Add Google Cloud Functions adapter (ref #646) (#649)

Author: seratch

examples/google_cloud_functions/.env.yaml.oauth-sample

@@ -0,0 +1,4 @@
+SLACK_CLIENT_ID: '1111.222'
+SLACK_CLIENT_SECRET: 'xxx'
+SLACK_SIGNING_SECRET: 'yyy'
+SLACK_SCOPES: 'app_mentions:read,chat:write,commands'

examples/google_cloud_functions/.gitignore

@@ -1 +1,2 @@
-.env.yaml
+.env.yaml
+main.py

examples/google_cloud_functions/datastore.py

@@ -0,0 +1,252 @@
+#
+# Please note that this is an example implementation.
+# You can reuse this implementation for your app,
+# but we don't have short-term plans to add this code to slack-sdk package.
+# Please maintain the code on your own if you copy this file.
+#
+# Also, please refer to the following gist for more discussion and better implementation:
+# https://gist.github.com/seratch/d81a445ef4467b16f047156bf859cda8
+#
+
+import logging
+from logging import Logger
+from typing import Optional
+from uuid import uuid4
+
+from google.cloud import datastore
+from google.cloud.datastore import Client, Entity, Query
+from slack_sdk.oauth import OAuthStateStore, InstallationStore
+from slack_sdk.oauth.installation_store import Installation, Bot
+
+
+class GoogleDatastoreInstallationStore(InstallationStore):
+    datastore_client: Client
+
+    def __init__(
+        self,
+        *,
+        datastore_client: Client,
+        logger: Logger,
+    ):
+        self.datastore_client = datastore_client
+        self._logger = logger
+
+    @property
+    def logger(self) -> Logger:
+        if self._logger is None:
+            self._logger = logging.getLogger(__name__)
+        return self._logger
+
+    def installation_key(
+        self,
+        *,
+        enterprise_id: Optional[str],
+        team_id: Optional[str],
+        user_id: Optional[str],
+        suffix: Optional[str] = None,
+        is_enterprise_install: Optional[bool] = None,
+    ):
+        enterprise_id = enterprise_id or "none"
+        team_id = "none" if is_enterprise_install else team_id or "none"
+        name = (
+            f"{enterprise_id}-{team_id}-{user_id}"
+            if user_id
+            else f"{enterprise_id}-{team_id}"
+        )
+        if suffix is not None:
+            name += "-" + suffix
+        return self.datastore_client.key("installations", name)
+
+    def bot_key(
+        self,
+        *,
+        enterprise_id: Optional[str],
+        team_id: Optional[str],
+        suffix: Optional[str] = None,
+        is_enterprise_install: Optional[bool] = None,
+    ):
+        enterprise_id = enterprise_id or "none"
+        team_id = "none" if is_enterprise_install else team_id or "none"
+        name = f"{enterprise_id}-{team_id}"
+        if suffix is not None:
+            name += "-" + suffix
+        return self.datastore_client.key("bots", name)
+
+    def save(self, i: Installation):
+        # the latest installation in the workspace
+        installation_entity: Entity = datastore.Entity(
+            key=self.installation_key(
+                enterprise_id=i.enterprise_id,
+                team_id=i.team_id,
+                user_id=None,  # user_id is removed
+                is_enterprise_install=i.is_enterprise_install,
+            )
+        )
+        installation_entity.update(**i.to_dict())
+        self.datastore_client.put(installation_entity)
+
+        # the latest installation associated with a user
+        user_entity: Entity = datastore.Entity(
+            key=self.installation_key(
+                enterprise_id=i.enterprise_id,
+                team_id=i.team_id,
+                user_id=i.user_id,
+                is_enterprise_install=i.is_enterprise_install,
+            )
+        )
+        user_entity.update(**i.to_dict())
+        self.datastore_client.put(user_entity)
+        # history data
+        user_entity.key = self.installation_key(
+            enterprise_id=i.enterprise_id,
+            team_id=i.team_id,
+            user_id=i.user_id,
+            is_enterprise_install=i.is_enterprise_install,
+            suffix=str(i.installed_at),
+        )
+        self.datastore_client.put(user_entity)
+
+        # the latest bot authorization in the workspace
+        bot = i.to_bot()
+        bot_entity: Entity = datastore.Entity(
+            key=self.bot_key(
+                enterprise_id=i.enterprise_id,
+                team_id=i.team_id,
+                is_enterprise_install=i.is_enterprise_install,
+            )
+        )
+        bot_entity.update(**bot.to_dict())
+        self.datastore_client.put(bot_entity)
+        # history data
+        bot_entity.key = self.bot_key(
+            enterprise_id=i.enterprise_id,
+            team_id=i.team_id,
+            is_enterprise_install=i.is_enterprise_install,
+            suffix=str(i.installed_at),
+        )
+        self.datastore_client.put(bot_entity)
+
+    def find_bot(
+        self,
+        *,
+        enterprise_id: Optional[str],
+        team_id: Optional[str],
+        is_enterprise_install: Optional[bool] = False,
+    ) -> Optional[Bot]:
+        entity: Entity = self.datastore_client.get(
+            self.bot_key(
+                enterprise_id=enterprise_id,
+                team_id=team_id,
+                is_enterprise_install=is_enterprise_install,
+            )
+        )
+        if entity is not None:
+            entity["installed_at"] = entity["installed_at"].timestamp()
+            return Bot(**entity)
+        return None
+
+    def find_installation(
+        self,
+        *,
+        enterprise_id: Optional[str],
+        team_id: Optional[str],
+        user_id: Optional[str] = None,
+        is_enterprise_install: Optional[bool] = False,
+    ) -> Optional[Installation]:
+        entity: Entity = self.datastore_client.get(
+            self.installation_key(
+                enterprise_id=enterprise_id,
+                team_id=team_id,
+                user_id=user_id,
+                is_enterprise_install=is_enterprise_install,
+            )
+        )
+        if entity is not None:
+            entity["installed_at"] = entity["installed_at"].timestamp()
+            return Installation(**entity)
+        return None
+
+    def delete_installation(
+        self,
+        enterprise_id: Optional[str],
+        team_id: Optional[str],
+        user_id: Optional[str],
+    ) -> None:
+        installation_key = self.installation_key(
+            enterprise_id=enterprise_id,
+            team_id=team_id,
+            user_id=user_id,
+        )
+        q: Query = self.datastore_client.query()
+        q.key_filter(installation_key, ">=")
+        for entity in q.fetch():
+            if entity.key.name.startswith(installation_key.name):
+                self.datastore_client.delete(entity.key)
+            else:
+                break
+
+    def delete_bot(
+        self,
+        enterprise_id: Optional[str],
+        team_id: Optional[str],
+    ) -> None:
+        bot_key = self.bot_key(
+            enterprise_id=enterprise_id,
+            team_id=team_id,
+        )
+        q: Query = self.datastore_client.query()
+        q.key_filter(bot_key, ">=")
+        for entity in q.fetch():
+            if entity.key.name.startswith(bot_key.name):
+                self.datastore_client.delete(entity.key)
+            else:
+                break
+
+    def delete_all(
+        self,
+        enterprise_id: Optional[str],
+        team_id: Optional[str],
+    ):
+        self.delete_bot(enterprise_id=enterprise_id, team_id=team_id)
+        self.delete_installation(
+            enterprise_id=enterprise_id, team_id=team_id, user_id=None
+        )
+
+
+class GoogleDatastoreOAuthStateStore(OAuthStateStore):
+    logger: Logger
+    datastore_client: Client
+    collection_id: str
+
+    def __init__(
+        self,
+        *,
+        datastore_client: Client,
+        logger: Logger,
+    ):
+        self.datastore_client = datastore_client
+        self._logger = logger
+        self.collection_id = "oauth_state_values"
+
+    @property
+    def logger(self) -> Logger:
+        if self._logger is None:
+            self._logger = logging.getLogger(__name__)
+        return self._logger
+
+    def consume(self, state: str) -> bool:
+        key = self.datastore_client.key(self.collection_id, state)
+        entity = self.datastore_client.get(key)
+        if entity is not None:
+            self.datastore_client.delete(key)
+            return True
+        return False
+
+    def issue(self, *args, **kwargs) -> str:
+        state_value = str(uuid4())
+        entity: Entity = datastore.Entity(
+            key=self.datastore_client.key(self.collection_id, state_value)
+        )
+        entity.update(value=state_value)
+        self.datastore_client.put(entity)
+        return state_value

examples/google_cloud_functions/handler.py

@@ -0,0 +1,66 @@
+# TODO: Once this once a new version newer than 1.13.2, delete this file
+
+from typing import Callable
+
+from flask import Request, Response, make_response
+
+from slack_bolt.app import App
+from slack_bolt.error import BoltError
+from slack_bolt.lazy_listener import LazyListenerRunner
+from slack_bolt.oauth import OAuthFlow
+from slack_bolt.request import BoltRequest
+from slack_bolt.response import BoltResponse
+
+
+def to_bolt_request(req: Request) -> BoltRequest:
+    return BoltRequest(  # type: ignore
+        body=req.get_data(as_text=True),
+        query=req.query_string.decode("utf-8"),
+        headers=req.headers,  # type: ignore
+    )  # type: ignore
+
+
+def to_flask_response(bolt_resp: BoltResponse) -> Response:
+    resp: Response = make_response(bolt_resp.body, bolt_resp.status)
+    for k, values in bolt_resp.headers.items():
+        if k.lower() == "content-type" and resp.headers.get("content-type") is not None:
+            # Remove the one set by Flask
+            resp.headers.pop("content-type")
+        for v in values:
+            resp.headers.add_header(k, v)
+    return resp
+
+
+class NoopLazyListenerRunner(LazyListenerRunner):
+    def start(self, function: Callable[..., None], request: BoltRequest) -> None:
+        raise BoltError(
+            "The google_cloud_functions adapter does not support lazy listeners. "
+            "Please consider either having a queue to pass the request to a different function or "
+            "rewriting your code not to use lazy listeners."
+        )
+
+
+class SlackRequestHandler:
+    def __init__(self, app: App):  # type: ignore
+        self.app = app
+        # Note that lazy listener is not supported
+        self.app.listener_runner.lazy_listener_runner = NoopLazyListenerRunner()
+        if self.app.oauth_flow is not None:
+            self.app.oauth_flow.settings.redirect_uri_page_renderer.install_path = "?"
+
+    def handle(self, req: Request) -> Response:
+        if req.method == "GET":
+            if self.app.oauth_flow is not None:
+                oauth_flow: OAuthFlow = self.app.oauth_flow
+                bolt_req = to_bolt_request(req)
+                if "code" in req.args or "error" in req.args or "state" in req.args:
+                    bolt_resp = oauth_flow.handle_callback(bolt_req)
+                    return to_flask_response(bolt_resp)
+                else:
+                    bolt_resp = oauth_flow.handle_installation(bolt_req)
+                    return to_flask_response(bolt_resp)
+        elif req.method == "POST":
+            bolt_resp: BoltResponse = self.app.dispatch(to_bolt_request(req))
+            return to_flask_response(bolt_resp)
+
+        return make_response("Not Found", 404)