slack_index.rb

#
# ENV["ESA_POST_NUMBER"]: 更新するesa記事の番号.
# ENV["SLACK_OAUTH_ACCESS_TOKEN"]: SlackのAccessToken. `channels:read` 権限が必要.
# ENV['ESA_API_TOKEN']: esaのtoken. write権限が必要.
# ENV['ESA_TEAM']: esaのteam名.
# ENV['SLACK_TEAM_NAME']: https://TEAM_NAME.slack.com の TEAM_NAME部分
#

require 'slack-ruby-client'
require 'esa'

# 全チャンネルを取得する
Slack.configure do |config|
  config.token = ENV["SLACK_OAUTH_ACCESS_TOKEN"]
end
slack_client = Slack::Web::Client.new
all_channels = []
slack_client.conversations_list(exclude_archived: true, limit: 1000, sleep_interval: 1, max_retries: 20) do |response|
  all_channels.concat(response.channels)
end

# esa用に加工
markdown_text_buffer = []
markdown_text_buffer << <<-EOS
# 概要
このesaは、 `#{ENV['SLACK_TEAM_NAME']}.slack.com` のパブリックチャンネル一覧です。

:chart_with_upwards_trend: **現在のチャンネル数：#{all_channels.length}**

# 一覧
EOS

all_channels.sort_by(&:name).each do |c|
  id = c.id
  url = "https://#{ENV['SLACK_TEAM_NAME']}.slack.com/archives/#{id}"
  name = c.name
  purpose = c.purpose.value
  topic = c.topic.value
  num_members = c.num_members

  markdown_text_buffer << <<-EOS
## [##{name}](#{url})｜:busts_in_silhouette: #{num_members}

#### 目的
```
#{purpose}
```

#### トピック
```
#{topic}
```
  EOS
end
md_text = markdown_text_buffer.join("\n")

# esaに書き込む
esa_client = Esa::Client.new(access_token: ENV['ESA_API_TOKEN'], current_team: ENV['ESA_TEAM'])
esa_client.update_post(
  ENV["ESA_POST_NUMBER"],
  wip: false,
  updated_by: 'esa_bot', # owner権限がないとesa_botは指定できません ref.https://docs.esa.io/posts/102#PATCH%20/v1/teams/:team_name/posts/:post_number
  message: '[skip notice]',
  body_md: md_text
)