PythonでSlackのメッセージを一括削除→Cloud Functionsで定期実行 全手順

$ vi delete_old_messages.py

import os, sys
import time
from slack_sdk import WebClient  # Slack APIへリクエストするためのクライアント。SDK使用。
from slack_sdk.errors import SlackApiError  # Slack APIエラーオブジェクト。SDK使用。


TERM = 60 * 60 * 24 * 7  # 秒で表した１週間


def delete_old_messages(channel_id):
    client = WebClient(
        token=os.environ["SLACK_API_TOKEN"]
    )  # WebClientインスタンス生成。引数は、Tokenコード。
    latest = int(time.time() - TERM)  # 現在日時 - １週間 の UNIX時間
    cursor = None  # シーク位置。最初は None ページを指定して、次からは next_cursor が指し示す位置。
    while True:
        try:
            response = client.conversations_history(  # conversations_history ＝ チャット一覧を得る
                channel=channel_id,
                latest=latest,
                cursor=cursor  # チャンネルID、latest、シーク位置を指定。
                # latestに指定した時間よりも古いメッセージが得られる。latestはUNIX時間で指定する。
            )
        except SlackApiError as e:
            sys.exit(
                e.response["error"]  # エラーが発生したら即終了
            )  # str like 'invalid_auth', 'channel_not_found'

        if "messages" in response:  # response["messages"]が有るか？
            for message in response["messages"]:  # response["messages"]が有る場合、１件ずつループ
                time.sleep(1)
                try:
                    client.chat_delete(
                        channel=channel_id, ts=message["ts"]
                    )  # chat_delete ＝ 指定したチャットを削除
                # 引数にチャンネルID、ts（タイムスタンプ：conversations_historyのレスポンスに含まれる）を指定して、削除
                except SlackApiError as e:
                    sys.exit(e.response["error"])  # エラーが発生したら即終了

        if "has_more" not in response or response["has_more"] is not True:
            # conversations_historyのレスポンスに["has_more"]が無かったり、has_moreの値がFalseだった場合、終了する。
            break

        if (
            "response_metadata" in response
            and "next_cursor" in response["response_metadata"]
        ):  # conversations_historyのレスポンスに["response_metadata"]["next_cursor"]が有る場合、cursorをセット
            # （上に戻って、もう一度、conversations_history取得）
            cursor = response["response_metadata"]["next_cursor"]
        else:
            break
        time.sleep(1)


if __name__ == "__main__":
    args = sys.argv
    if len(args) < 2:
        print("The first argument is required and must be a channel id.")
    else:
        delete_old_messages(args[1])  # Slackのチャンネルコードを引数に取る。（注意：チャンネル名ではない。）

#TERM = 60 * 60 * 24 * 7
TERM = 0

# pip3 install slack_sdk

# export SLACK_API_TOKEN='xoxp-0123456789012-0123456789012-0123456789012-1a2b3c5d6e7f8g9h1a2b3c5d6aaaaaab'

# python3 delete_old_messages.py C0123456789

slack_sdk.errors.SlackApiError: The request to the Slack API failed. (url: https://www.slack.com/api/conversations.info)
The server responded with: {'ok': False, 'error': 'channel_not_found'}

slack_sdk.errors.SlackApiError: The request to the Slack API failed. (url: https://www.slack.com/api/conversations.history)
The server responded with: {'ok': False, 'error': 'missing_scope', 'needed': 'channels:history,groups:history,mpim:history,im:history', 'provided': 'chat:write,channels:read,groups:read,mpim:read,im:read'}

# python3 delete_old_messages.py
/usr/local/lib/python3.7/dist-packages/slack/deprecation.py:16: UserWarning: slack package is deprecated. Please use slack_sdk.web/webhook/rtm package instead. For more info, go to https://slack.dev/python-slack-sdk/v3-migration/
  warnings.warn(message)
Traceback (most recent call last):
  File "delete_old_messages.py", line 4, in <module>
    from slack.errors import SlackApiError
  File "/usr/local/lib/python3.7/dist-packages/slack/__init__.py", line 7, in <module>
    from slack_sdk.rtm import RTMClient  # noqa
  File "/usr/local/lib/python3.7/dist-packages/slack_sdk/rtm/__init__.py", line 16, in <module>
    import aiohttp
ModuleNotFoundError: No module named 'aiohttp'

# pip3 install aiohttp

from slack.errors import SlackApiError

from slack_sdk.errors import SlackApiError

import os, sys
import time
from slack_sdk import WebClient
from slack_sdk.errors import SlackApiError


TERM = 60 * 60 * 24 * 7


def delete_old_messages(event, context):
    client = WebClient(token=os.environ["SLACK_API_TOKEN"])
    channel_id = os.environ["channel_id"]
    latest = int(time.time() - TERM)
    cursor = None
    while True:
        try:
            response = client.conversations_history(
                channel=channel_id, latest=latest, cursor=cursor
            )
        except SlackApiError as e:
            sys.exit(
                e.response["error"]
            )  # str like 'invalid_auth', 'channel_not_found'

        if "messages" in response:
            for message in response["messages"]:
                time.sleep(1)
                try:
                    client.chat_delete(channel=channel_id, ts=message["ts"])
                except SlackApiError as e:
                    sys.exit(e.response["error"])

        if "has_more" not in response or response["has_more"] is not True:
            break

        if (
            "response_metadata" in response
            and "next_cursor" in response["response_metadata"]
        ):
            cursor = response["response_metadata"]["next_cursor"]
        else:
            break
        time.sleep(1)
    print("OK")

# pip3 install functions-framework

# vi main.py

import os, sys
import time
from slack_sdk import WebClient
from slack_sdk.errors import SlackApiError


TERM = 60 * 60 * 24 * 7


def delete_old_messages(event, context):
    client = WebClient(token=os.environ["SLACK_API_TOKEN"])
    channel_id = os.environ["channel_id"]
    latest = int(time.time() - TERM)
    cursor = None
    while True:
        try:
            response = client.conversations_history(
                channel=channel_id, latest=latest, cursor=cursor
            )
        except SlackApiError as e:
            sys.exit(
                e.response["error"]
            )  # str like 'invalid_auth', 'channel_not_found'

        if "messages" in response:
            for message in response["messages"]:
                time.sleep(1)
                try:
                    client.chat_delete(channel=channel_id, ts=message["ts"])
                except SlackApiError as e:
                    sys.exit(e.response["error"])

        if "has_more" not in response or response["has_more"] is not True:
            break

        if (
            "response_metadata" in response
            and "next_cursor" in response["response_metadata"]
        ):
            cursor = response["response_metadata"]["next_cursor"]
        else:
            break
        time.sleep(1)
    print("OK")

# export channel_id='C0123456789'
# export SLACK_API_TOKEN='xoxp-0123456789012-0123456789012-0123456789012-1a2b3c5d6e7f8g9h1a2b3c5d6aaaaaab'
# functions-framework --target delete_old_messages --signature-type=event

$ curl -d '{"data": {}}' -X POST -H "Content-Type: application/json" http://localhost:8080