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<main>
<article id="content">
<header>
<h1 class="title">Module <code>slack_bolt.async_app</code></h1>
</header>
<section id="section-intro">
<p>Module for creating asyncio based apps</p>
<h3 id="creating-an-async-app">Creating an async app</h3>
<p>If you'd prefer to build your app with <a href="https://docs.python.org/3/library/asyncio.html">asyncio</a>, you can import the <a href="https://docs.aiohttp.org/en/stable/">AIOHTTP</a> library and call the <code><a title="slack_bolt.async_app.AsyncApp" href="#slack_bolt.async_app.AsyncApp">AsyncApp</a></code> constructor. Within async apps, you can use the async/await pattern.</p>
<pre><code class="language-bash"># Python 3.6+ required
python -m venv .venv
source .venv/bin/activate
pip install -U pip
# aiohttp is required
pip install slack_bolt aiohttp
</code></pre>
<p>In async apps, all middleware/listeners must be async functions. When calling utility methods (like <code>ack</code> and <code>say</code>) within these functions, it's required to use the <code>await</code> keyword.</p>
<pre><code class="language-python"># Import the async app instead of the regular one
from slack_bolt.async_app import AsyncApp
app = AsyncApp()
@app.event("app_mention")
async def event_test(body, say, logger):
logger.info(body)
await say("What's up?")
@app.command("/hello-bolt-python")
async def command(ack, body, respond):
await ack()
await respond(f"Hi <@{body['user_id']}>!")
if __name__ == "__main__":
app.start(3000)
</code></pre>
<p>If you want to use another async Web framework (e.g., Sanic, FastAPI, Starlette), take a look at the built-in adapters and their examples.</p>
<ul>
<li><a href="https://github.com/slackapi/bolt-python/tree/main/examples">The Bolt app examples</a></li>
<li><a href="https://github.com/slackapi/bolt-python/tree/main/slack_bolt/adapter">The built-in adapters</a>
Apps can be run the same way as the synchronous example above. If you'd prefer another async Web framework (e.g., Sanic, FastAPI, Starlette), take a look at <a href="https://github.com/slackapi/bolt-python/tree/main/slack_bolt/adapter">the built-in adapters</a> and their corresponding <a href="https://github.com/slackapi/bolt-python/tree/main/examples">examples</a>.</li>
</ul>
<p>Refer to <code><a title="slack_bolt.app.async_app" href="app/async_app.html">slack_bolt.app.async_app</a></code> for more details.</p>
</section>
<section>
</section>
<section>
</section>
<section>
</section>
<section>
<h2 class="section-title" id="header-classes">Classes</h2>
<dl>
<dt id="slack_bolt.async_app.AsyncAck"><code class="flex name class">
<span>class <span class="ident">AsyncAck</span></span>
</code></dt>
<dd>
<details class="source">
<summary>
<span>Expand source code</span>
</summary>
<pre><code class="python">class AsyncAck:
response: Optional[BoltResponse]
def __init__(self):
self.response: Optional[BoltResponse] = None
async def __call__(
self,
text: Union[str, dict] = "", # text: str or whole_response: dict
blocks: Optional[Sequence[Union[dict, Block]]] = None,
attachments: Optional[Sequence[Union[dict, Attachment]]] = None,
unfurl_links: Optional[bool] = None,
unfurl_media: Optional[bool] = None,
response_type: Optional[str] = None, # in_channel / ephemeral
# block_suggestion / dialog_suggestion
options: Optional[Sequence[Union[dict, Option]]] = None,
option_groups: Optional[Sequence[Union[dict, OptionGroup]]] = None,
# view_submission
response_action: Optional[str] = None, # errors / update / push / clear
errors: Optional[Dict[str, str]] = None,
view: Optional[Union[dict, View]] = None,
) -> BoltResponse:
return _set_response(
self,
text_or_whole_response=text,
blocks=blocks,
attachments=attachments,
unfurl_links=unfurl_links,
unfurl_media=unfurl_media,
response_type=response_type,
options=options,
option_groups=option_groups,
response_action=response_action,
errors=errors,
view=view,
)</code></pre>
</details>
<div class="desc"></div>
<h3>Class variables</h3>
<dl>
<dt id="slack_bolt.async_app.AsyncAck.response"><code class="name">var <span class="ident">response</span> : <a title="slack_bolt.response.response.BoltResponse" href="response/response.html#slack_bolt.response.response.BoltResponse">BoltResponse</a> | None</code></dt>
<dd>
<div class="desc"><p>The type of the None singleton.</p></div>
</dd>
</dl>
</dd>
<dt id="slack_bolt.async_app.AsyncApp"><code class="flex name class">
<span>class <span class="ident">AsyncApp</span></span>
<span>(</span><span>*,<br>logger: logging.Logger | None = None,<br>name: str | None = None,<br>process_before_response: bool = False,<br>raise_error_for_unhandled_request: bool = False,<br>signing_secret: str | None = None,<br>token: str | None = None,<br>client: slack_sdk.web.async_client.AsyncWebClient | None = None,<br>before_authorize: <a title="slack_bolt.middleware.async_middleware.AsyncMiddleware" href="middleware/async_middleware.html#slack_bolt.middleware.async_middleware.AsyncMiddleware">AsyncMiddleware</a> | Callable[..., Awaitable[Any]] | None = None,<br>authorize: Callable[..., Awaitable[<a title="slack_bolt.authorization.authorize_result.AuthorizeResult" href="authorization/authorize_result.html#slack_bolt.authorization.authorize_result.AuthorizeResult">AuthorizeResult</a>]] | None = None,<br>user_facing_authorize_error_message: str | None = None,<br>installation_store: slack_sdk.oauth.installation_store.async_installation_store.AsyncInstallationStore | None = None,<br>installation_store_bot_only: bool | None = None,<br>request_verification_enabled: bool = True,<br>ignoring_self_events_enabled: bool = True,<br>ignoring_self_assistant_message_events_enabled: bool = True,<br>ssl_check_enabled: bool = True,<br>url_verification_enabled: bool = True,<br>attaching_function_token_enabled: bool = True,<br>oauth_settings: <a title="slack_bolt.oauth.async_oauth_settings.AsyncOAuthSettings" href="oauth/async_oauth_settings.html#slack_bolt.oauth.async_oauth_settings.AsyncOAuthSettings">AsyncOAuthSettings</a> | None = None,<br>oauth_flow: <a title="slack_bolt.oauth.async_oauth_flow.AsyncOAuthFlow" href="oauth/async_oauth_flow.html#slack_bolt.oauth.async_oauth_flow.AsyncOAuthFlow">AsyncOAuthFlow</a> | None = None,<br>verification_token: str | None = None,<br>assistant_thread_context_store: <a title="slack_bolt.context.assistant.thread_context_store.async_store.AsyncAssistantThreadContextStore" href="context/assistant/thread_context_store/async_store.html#slack_bolt.context.assistant.thread_context_store.async_store.AsyncAssistantThreadContextStore">AsyncAssistantThreadContextStore</a> | None = None)</span>
</code></dt>
<dd>
<details class="source">
<summary>
<span>Expand source code</span>
</summary>
<pre><code class="python">class AsyncApp:
def __init__(
self,
*,
logger: Optional[logging.Logger] = None,
# Used in logger
name: Optional[str] = None,
# Set True when you run this app on a FaaS platform
process_before_response: bool = False,
# Set True if you want to handle an unhandled request as an exception
raise_error_for_unhandled_request: bool = False,
# Basic Information > Credentials > Signing Secret
signing_secret: Optional[str] = None,
# for single-workspace apps
token: Optional[str] = None,
client: Optional[AsyncWebClient] = None,
# for multi-workspace apps
before_authorize: Optional[Union[AsyncMiddleware, Callable[..., Awaitable[Any]]]] = None,
authorize: Optional[Callable[..., Awaitable[AuthorizeResult]]] = None,
user_facing_authorize_error_message: Optional[str] = None,
installation_store: Optional[AsyncInstallationStore] = None,
# for either only bot scope usage or v1.0.x compatibility
installation_store_bot_only: Optional[bool] = None,
# for customizing the built-in middleware
request_verification_enabled: bool = True,
ignoring_self_events_enabled: bool = True,
ignoring_self_assistant_message_events_enabled: bool = True,
ssl_check_enabled: bool = True,
url_verification_enabled: bool = True,
attaching_function_token_enabled: bool = True,
# for the OAuth flow
oauth_settings: Optional[AsyncOAuthSettings] = None,
oauth_flow: Optional[AsyncOAuthFlow] = None,
# No need to set (the value is used only in response to ssl_check requests)
verification_token: Optional[str] = None,
# for AI Agents & Assistants
assistant_thread_context_store: Optional[AsyncAssistantThreadContextStore] = None,
):
"""Bolt App that provides functionalities to register middleware/listeners.
import os
from slack_bolt.async_app import AsyncApp
# Initializes your app with your bot token and signing secret
app = AsyncApp(
token=os.environ.get("SLACK_BOT_TOKEN"),
signing_secret=os.environ.get("SLACK_SIGNING_SECRET")
)
# Listens to incoming messages that contain "hello"
@app.message("hello")
async def message_hello(message, say): # async function
# say() sends a message to the channel where the event was triggered
await say(f"Hey there <@{message['user']}>!")
# Start your app
if __name__ == "__main__":
app.start(port=int(os.environ.get("PORT", 3000)))
Refer to https://slack.dev/bolt-python/concepts#async for details.
If you would like to build an OAuth app for enabling the app to run with multiple workspaces,
refer to https://slack.dev/bolt-python/concepts#authenticating-oauth to learn how to configure the app.
Args:
logger: The custom logger that can be used in this app.
name: The application name that will be used in logging. If absent, the source file name will be used.
process_before_response: True if this app runs on Function as a Service. (Default: False)
raise_error_for_unhandled_request: True if you want to raise exceptions for unhandled requests
and use @app.error listeners instead of
the built-in handler, which pints warning logs and returns 404 to Slack (Default: False)
signing_secret: The Signing Secret value used for verifying requests from Slack.
token: The bot/user access token required only for single-workspace app.
client: The singleton `slack_sdk.web.async_client.AsyncWebClient` instance for this app.
before_authorize: A global middleware that can be executed right before authorize function
authorize: The function to authorize an incoming request from Slack
by checking if there is a team/user in the installation data.
user_facing_authorize_error_message: The user-facing error message to display
when the app is installed but the installation is not managed by this app's installation store
installation_store: The module offering save/find operations of installation data
installation_store_bot_only: Use `AsyncInstallationStore#async_find_bot()` if True (Default: False)
request_verification_enabled: False if you would like to disable the built-in middleware (Default: True).
`AsyncRequestVerification` is a built-in middleware that verifies the signature in HTTP Mode requests.
Make sure if it's safe enough when you turn a built-in middleware off.
We strongly recommend using RequestVerification for better security.
If you have a proxy that verifies request signature in front of the Bolt app,
it's totally fine to disable RequestVerification to avoid duplication of work.
Don't turn it off just for easiness of development.
ignoring_self_events_enabled: False if you would like to disable the built-in middleware (Default: True).
`AsyncIgnoringSelfEvents` is a built-in middleware that enables Bolt apps to easily skip the events
generated by this app's bot user (this is useful for avoiding code error causing an infinite loop).
ignoring_self_assistant_message_events_enabled: False if you would like to disable the built-in middleware.
`IgnoringSelfEvents` for this app's bot user message events within an assistant thread
This is useful for avoiding code error causing an infinite loop; Default: True
url_verification_enabled: False if you would like to disable the built-in middleware (Default: True).
`AsyncUrlVerification` is a built-in middleware that handles url_verification requests
that verify the endpoint for Events API in HTTP Mode requests.
ssl_check_enabled: bool = False if you would like to disable the built-in middleware (Default: True).
`AsyncSslCheck` is a built-in middleware that handles ssl_check requests from Slack.
attaching_function_token_enabled: False if you would like to disable the built-in middleware (Default: True).
`AsyncAttachingFunctionToken` is a built-in middleware that injects the just-in-time workflow-execution token
when your app receives `function_executed` or interactivity events scoped to a custom step.
oauth_settings: The settings related to Slack app installation flow (OAuth flow)
oauth_flow: Instantiated `slack_bolt.oauth.AsyncOAuthFlow`. This is always prioritized over oauth_settings.
verification_token: Deprecated verification mechanism. This can be used only for ssl_check requests.
assistant_thread_context_store: Custom AssistantThreadContext store (Default: the built-in implementation,
which uses a parent message's metadata to store the latest context)
"""
if signing_secret is None:
signing_secret = os.environ.get("SLACK_SIGNING_SECRET", "")
token = token or os.environ.get("SLACK_BOT_TOKEN")
self._name: str = name or inspect.stack()[1].filename.split(os.path.sep)[-1]
self._signing_secret: str = signing_secret
self._verification_token: Optional[str] = verification_token or os.environ.get("SLACK_VERIFICATION_TOKEN", None)
# If a logger is explicitly passed when initializing, the logger works as the base logger.
# The base logger's logging settings will be propagated to all the loggers created by bolt-python.
self._base_logger = logger
# The framework logger is supposed to be used for the internal logging.
# Also, it's accessible via `app.logger` as the app's singleton logger.
self._framework_logger = logger or get_bolt_logger(AsyncApp)
self._raise_error_for_unhandled_request = raise_error_for_unhandled_request
self._token: Optional[str] = token
if client is not None:
if not isinstance(client, AsyncWebClient):
raise BoltError(error_client_invalid_type_async())
self._async_client = client
self._token = client.token
if token is not None:
self._framework_logger.warning(warning_client_prioritized_and_token_skipped())
else:
self._async_client = create_async_web_client(
# NOTE: the token here can be None
token=token,
logger=self._framework_logger,
)
# --------------------------------------
# Authorize & OAuthFlow initialization
# --------------------------------------
self._async_before_authorize: Optional[AsyncMiddleware] = None
if before_authorize is not None:
if callable(before_authorize):
self._async_before_authorize = AsyncCustomMiddleware(
app_name=self._name,
func=before_authorize,
base_logger=self._framework_logger,
)
elif isinstance(before_authorize, AsyncMiddleware):
self._async_before_authorize = before_authorize
self._async_authorize: Optional[AsyncAuthorize] = None
if authorize is not None:
if isinstance(authorize, AsyncAuthorize):
# As long as an advanced developer understands what they're doing,
# bolt-python should not prevent customizing authorize middleware
self._async_authorize = authorize
else:
if oauth_settings is not None or oauth_flow is not None:
# If the given authorize is a simple function,
# it does not work along with installation_store.
raise BoltError(error_authorize_conflicts())
self._async_authorize = AsyncCallableAuthorize(logger=self._framework_logger, func=authorize)
self._async_installation_store: Optional[AsyncInstallationStore] = installation_store
if self._async_installation_store is not None and self._async_authorize is None:
settings = oauth_flow.settings if oauth_flow is not None else oauth_settings
self._async_authorize = AsyncInstallationStoreAuthorize(
installation_store=self._async_installation_store,
client_id=settings.client_id if settings is not None else None,
client_secret=settings.client_secret if settings is not None else None,
logger=self._framework_logger,
bot_only=installation_store_bot_only or False,
client=self._async_client, # for proxy use cases etc.
user_token_resolution=(settings.user_token_resolution if settings is not None else "authed_user"),
)
self._async_oauth_flow: Optional[AsyncOAuthFlow] = None
if (
oauth_settings is None
and os.environ.get("SLACK_CLIENT_ID") is not None
and os.environ.get("SLACK_CLIENT_SECRET") is not None
):
# initialize with the default settings
oauth_settings = AsyncOAuthSettings()
if oauth_flow is None and installation_store is None:
# show info-level log for avoiding confusions
self._framework_logger.info(info_default_oauth_settings_loaded())
if oauth_flow:
if not isinstance(oauth_flow, AsyncOAuthFlow):
raise BoltError(error_oauth_flow_invalid_type_async())
self._async_oauth_flow = oauth_flow
installation_store = select_consistent_installation_store(
client_id=self._async_oauth_flow.client_id,
app_store=self._async_installation_store,
oauth_flow_store=self._async_oauth_flow.settings.installation_store,
logger=self._framework_logger,
)
self._async_installation_store = installation_store
if installation_store is not None:
self._async_oauth_flow.settings.installation_store = installation_store
if self._async_oauth_flow._async_client is None:
self._async_oauth_flow._async_client = self._async_client
if self._async_authorize is None:
self._async_authorize = self._async_oauth_flow.settings.authorize
elif oauth_settings is not None:
if not isinstance(oauth_settings, AsyncOAuthSettings):
raise BoltError(error_oauth_settings_invalid_type_async())
installation_store = select_consistent_installation_store(
client_id=oauth_settings.client_id,
app_store=self._async_installation_store,
oauth_flow_store=oauth_settings.installation_store,
logger=self._framework_logger,
)
self._async_installation_store = installation_store
if installation_store is not None:
oauth_settings.installation_store = installation_store
self._async_oauth_flow = AsyncOAuthFlow(client=self._async_client, logger=self.logger, settings=oauth_settings)
if self._async_authorize is None:
self._async_authorize = self._async_oauth_flow.settings.authorize
self._async_authorize.token_rotation_expiration_minutes = oauth_settings.token_rotation_expiration_minutes # type: ignore[attr-defined] # noqa: E501
if (self._async_installation_store is not None or self._async_authorize is not None) and self._token is not None:
self._token = None
self._framework_logger.warning(warning_token_skipped())
# after setting bot_only here, __init__ cannot replace authorize function
if installation_store_bot_only is not None and self._async_oauth_flow is not None:
app_bot_only = installation_store_bot_only or False
oauth_flow_bot_only = self._async_oauth_flow.settings.installation_store_bot_only
if app_bot_only != oauth_flow_bot_only:
self.logger.warning(warning_bot_only_conflicts())
self._async_oauth_flow.settings.installation_store_bot_only = app_bot_only
self._async_authorize.bot_only = app_bot_only # type: ignore[union-attr]
self._async_tokens_revocation_listeners: Optional[AsyncTokenRevocationListeners] = None
if self._async_installation_store is not None:
self._async_tokens_revocation_listeners = AsyncTokenRevocationListeners(self._async_installation_store)
# --------------------------------------
# Middleware Initialization
# --------------------------------------
self._async_middleware_list: List[AsyncMiddleware] = []
self._async_listeners: List[AsyncListener] = []
self._assistant_thread_context_store = assistant_thread_context_store
self._process_before_response = process_before_response
self._async_listener_runner = AsyncioListenerRunner(
logger=self._framework_logger,
process_before_response=process_before_response,
listener_error_handler=AsyncDefaultListenerErrorHandler(logger=self._framework_logger),
listener_start_handler=AsyncDefaultListenerStartHandler(logger=self._framework_logger),
listener_completion_handler=AsyncDefaultListenerCompletionHandler(logger=self._framework_logger),
lazy_listener_runner=AsyncioLazyListenerRunner(
logger=self._framework_logger,
),
)
self._async_middleware_error_handler: AsyncMiddlewareErrorHandler = AsyncDefaultMiddlewareErrorHandler(
logger=self._framework_logger,
)
self._init_middleware_list_done = False
self._init_async_middleware_list(
request_verification_enabled=request_verification_enabled,
ignoring_self_events_enabled=ignoring_self_events_enabled,
ignoring_self_assistant_message_events_enabled=ignoring_self_assistant_message_events_enabled,
ssl_check_enabled=ssl_check_enabled,
url_verification_enabled=url_verification_enabled,
attaching_function_token_enabled=attaching_function_token_enabled,
user_facing_authorize_error_message=user_facing_authorize_error_message,
)
self._server: Optional[AsyncSlackAppServer] = None
def _init_async_middleware_list(
self,
request_verification_enabled: bool = True,
ignoring_self_events_enabled: bool = True,
ignoring_self_assistant_message_events_enabled: bool = True,
ssl_check_enabled: bool = True,
url_verification_enabled: bool = True,
attaching_function_token_enabled: bool = True,
user_facing_authorize_error_message: Optional[str] = None,
):
if self._init_middleware_list_done:
return
if ssl_check_enabled is True:
self._async_middleware_list.append(
AsyncSslCheck(
verification_token=self._verification_token,
base_logger=self._base_logger,
)
)
if request_verification_enabled is True:
self._async_middleware_list.append(AsyncRequestVerification(self._signing_secret, base_logger=self._base_logger))
if self._async_before_authorize is not None:
self._async_middleware_list.append(self._async_before_authorize)
# As authorize is required for making a Bolt app function, we don't offer the flag to disable this
if self._async_oauth_flow is None:
if self._token:
self._async_middleware_list.append(
AsyncSingleTeamAuthorization(
base_logger=self._base_logger,
user_facing_authorize_error_message=user_facing_authorize_error_message,
)
)
elif self._async_authorize is not None:
self._async_middleware_list.append(
AsyncMultiTeamsAuthorization(
authorize=self._async_authorize,
base_logger=self._base_logger,
user_facing_authorize_error_message=user_facing_authorize_error_message,
)
)
else:
raise BoltError(error_token_required())
elif self._async_authorize is not None:
self._async_middleware_list.append(
AsyncMultiTeamsAuthorization(
authorize=self._async_authorize,
base_logger=self._base_logger,
user_token_resolution=self._async_oauth_flow.settings.user_token_resolution,
user_facing_authorize_error_message=user_facing_authorize_error_message,
)
)
else:
raise BoltError(error_oauth_flow_or_authorize_required())
if ignoring_self_events_enabled is True:
self._async_middleware_list.append(
AsyncIgnoringSelfEvents(
base_logger=self._base_logger,
ignoring_self_assistant_message_events_enabled=ignoring_self_assistant_message_events_enabled,
)
)
if url_verification_enabled is True:
self._async_middleware_list.append(AsyncUrlVerification(base_logger=self._base_logger))
if attaching_function_token_enabled is True:
self._async_middleware_list.append(AsyncAttachingFunctionToken())
self._init_middleware_list_done = True
# -------------------------
# accessors
@property
def name(self) -> str:
"""The name of this app (default: the filename)"""
return self._name
@property
def oauth_flow(self) -> Optional[AsyncOAuthFlow]:
"""Configured `OAuthFlow` object if exists."""
return self._async_oauth_flow
@property
def client(self) -> AsyncWebClient:
"""The singleton `slack_sdk.web.async_client.AsyncWebClient` instance in this app."""
return self._async_client
@property
def logger(self) -> logging.Logger:
"""The logger this app uses."""
return self._framework_logger
@property
def installation_store(self) -> Optional[AsyncInstallationStore]:
"""The `slack_sdk.oauth.AsyncInstallationStore` that can be used in the `authorize` middleware."""
return self._async_installation_store
@property
def listener_runner(self) -> AsyncioListenerRunner:
"""The asyncio-based executor for asynchronously running listeners."""
return self._async_listener_runner
@property
def process_before_response(self) -> bool:
return self._process_before_response or False
# -------------------------
# standalone server
from .async_server import AsyncSlackAppServer
def server(
self,
port: int = 3000,
path: str = "/slack/events",
host: Optional[str] = None,
) -> AsyncSlackAppServer:
"""Configure a web server using AIOHTTP.
Refer to https://docs.aiohttp.org/ for more details about AIOHTTP.
Args:
port: The port to listen on (Default: 3000)
path: The path to handle request from Slack (Default: `/slack/events`)
host: The hostname to serve the web endpoints. (Default: 0.0.0.0)
"""
if self._server is None or self._server.port != port or self._server.path != path:
self._server = AsyncSlackAppServer(
port=port,
path=path,
app=self,
host=host,
)
return self._server
def web_app(self, path: str = "/slack/events", port: int = 3000) -> web.Application:
"""Returns a `web.Application` instance for aiohttp-devtools users.
from slack_bolt.async_app import AsyncApp
app = AsyncApp()
@app.event("app_mention")
async def event_test(body, say, logger):
logger.info(body)
await say("What's up?")
def app_factory():
return app.web_app()
# adev runserver --port 3000 --app-factory app_factory async_app.py
Args:
path: The path to receive incoming requests from Slack
port: The port to listen on (Default: 3000)
"""
return self.server(path=path, port=port).web_app
def start(self, port: int = 3000, path: str = "/slack/events", host: Optional[str] = None) -> None:
"""Start a web server using AIOHTTP.
Refer to https://docs.aiohttp.org/ for more details about AIOHTTP.
Args:
port: The port to listen on (Default: 3000)
path: The path to handle request from Slack (Default: `/slack/events`)
host: The hostname to serve the web endpoints. (Default: 0.0.0.0)
"""
self.server(port=port, path=path, host=host).start()
# -------------------------
# main dispatcher
async def async_dispatch(self, req: AsyncBoltRequest) -> BoltResponse:
"""Applies all middleware and dispatches an incoming request from Slack to the right code path.
Args:
req: An incoming request from Slack.
Returns:
The response generated by this Bolt app.
"""
starting_time = time.time()
self._init_context(req)
resp: Optional[BoltResponse] = BoltResponse(status=200, body="")
middleware_state = {"next_called": False}
async def async_middleware_next():
middleware_state["next_called"] = True
try:
for middleware in self._async_middleware_list:
middleware_state["next_called"] = False
if self._framework_logger.level <= logging.DEBUG:
self._framework_logger.debug(f"Applying {middleware.name}")
resp = await middleware.async_process(
req=req, resp=resp, next=async_middleware_next # type: ignore[arg-type]
)
if not middleware_state["next_called"]:
if resp is None:
# next() method was not called without providing the response to return to Slack
# This should not be an intentional handling in usual use cases.
resp = BoltResponse(status=404, body={"error": "no next() calls in middleware"})
if self._raise_error_for_unhandled_request is True:
try:
raise BoltUnhandledRequestError(
request=req,
current_response=resp,
last_global_middleware_name=middleware.name,
)
except BoltUnhandledRequestError as e:
await self._async_listener_runner.listener_error_handler.handle(
error=e,
request=req,
response=resp,
)
return resp
self._framework_logger.warning(warning_unhandled_by_global_middleware(middleware.name, req))
return resp
return resp
for listener in self._async_listeners:
listener_name = get_name_for_callable(listener.ack_function)
self._framework_logger.debug(debug_checking_listener(listener_name))
if await listener.async_matches(req=req, resp=resp): # type: ignore[arg-type]
# run all the middleware attached to this listener first
(middleware_resp, next_was_not_called) = await listener.run_async_middleware(
req=req, resp=resp # type: ignore[arg-type]
)
if next_was_not_called:
if middleware_resp is not None:
if self._framework_logger.level <= logging.DEBUG:
debug_message = debug_return_listener_middleware_response(
listener_name,
middleware_resp.status,
middleware_resp.body,
starting_time,
)
self._framework_logger.debug(debug_message)
return middleware_resp
# The last listener middleware didn't call next() method.
# This means the listener is not for this incoming request.
continue
if middleware_resp is not None:
resp = middleware_resp
self._framework_logger.debug(debug_running_listener(listener_name))
listener_response: Optional[BoltResponse] = await self._async_listener_runner.run(
request=req,
response=resp, # type: ignore[arg-type]
listener_name=listener_name,
listener=listener,
)
if listener_response is not None:
return listener_response
if resp is None:
resp = BoltResponse(status=404, body={"error": "unhandled request"})
if self._raise_error_for_unhandled_request is True:
try:
raise BoltUnhandledRequestError(
request=req,
current_response=resp,
)
except BoltUnhandledRequestError as e:
await self._async_listener_runner.listener_error_handler.handle(
error=e,
request=req,
response=resp,
)
return resp
return self._handle_unmatched_requests(req, resp)
except Exception as error:
resp = BoltResponse(status=500, body="")
await self._async_middleware_error_handler.handle(
error=error,
request=req,
response=resp,
)
return resp
def _handle_unmatched_requests(self, req: AsyncBoltRequest, resp: BoltResponse) -> BoltResponse:
self._framework_logger.warning(warning_unhandled_request(req))
return resp
# -------------------------
# middleware
def use(self, *args) -> Optional[Callable]:
"""Refer to `AsyncApp#middleware()` method's docstring for details."""
return self.middleware(*args)
def middleware(self, *args) -> Optional[Callable]:
"""Registers a new middleware to this app.
This method can be used as either a decorator or a method.
# Use this method as a decorator
@app.middleware
async def middleware_func(logger, body, next):
logger.info(f"request body: {body}")
await next()
# Pass a function to this method
app.middleware(middleware_func)
To learn available arguments for middleware/listeners, see `slack_bolt.kwargs_injection.async_args`'s API document.
Args:
*args: A function that works as a global middleware.
"""
if len(args) > 0:
middleware_or_callable = args[0]
if isinstance(middleware_or_callable, AsyncMiddleware):
middleware: AsyncMiddleware = middleware_or_callable
self._async_middleware_list.append(middleware)
if isinstance(middleware, AsyncAssistant) and middleware.thread_context_store is not None:
self._assistant_thread_context_store = middleware.thread_context_store
elif callable(middleware_or_callable):
self._async_middleware_list.append(
AsyncCustomMiddleware(
app_name=self.name,
func=middleware_or_callable,
base_logger=self._base_logger,
)
)
return middleware_or_callable
else:
raise BoltError(f"Unexpected type for a middleware ({type(middleware_or_callable)})")
return None
def assistant(self, assistant: AsyncAssistant) -> Optional[Callable]:
return self.middleware(assistant)
# -------------------------
# Workflows: Steps from apps
def step(
self,
callback_id: Union[str, Pattern, AsyncWorkflowStep, AsyncWorkflowStepBuilder],
edit: Optional[Union[Callable[..., Optional[BoltResponse]], AsyncListener, Sequence[Callable]]] = None,
save: Optional[Union[Callable[..., Optional[BoltResponse]], AsyncListener, Sequence[Callable]]] = None,
execute: Optional[Union[Callable[..., Optional[BoltResponse]], AsyncListener, Sequence[Callable]]] = None,
):
"""
Deprecated:
Steps from apps for legacy workflows are now deprecated.
Use new custom steps: https://api.slack.com/automation/functions/custom-bolt
Registers a new step from app listener.
Unlike others, this method doesn't behave as a decorator.
If you want to register a step from app by a decorator, use `AsyncWorkflowStepBuilder`'s methods.
# Create a new WorkflowStep instance
from slack_bolt.workflows.async_step import AsyncWorkflowStep
ws = AsyncWorkflowStep(
callback_id="add_task",
edit=edit,
save=save,
execute=execute,
)
# Pass Step to set up listeners
app.step(ws)
Refer to https://api.slack.com/workflows/steps for details of steps from apps.
To learn available arguments for middleware/listeners, see `slack_bolt.kwargs_injection.async_args`'s API document.
For further information about AsyncWorkflowStep specific function arguments
such as `configure`, `update`, `complete`, and `fail`,
refer to the `async` prefixed ones in `slack_bolt.workflows.step.utilities` API documents.
Args:
callback_id: The Callback ID for this step from app
edit: The function for displaying a modal in the Workflow Builder
save: The function for handling configuration in the Workflow Builder
execute: The function for handling the step execution
"""
warnings.warn(
(
"Steps from apps for legacy workflows are now deprecated. "
"Use new custom steps: https://api.slack.com/automation/functions/custom-bolt"
),
category=DeprecationWarning,
)
step = callback_id
if isinstance(callback_id, (str, Pattern)):
step = AsyncWorkflowStep(
callback_id=callback_id,
edit=edit, # type: ignore[arg-type]
save=save, # type: ignore[arg-type]
execute=execute, # type: ignore[arg-type]
base_logger=self._base_logger,
)
elif isinstance(step, AsyncWorkflowStepBuilder):
step = step.build(base_logger=self._base_logger)
elif not isinstance(step, AsyncWorkflowStep):
raise BoltError(f"Invalid step object ({type(step)})")
self.use(AsyncWorkflowStepMiddleware(step))
# -------------------------
# global error handler
def error(
self, func: Callable[..., Awaitable[Optional[BoltResponse]]]
) -> Callable[..., Awaitable[Optional[BoltResponse]]]:
"""Updates the global error handler. This method can be used as either a decorator or a method.
# Use this method as a decorator
@app.error
async def custom_error_handler(error, body, logger):
logger.exception(f"Error: {error}")
logger.info(f"Request body: {body}")
# Pass a function to this method
app.error(custom_error_handler)
To learn available arguments for middleware/listeners, see `slack_bolt.kwargs_injection.async_args`'s API document.
Args:
func: The function that is supposed to be executed
when getting an unhandled error in Bolt app.
"""
if not is_callable_coroutine(func):
name = get_name_for_callable(func)
raise BoltError(error_listener_function_must_be_coro_func(name))
self._async_listener_runner.listener_error_handler = AsyncCustomListenerErrorHandler(
logger=self._framework_logger,
func=func,
)
self._async_middleware_error_handler = AsyncCustomMiddlewareErrorHandler(
logger=self._framework_logger,
func=func,
)
return func
# -------------------------
# events
def event(
self,
event: Union[
str,
Pattern,
Dict[str, Optional[Union[str, Sequence[Optional[Union[str, Pattern]]]]]],
],
matchers: Optional[Sequence[Callable[..., Awaitable[bool]]]] = None,
middleware: Optional[Sequence[Union[Callable, AsyncMiddleware]]] = None,
) -> Callable[..., Optional[Callable[..., Awaitable[Optional[BoltResponse]]]]]:
"""Registers a new event listener. This method can be used as either a decorator or a method.
# Use this method as a decorator
@app.event("team_join")
async def ask_for_introduction(event, say):
welcome_channel_id = "C12345"
user_id = event["user"]
text = f"Welcome to the team, <@{user_id}>! :tada: You can introduce yourself in this channel."
await say(text=text, channel=welcome_channel_id)
# Pass a function to this method
app.event("team_join")(ask_for_introduction)
Refer to https://api.slack.com/apis/connections/events-api for details of Events API.
To learn available arguments for middleware/listeners, see `slack_bolt.kwargs_injection.async_args`'s API document.
Args:
event: The conditions that match a request payload.
If you pass a dict for this, you can have type, subtype in the constraint.
matchers: A list of listener matcher functions.
Only when all the matchers return True, the listener function can be invoked.
middleware: A list of lister middleware functions.
Only when all the middleware call `next()` method, the listener function can be invoked.
"""
def __call__(*args, **kwargs):
functions = self._to_listener_functions(kwargs) if kwargs else list(args)
primary_matcher = builtin_matchers.event(event, True, base_logger=self._base_logger)
return self._register_listener(list(functions), primary_matcher, matchers, middleware, True)
return __call__
def message(
self,
keyword: Union[str, Pattern] = "",
matchers: Optional[Sequence[Callable[..., Awaitable[bool]]]] = None,
middleware: Optional[Sequence[Union[Callable, AsyncMiddleware]]] = None,
) -> Callable[..., Optional[Callable[..., Awaitable[Optional[BoltResponse]]]]]:
"""Registers a new message event listener. This method can be used as either a decorator or a method.
Check the `App#event` method's docstring for details.
# Use this method as a decorator
@app.message(":wave:")
async def say_hello(message, say):
user = message['user']
await say(f"Hi there, <@{user}>!")
# Pass a function to this method
app.message(":wave:")(say_hello)
Refer to https://api.slack.com/events/message for details of `message` events.
To learn available arguments for middleware/listeners, see `slack_bolt.kwargs_injection.async_args`'s API document.
Args:
keyword: The keyword to match
matchers: A list of listener matcher functions.
Only when all the matchers return True, the listener function can be invoked.
middleware: A list of lister middleware functions.
Only when all the middleware call `next()` method, the listener function can be invoked.
"""
matchers = list(matchers) if matchers else []
middleware = list(middleware) if middleware else []
def __call__(*args, **kwargs):
functions = self._to_listener_functions(kwargs) if kwargs else list(args)
constraints = {
"type": "message",
"subtype": (
# In most cases, new message events come with no subtype.
None,
# As of Jan 2021, most bot messages no longer have the subtype bot_message.
# By contrast, messages posted using classic app's bot token still have the subtype.
"bot_message",
# If an end-user posts a message with "Also send to #channel" checked,
# the message event comes with this subtype.
"thread_broadcast",
# If an end-user posts a message with attached files,
# the message event comes with this subtype.
"file_share",
),
}
primary_matcher = builtin_matchers.message_event(
constraints=constraints,
keyword=keyword,
asyncio=True,
base_logger=self._base_logger,
)
middleware.insert(0, AsyncMessageListenerMatches(keyword))
return self._register_listener(list(functions), primary_matcher, matchers, middleware, True)
return __call__
def function(
self,
callback_id: Union[str, Pattern],
matchers: Optional[Sequence[Callable[..., Awaitable[bool]]]] = None,
middleware: Optional[Sequence[Union[Callable, AsyncMiddleware]]] = None,
auto_acknowledge: bool = True,
) -> Callable[..., Optional[Callable[..., Awaitable[BoltResponse]]]]:
"""Registers a new Function listener.
This method can be used as either a decorator or a method.
# Use this method as a decorator
@app.function("reverse")
async def reverse_string(ack: AsyncAck, inputs: dict, complete: AsyncComplete, fail: AsyncFail):
try:
await ack()
string_to_reverse = inputs["stringToReverse"]
await complete({"reverseString": string_to_reverse[::-1]})
except Exception as e:
await fail(f"Cannot reverse string (error: {e})")
raise e
# Pass a function to this method
app.function("reverse")(reverse_string)