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Application: seal

Slack bot that publishes a team’s pull requests to their Slack channel



Build Status

What is it?

This is a Slack bot that publishes a team’s pull requests to their Slack Channel, once provided the organisation name and the team members’ github names. It is my first 20% project at GDS.

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How to use it?


Fork the repo and add/change the config files that relate to your github organisation. For example, the alphagov config file is located at config/alphagov.yml and the config for scheduled daily visits can be found in bin

Include your team’s name, the Github names of your team members, and the Slack channel you want to post to.

In your shell profile, put in:

export SEAL_ORGANISATION="your_github_organisation"
export GITHUB_TOKEN="get_your_github_token_from_yourgithub_settings"
export SLACK_WEBHOOK="get_your_incoming_webhook_link_for_your_slack_group_channel"
export GITHUB_API_ENDPOINT="your_github_api_endpoint" # OPTIONAL If you are using a Github Enterprise instance

Env variables

Another option, which is 12-factor-app ready is to use ENV variables for basically everything. In that case you don’t need a config file at all.

Divider is ‘,’ (comma) symbol.

In your shell profile, put in:

export SEAL_ORGANISATION="your_github_organisation"
export GITHUB_TOKEN="get_your_github_token_from_yourgithub_settings"
export GITHUB_API_ENDPOINT="your_github_api_endpoint" # OPTIONAL If you are using a Github Enterprise instance
export SLACK_WEBHOOK="get_your_incoming_webhook_link_for_your_slack_group_channel"
export SLACK_CHANNEL="#whatever-channel-you-prefer"
export GITHUB_MEMBERS="netflash,binaryberry,otheruser"
export GITHUB_EXCLUDE_LABELS="[DO NOT MERGE],Don't merge,DO NOT MERGE,Waiting on factcheck,wip"
export GITHUB_EXCLUDE_REPOS="notmyproject,someotherproject" # Ensure these projects are *NOT* included
export GITHUB_INCLUDE_REPOS="definitelymyproject,forsuremyproject" # Ensure *only* these projects will be included
export COMPACT=true # Use a more compact version of the seal output
export SEAL_QUOTES="Everyone should have the opportunity to learn. Don’t be afraid to pick up stories on things you don’t understand and ask for help with them.,Try to pair when possible."

Bash scripts

In your forked repo, include your team names in the appropriate bash script. Ex. bin/

Local testing

To test the script locally, go to Slack and create a channel or private group called “#angry-seal-bot-test” (the Slack webhook you set up should have its channel set to “#angry-seal-bot-test” in the Integration Settings). Then run ./bin/seal.rb your_team_name in your command line, and you should see the post in the #angry-seal-bot-test channel.

If you don’t want to post github pull requests but a random quote from your team’s quotes config, run ./bin/seal.rb your_team_name quotes

Slack configuration

You should also set up the following custom emojis in Slack:

  • :informative_seal:
  • :angrier_seal:
  • :seal_of_approval:
  • :happyseal:
  • :halloween_informative_seal:
  • :halloween_angrier_seal:
  • :halloween_seal_of_approval:
  • :festive_season_informative_seal:
  • :festive_season_angrier_seal:
  • :festive_season_seal_of_approval:
  • :manatea:

You can use the images in images/emojis that have the corresponding names.

When that works, you can push the app to Heroku and add the GITHUB_TOKEN and SLACK_WEBHOOK environment variables to heroku.

Use the Heroku scheduler add-on to create repeated tasks - I set the seal to run at 9.30am every morning (the seal won’t post on weekends). The scheduler is at and the command to run is bin/seal.rb your_team_name

Any questions feel free to contact me on Twitter - my handle is binaryberry

Deploy to Heroku


How to run the tests?

Just run rspec in the command line

Docker container

You can build your own docker container, Dockerfile is provided.

docker build -t seal .

And then run it (assuming you already set all the env variables)

docker run -it --rm --name seal \
  -e DYNO=${DYNO} \

Diary of how this app was built

10th April:

  • Finalised what the app does:

    • Checks if any pull requests are over 2 days old (angry seal)
    • at 9.45am prepares an overview of all pull requests that need reviewing (informative seal)
    • when a team member posts a new pull request, publishes it on slack (notification seal) (this feature was then abandoned, as I thought it’s best for this not to be automated, it’s more motivating when real people ask for a review, not a bot)

  • Researched what technologies and gems I could use and what the app structure would be like

  • Started the Rails app

17th April:

  • researched github_api

24th April:

  • got github_api working, first test with dummy data passing

1st of May

  • got github_listener to take into account organisations

8th of May:

  • tried stubbing Github API

15th of May:

21st of May:

  • Building Sinatra app for stubbing
  • Attempts to filter the 3,400 repo list by date the repo was modified - tests (and app) are still very slow

28th of May:

  • Due to new team structure that assigns a list of repos to each team, decided the manually enter the list of repos that belong to a team instead of scanning through all of them. That should sort the speed problem, the stubbing problem, a lot of things.
  • moved to a non-Rails app to make it lighter
  • got Github to list repos; works for my personal pull requests, but doesn’t work with the GOV.UK stuff yet, need to figure out why

5th of June:

  • Github fetcher class now works with organisations, hence GOV.UK stuff

11th of June:

  • Stubbed Github API

12th of June:

  • Github Fetcher now also returns the link to the pull request
  • Started Slackbot poster class, it can post to Slack
  • Started Message builder class, not finished

13th of June:

  • finished Slackbot poster class
  • finished Message builder class
  • added name of repo to info sent by GithubFetcher
  • added options to the Slackbot poster class so each post comes from informative seal
  • Works locally in test room. YEAY!

17th of June:

  • refactoring of Github fetcher
  • pushed to Heroku

18th of June:

  • started Heroku scheduler and launched on core-formats team room!

22nd of June

  • Ensure Angry seal doesn’t get triggered at the weekend

26th of June:

  • launched on finding-stuff team
  • investigated adding comments

3rd of July:

  • launched on custom team
  • added comments
  • investigating angry seal - stuck by a strange syntax error line 34 when trying to run the script

10th of July

  • Extracted config information to yaml files
  • fixed informative seal - mood_hash was causing issues

17th of July

  • Angry Seal!

21st of July

  • fix API stubbing

22nd of July

  • Add age of pull requests

24th of July

  • Optionally display labels for a pull request, if they exist (use_labels config option)
  • Optionally hide pull requests with certain labels (exclude_labels config list)
  • Optionally hide pull requests with certain phrases in the title (exclude_titles config list)

19th of August

  • Seal will bark at all teams in the config if no team is specified as an argument to ./bin/{angry,informative}_seal.rb, making Heroku scheduling easier.

4th of September

  • Seal now displays thumbs up when present in comments
  • Angry seal now looks angrier

13th of September

  • Seal now has only one script to be triggered - will start either the angry seal, the informative seal or the seal of approval each day.

6th of January

  • Seal can now post random quotes from the team’s list of quotes in the config. Can be used as a reminder or for inspirational quotes!


How to list your organisation’s repositories modified within the last year:

In irb, from the folder of the project, run:

require 'octokit'
github = => ENV['GITHUB_TOKEN'], auto_pagination: true)
response = github.repos(org: ENV['SEAL_ORGANISATION'])
repo_names = { |repo| Date.parse(repo.updated_at.to_s) > ( - 365) }.map(&:name)


Github fetcher:

  • queries Github’s API

Message Builder:

  • produces message from Github API’s content

Slack Poster:

  • posts message to Slack

Trello board:


See the LICENSE file for license rights and limitations (MIT).