Simple Python Slackbot does not listen or respond to channel

Question

I am getting started with the Slack API, so i just wanted to write a bot that listens into a channel and whenever someone says a keyword, it responds with an answer. In this case, if someone says 'hello' it responds with 'world'.

Here is what I have done so far. I registered for a Slack account. I registered a a new bot at https://slack.com/apps/build >> Make a Custom Integration >> Something just for my team, gave it a name etc.

Then i created a virtualenv and then wrote this script:

import time
from slackclient import SlackClient

BOT_TOKEN = "I PUT MY TOKEN HERE THAT I GOT FROM REGISTRATION"
CHANNEL_NAME = "general"

def main():
    # Create the slackclient instance
    sc = SlackClient(BOT_TOKEN)

    # Connect to slack
    if sc.rtm_connect():
        # Send first message
        sc.rtm_send_message(CHANNEL_NAME, "I'm the Hello World Bot")

        while True:
            # Read latest messages
            for slack_message in sc.rtm_read():
                message = slack_message.get("text")
                user = slack_message.get("user")
                if not message or not user:
                    continue
                if "hello" in message:
                    sc.rtm_send_message(CHANNEL_NAME, "world")
    else:
        print("Couldn't connect to slack")

if __name__ == '__main__':
    main()

When i run it, my command prompt is just blinking, nothing happens, not even the intro message in the channel. So I have a few questions:

1) What is wrong, if anything, with my script?

2) In my Slack, I can see the bot's name in the Direct Messages list, but when i go to the #general channel, I only have one user, me, and the bot is not there. How do i add it there? When i click invite, it wants me to add people by email.

3) If I wanted it to listen to multiple channels, what would I have to change in the script?

Answer 1

As @smarx said, you definitely need to invite your bot to the channel. And then I use the chat.postMessage method to do a call and response:

 if re.search("hello", message):
     self.client.api_call("chat.postMessage", as_user="true",
                          channel=CHANNEL_NAME, text="world")

I also have a pause in my script, so try something closer to:

while True:
    for slack_message in sc.rtm_read():
            message = slack_message.get("text")
            user = slack_message.get("user")
            room = slack_message.get("channel")
               if re.search("hello", message):
                    self.client.api_call("chat.postMessage", as_user="true",
                                         channel=CHANNEL_NAME, text="world")
    time.sleep(0.25)