MLB Gameday Bot ⚾

For demos of the bot's commands, view its github pages site here: https://alecm33.github.io/mlb-gameday-bot/

This bot and its author are not affiliated with the MLB. The bot uses the MLB Stats API, which is subject to the notice posted at http://gdx.mlb.com/components/copyright.txt

A Discord bot that integrates with the MLB Stats API to track your team of choice. For me, it's the Cleveland Guardians.

When running, the bot periodically polls for games in a 48-hour window centered on the current date. Whichever game is closest in time is considered the "current" game, and will be the game for which a lot of the commands returns data. If there's a doubleheader, the bot may ask you to specify which game. If a game is live, the bot subscribes to its MLB.com Gameday live feed, and in turn reports events to any number of subscribed Discord channels. Slash Commands include:

• /attendance - view the attendance for the current game.
• /batter - view stats on a specified batter. If you don't provide a name, the bot will check for a live game and use the current batter.
• /batter_savant - view Baseball Savant percentile rankings for a specified batter. If you don't provide a name, the bot will check for a live game and use the current batter.
• /box_score - view the box score for the current game, including hitting and pitching stats.
• /gameday_preference - change the preference for the gameday subscription. This includes which types of plays to report ("all plays" or "scoring plays only") and a reporting delay of 0-180 seconds.
• /highlights - get a direct link to the "game story", which is MLB's timeline of key moments.
• /lineup - view the lineup card for the current game.
• /line_score - view the line score for the current game.
• /pitcher - view stats on a specified pitcher. If you don't provide a name, the bot will check for a live game and use the current pitcher.
• /pitcher_savant - view Baseball Savant percentile rankings for a specified pitcher. If you don't provide a name, the bot will check for a live game and use the current pitcher.
• /schedule - view the upcoming schedule for the next week of games.
• /scoring_plays - get a curated list of scoring plays, with direct links to the play on the Gameday page.
• /standings - check the standings for your team's division.
• /starters - look at the starting pitching matchup for the current game. Includes portraits of both starters, their W/L, ERA, and WHIP, and a list of the pitches they throw.
• /subscribe_gameday - subscribe a given Discord channel to receive real-time updates from the "Gameday" feed. This command is restricted to certain roles. Users can adjust which plays the bot reports and customize a reporting delay. The message includes a description of the play, any change in score, and statcast metrics for balls in play.
• /unsubscribe_gameday - un-subscribe a given Discord channel from the above functionality.
• /weather - view the weather for current the game.
• /wildcard - the current wildcard standings.

...and likely more to follow!

Examples:

Tech Stack

Written in JavaScript using Discord.js. Running on the Heroku platform.

The bot uses a PostgreSQL database hosted for free on the Aiven Platform to keep track of the Discord channels that have subscribed to the real-time gameday feature.

I integrate with the MLB stats API for a dizzying amount of data. Its documentation is limited, but there is some. Shout out to Todd Roberts and his project for getting me acquainted with some of the subtleties: https://pypi.org/project/MLB-StatsAPI/. You can also view the spec for the MLB's "master game object", nicknamed GUMBO, here: https://bdata-research-blog-prod.s3.amazonaws.com/uploads/2019/03/GUMBOPDF3-29.pdf. I'm also happy to answer what I can about how to use the API.

Using my copy of the bot in your servers

My instance of the bot for the Cleveland Guardians is private. The bot is only designed to follow one team at a time. If you are interested in running this bot in your own server, feel free to reach out to me and I'd be happy to help get you started. Read below for an initial guide.

Running your own copy of the bot

This will assume you are somewhat familiar with Node.js and developing Discord bots.

Using Docker

Requires a machine with the Docker Desktop installed and the Docker Engine running.

1. Create a file called .env in the root directory, and populate it with the appropriate values. The .env.example file contains all the required variables with placeholder values. Each one is explained below.
   • DB_USER: the user for the postgres database
   • DB_PASSWORD: the password for the postgres database user
   • NODE_ENV: the node.js environment (production or development) in which to run the bot.
   • DB_NAME: the name for the postgres database
   • DB_PORT: the port for the postgres database
   • DISCORD_TOKEN: your discord bot's auth token (sensitive)
   • TEAM_ID: the id of the team you want the bot to follow. These match those of the "teams" resource in the MLB stats API: https://statsapi.mlb.com/api/v1/teams?sportId=1 . They are also stored statically in config/globals.js. Applicable commands will be configured for that team.
   • LOG_LEVEL: your chosen log level (info, error, warn, debug, or trace)
   • DISCORD_CLIENT_ID: the client ID of your Discord application
   • REQUIRE_SSL: whether the postgres database connection should require SSL.
   • TIME_ZONE: Your chosen time zone. Defaults to EST. Time zone names correspond to the Zone and Link names of the IANA Time Zone Database, such as "UTC", "Asia/Shanghai", "Asia/Kolkata", and "America/New_York". Additionally, time zones can be given as UTC offsets in the format "±hh:mm", "±hhmm", or "±hh", for example as "+01:00", "-2359", or "+23".
2. Run docker-compose up

Without Docker

1. Populate the following environment variables:

   • CLIENT_ID - your bot's client ID, AKA application ID.
   • DATABASE_STRING - a connection string for a PostgreSQL database instance. (sensitive). That database should have the schema contained here in the file database/schema.sql. If requiring SSL, you'll need to place your cert in database/certs.
   • LOG_LEVEL - your chosen log level.
   • TEAM_ID - the team you want to follow. These match those of the "teams" resource in the MLB stats API: https://statsapi.mlb.com/api/v1/teams?sportId=1 . They are also stored statically in config/globals.js. Every command will be configured for that team.
   • TOKEN - your bot's authentication token. (sensitive)
   • TIME_ZONE - Your chosen time zone. Defaults to EST. Time zone names correspond to the Zone and Link names of the IANA Time Zone Database, such as "UTC", "Asia/Shanghai", "Asia/Kolkata", and "America/New_York". Additionally, time zones can be given as UTC offsets in the format "±hh:mm", "±hhmm", or "±hh", for example as "+01:00", "-2359", or "+23".

2. run npm start

Optional - add emojis!

Discord allows applications to have up to 2,000 custom emojis. I have integrated team logo emojis into the app, to be used with commands such as /schedule:

On the page for your application in the Discord Dev Portal, there is a section for Emojis. There you can upload images. I recommend you use those I have stored here under /images/spots. Upload all 30, preserving the names. That should be all that's necessary to start seeing them show up - they will be fetched when the bot starts up.

If the bot starts up successfully, the start-up logs look something like the following (subject to your log level):

LOG    Mon, 17 Mar 2025 21:13:15 GMT :  Ready!
LOG    Mon, 17 Mar 2025 21:13:15 GMT :  bot successfully logged in
LOG    Mon, 17 Mar 2025 21:13:15 GMT :  Subscribed channels: []
LOG    Mon, 17 Mar 2025 21:13:15 GMT :  Games: polling...
DEBUG  Mon, 17 Mar 2025 21:13:15 GMT :  https://statsapi.mlb.com/api/v1/schedule?hydrate=team,lineups&sportId=1&startDate=2025-03-16&endDate=2025-03-18&teamId=114
LOG    Mon, 17 Mar 2025 21:13:15 GMT :  Fetched application emojis.
TRACE  Mon, 17 Mar 2025 21:13:15 GMT :  Current game PKs: [
  {
    "key": 779092,
    "date": "2025-03-16",
    "status": "F"
  },
  {
    "key": 778815,
    "date": "2025-03-17",
    "status": "P"
  },
  {
    "key": 778921,
    "date": "2025-03-18",
    "status": "S"
  }
]

Contributing

I welcome suggestions on new features or improvements. I also welcome proposals for collaboration. Just let me know.