Listening & responding to actions

Your app can listen and respond to user actions, like button clicks, and menu selects, using the action method.

Listening to actions

Actions can be filtered on an action_id parameter of type str or re.Pattern. The action_id parameter acts as a unique identifier for interactive components on the Slack platform.

You'll notice in all action() examples, ack() is used. It is required to call the ack() function within an action listener to acknowledge that the request was received from Slack. This is discussed in the acknowledging requests guide.

Refer to the module document to learn the available listener arguments.

# Your listener will be called every time a block element with the action_id "approve_button" is triggered
@app.action("approve_button")
def update_message(ack):
    ack()
    # Update the message to reflect the action

Listening to actions using a constraint object

You can use a constraints object to listen to block_ids and action_ids (or any combination of them). Constraints in the object can be of type str or re.Pattern.

# Your function will only be called when the action_id matches 'select_user' AND the block_id matches 'assign_ticket'
@app.action({
    "block_id": "assign_ticket",
    "action_id": "select_user"
})
def update_message(ack, body, client):
    ack()

    if "container" in body and "message_ts" in body["container"]:
        client.reactions_add(
            name="white_check_mark",
            channel=body["channel"]["id"],
            timestamp=body["container"]["message_ts"],
        )

Responding to actions

There are two main ways to respond to actions. The first (and most common) way is to use say(), which sends a message back to the conversation where the incoming request took place.

The second way to respond to actions is using respond(), which is a utility to use the response_url associated with the action.

Refer to the module document to learn the available listener arguments.

# Your listener will be called every time an interactive component with the action_id “approve_button” is triggered
@app.action("approve_button")
def approve_request(ack, say):
    # Acknowledge action request
    ack()
    say("Request approved 👍")

Using respond() method

Since respond() is a utility for calling the response_url, it behaves in the same way. You can pass all the message payload properties as keyword arguments along with optional properties like response_type (which has a value of "in_channel" or "ephemeral"), replace_original, delete_original, unfurl_links, and unfurl_media. With that, your app can send a new message payload that will be published back to the source of the original interaction.

# Listens to actions triggered with action_id of “user_select”
@app.action("user_select")
def select_user(ack, action, respond):
    ack()
    respond(f"You selected <@{action['selected_user']}>")