Flack

Integrate slack commands and actions with flask

Setup

Either initialize the app immediately:

from flack import Flack
flack = Flack(app)

Or use a deferred initialization:

from flack import Flack
flack = Flack()

def get_app():
    # Create your flask application.
    flack.init_app(app)

Configuration

• FLACK_TOKEN Must match the secret generated by Slack when creation your app or integration, will be verified for every request.
• FLACK_URL_PREFIX URL namespace for the built-in api endpoints.
• FLACK_DEFAULT_NAME Used for any response whera as_user is not explicitly set.

Slack event handlers

Triggers

API Endpoint: /webhook

The most basic type of interations, webhooks invoked by trigger words in a channel.

@flack.trigger("!heart", as_user="Cupid")
def heart(text, user):
    return "{} :heart: {}".format(user.name, text)

Provides:

• text Any message after (but not including) the trigger word, may be an empty string.
• user The calling user, see: flack.CALLER.

Commmand

API Endpoint: /command

Slash-commands, may respond to the user privately or interact with the channel in which it was executed.

@flack.command("/weather")
def weather(text, user, channel):
    return "The weather in {} is currently: {}".format(text, get_weather(text))

Provides:

• text Any message after the trigger word, may be an empty string.
• user The calling user, see: flack.CALLER.
• channel The active channel or conversation, see: flack.CHANNEL.

Action

API Endpoint: /action

Action buttons included in advanced messages (see: flack.message.Action).

@flack.action("remind")
def remind(value, ts, instance, user, channel):
    remind_user(user)

Provides:

• value Generally the same as the action name.
• ts: The timestamp of the originating message, used for modifying it through the API.
• callback: The Callback ID of the originating message attachment, see: flack.message.Attachment
• user The interacting user, see: flack.CALLER.
• channel The originating channel, see: flack.CHANNEL.

Responding

TODO: Document flack.message objects

OAuth

While not necessary for basic usage, Flack has support for registering an OAuth application.

Configuration

• FLACK_CLIENT_ID Provided by Slack when creating an app.
• FLACK_CLIENT_SECRET Provided by Slack when creating an app.
• FLACK_SCOPE Slack API scope to request (default is commands,users:read,channels:read,chat:write:bot).

Usage

Generate the Slack button HTML snippet and expose it to the client wherever you like with flack.oauth.render_button()

Then create a view that can receive the generated credentials from Slack. Make sure the url matches what you provided as the "Redirect URL" when creating the Slack app.

import flack.oauth

@app.route('/callback')
@flack.oauth.callback
def callback(credentials):
    # Make sure to store the credentials somewhere safe.
    your_datastore.write({
        "team": credentials.team_id,
        "token": credentials.access_token,
        "scope": credentials.scope
    })
    # And make sure to inform the client everything went fine
    return "It worked!"

The credentials object is a namedtuple containing team_id, access_token, and scope.