v2

GCP Serverless Slackbot Template - version 2

Minimalistic code to create a serverless slash handler for a Slack bot. Further information on this repository can be found in the article Google Cloud Platform - Serverless Slack Bot. This version more gracefully handles cold starts to provide a more consistent acknowledgement response to Slack within the expected timeframs.

Deploy

Both the go and python cloud functions need to be deployed to create the slash command handler.

Python deployment:

gcloud functions deploy hello_bot --runtime python37 --trigger-http

The python function permissions need to grant the <project_id>@appspot.gserviceaccount.com user the Cloud Functions Invoker role. This makes the function available to be invoked from another Cloud function.

go deployment:

gcloud functions deploy Gobotween --runtime go111 --trigger-http

The go function permissions will need to be updated to grant allUsers the Cloud Functions Invoker role. This makes the function publicly available to be invoked from Slack.

Directory contents - go

config.json

Configuration information used at runtime. Update the SLACK_TOKEN and WEBHOOK_URL here for your environment/project. Use the endpoint URL for the python Cloud Function to update the value for SLASH_HANDLER.

gobotween.go

Main go code. Entry point is:

func Gobotween(w http.ResponseWriter, r *http.Request) {

Execution is then:

• return a HTTP 200 response
• load config if null (for a cold start)
• validate request and signature
• create POST request and forward to SLASH_HANDLER

Directory contents - python

main.py

python implementation of request handling for a slash command.

The entry point is:

def hello_bot(request):

Execution then consists of:

• validate the request
• execute the request or return an error message