from ``sys.modules``.
**38 files changed, +621 / −473** — net positive due to the YAML hook
implementation (89 new LOC in the plugin trading for 59 deleted in core),
but every line moved has a clear plugin home now. The git rename is
detected at R090 because the adapter gained ~340 LOC of moved-in hook
implementations (``_standalone_send`` + ``interactive_setup`` +
``_apply_yaml_config`` + helpers).
* All 568 Discord-specific tests pass across 25 ``test_discord_*.py``
files plus voice/send/text-batching/reload-skills/stream-consumer/
integration tests.
* All 147 tests in the YAML-touching subset
(``test_discord_reply_mode``, ``test_discord_free_response``,
``test_discord_allowed_channels``, ``test_discord_allowed_mentions``,
``test_discord_channel_controls``, ``test_discord_reactions``,
``test_discord_thread_persistence``, ``test_runtime_footer``) pass —
this is the strongest signal that the YAML→env hook behaves
identically to the legacy block.
* Broader gateway/cron/integration sweep (1297 tests) introduces zero
new failures vs ``main``. Pre-existing failures in
``tests/gateway/test_tts_media_routing.py`` and
``tests/e2e/test_platform_commands.py`` reproduce identically on the
unchanged ``main`` revision.
* Plugin discovery sanity check confirms Discord registers alongside the
other four platform plugins:
Registered platforms: ['discord', 'google_chat', 'irc', 'line', 'teams']
These Discord-shaped tendrils in core were **deliberately not moved** —
they are generic platform-registry concerns affecting every platform,
not Discord-specific:
* ``gateway/config.py:1205`` ``DISCORD_BOT_TOKEN → config.token`` env
enablement — same shape Telegram has. The existing
``env_enablement_fn`` registry hook only seeds ``extra``, not
``.token``, so it can't replace this without an adapter refactor to
read from ``extra["bot_token"]``.
* ``gateway/run.py`` voice-mode hooks
(``self.adapters.get(Platform.DISCORD)`` for
``start_voice_mode``/``stop_voice_mode``), role-based auth,
``DISCORD_ALLOW_BOTS`` branch in ``_is_user_authorized``,
``_UPDATE_ALLOWED_PLATFORMS`` frozenset, and the per-platform
allowlist maps — generic platform-registry concerns.
* ``Platform.DISCORD`` enum literal — stable identifier used as dict
keys throughout the codebase; removing it is a separate refactor with
no real benefit.
* ``tools/discord_tool.py`` and ``tools/environments/local.py`` —
first-class agent tools and env-passthrough config, neither is the
gateway adapter.
Each of these is worth its own scoping issue when the time comes.