'startConversation()' fails in a 'hears()' closure, triggered from a Slack Command

[th3d0g]

• BotMan Version: 2.0
• PHP Version: 7.1.9
• Messaging Service(s): Slack Driver 2.1
• Cache Driver: Botman Studio

Description:

Calling 'startConversation()' fails when called from the 'hears()' closure. See example below:

$botman->hears('/project', function ($bot) { $bot->startConversation(new ExampleConversation()); });

This is being triggered from a Slack command, which responds with:

/project failed with the error "invalid_attachments_format"

It's worth noting that the example included works which calls a controller function. This works differently as it's triggered via an Event as opposed to a Command in the example above.

$botman->hears('Start conversation', BotManController::class.'@startConversation');

Steps To Reproduce:

1. Setup a Slack bot, and add a command.

2. Create a 'hear()' function to listen out for this command. Within the closure run $bot->startConversation(new ExampleConversation());.

3. Call the command from Slack.

[christophrumpel]

What is the error you get?