Blood bot

The blood bot posts an announcement to Discord or Telegram channels (or both) when teams land an early solve on a challenge.

Configuration#

bloodBot:
  bloodsCount: 3
  destinations:
    - provider:
        name: messages/discord
        options:
          url: https://discord.com/api/webhooks/123456/abcdef
    - provider:
        name: messages/telegram
        options:
          botToken: '123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11'
          chatId: '-1001234567890'

Field	Type	Default	Description
`bloodsCount`	`number`	`1`	Number of blood tiers to announce (1-3)
`destinations`	`array`	-	At least one destination required

bloodsCount set to 3 announces first, second, and third blood. Set it to 1 and only first blood gets announced.

Message providers#

Posts announcements through a Discord webhook.

Option	Description
`url`	Discord webhook URL

To create a webhook, navigate to Server Settings > Integrations > Webhooks > New Webhook, then copy the webhook URL.

Posts announcements through a Telegram bot.

Option	Description
`botToken`	Telegram bot token (from @BotFather)
`chatId`	Target chat or group ID
`threadId`	Message thread ID for forum/topic channels (optional)

Custom message templates#

Each destination can have a custom messageTemplate:

bloodBot:
  bloodsCount: 1
  destinations:
    - provider:
        name: messages/discord
        options:
          url: https://discord.com/api/webhooks/...
      messageTemplate: '{{teamName}} got {{bloodNumSentence}} blood on {{challengeCategory}}/{{challengeName}}!'

Template variables#

Variable	Description	Example
`{{teamName}}`	Team display name	`SuperHackers`
`{{teamUrl}}`	URL to team profile	`https://ctf.example.com/users/abc123`
`{{bloodNumSentence}}`	Blood ordinal	`first`, `second`, `third`
`{{challengeCategory}}`	Challenge category	`web`
`{{challengeName}}`	Challenge name	`SQL Injection 101`

Default templates#

When no custom template is set, the defaults kick in.

The Discord default is Congratulations to [`{{teamName}}`]({{teamUrl}}) for {{bloodNumSentence}} blood on `{{challengeCategory}}/{{challengeName}}`!.

The Telegram default is Congratulations to [*{{teamName}}*]({{teamUrl}}) for {{bloodNumSentence}} blood on `{{challengeCategory}}/{{challengeName}}`\!.

The Telegram template uses MarkdownV2 syntax and escapes the ! character, which the Telegram API requires.