from urllib.parse import parse_qs
-from turbot.rot import rot
+from slack import WebClient
+import boto3
+import requests
+import json
+import os
-def turbot_lambda(event, context):
- """Top-level entry point for our lambda function.
+import turbot.actions
+import turbot.commands
+import turbot.events
+import turbot.views
- This parses the request and arguments and farms out to supporting
- functions to implement all supported slash commands."""
+ssm = boto3.client('ssm')
- body = parse_qs(event['body'])
- command = body['command'][0]
- args = body['text'][0]
+response = ssm.get_parameter(Name='SLACK_SIGNING_SECRET', WithDecryption=True)
+slack_signing_secret = response['Parameter']['Value']
+os.environ['SLACK_SIGNING_SECRET'] = slack_signing_secret
+
+# Note: Late import here to have the environment variable above available
+from turbot.slack import slack_is_valid_request # noqa
- if (command == "/rotlambda" or command == "/rot"):
- return rot_slash_command(args)
+response = ssm.get_parameter(Name='SLACK_BOT_TOKEN', WithDecryption=True)
+slack_bot_token = response['Parameter']['Value']
+slack_client = WebClient(slack_bot_token)
- error = "Command {} not implemented.".format(command)
+def error(message):
+ """Generate an error response for a Slack request
- print("Error: {}".format(error))
+ This will print the error message (so that it appears in CloudWatch
+ logs) and will then return a dictionary suitable for returning
+ as an error response."""
+
+ print("Error: {}.".format(message))
return {
- 'statusCode': 404,
- 'body': error
+ 'statusCode': 400,
+ 'body': ''
}
-def rot_slash_command(args):
- """Implementation of the /rot command
+def turbot_lambda(event, context):
+ """Top-level entry point for our lambda function.
+
+ This function first verifies that the request actually came from
+ Slack, (by means of the SLACK_SIGNING_SECRET SSM parameter), and
+ refuses to do anything if not.
+
+ Then this defers to either turbot_event_handler or
+ turbot_slash_command to do any real work.
+ """
- The args string should be as follows:
+ headers = requests.structures.CaseInsensitiveDict(event['headers'])
- [count|*] String to be rotated
+ signature = headers['X-Slack-Signature']
+ timestamp = headers['X-Slack-Request-Timestamp']
- That is, the first word of the string is an optional number (or
- the character '*'). If this is a number it indicates an amount to
- rotate each character in the string. If the count is '*' or is not
- present, then the string will be rotated through all possible 25
- values.
+ if not slack_is_valid_request(signature, timestamp, event['body']):
+ return error("Invalid Slack signature")
- The result of the rotation is returned (with Slack formatting) in
- the body of the response so that Slack will provide it as a reply
- to the user who submitted the slash command."""
+ # It's a bit cheesy, but we'll just use the content-type header to
+ # determine if we're being called from a Slack event or from a
+ # slash command or other interactivity. (The more typical way to
+ # do this would be to have different URLs for each Slack entry
+ # point, but it's simpler to have our Slack app implemented as a
+ # single AWS Lambda, (which can only have a single entry point).
+ content_type = headers['content-type']
+
+ if (content_type == "application/json"):
+ return turbot_event_handler(event, context)
+ if (content_type == "application/x-www-form-urlencoded"):
+ return turbot_interactive_or_slash_command(event, context)
+ return error("Unknown content-type: {}".format(content_type))
+
+def turbot_event_handler(event, context):
+ """Handler for all subscribed Slack events"""
+
+ body = json.loads(event['body'])
+
+ type = body['type']
+
+ if type == 'url_verification':
+ return url_verification_handler(body)
+ if type == 'event_callback':
+ return event_callback_handler(body)
+ return error("Unknown event type: {}".format(type))
+
+def url_verification_handler(body):
+
+ # First, we have to properly respond to url_verification
+ # challenges or else Slack won't let us configure our URL as an
+ # event handler.
+ challenge = body['challenge']
return {
'statusCode': 200,
- 'body': rot(args)
+ 'body': challenge
}
+
+def event_callback_handler(body):
+ type = body['event']['type']
+
+ if type in turbot.events.events:
+ return turbot.events.events[type](slack_client, body)
+ return error("Unknown event type: {}".format(type))
+
+def turbot_interactive_or_slash_command(event, context):
+ """Handler for Slack interactive things (buttons, shortcuts, etc.)
+ as well as slash commands.
+
+ This function simply makes a quiuck determination of what we're looking
+ at and then defers to either turbot_interactive or turbot_slash_command."""
+
+ # Both interactives and slash commands have a urlencoded body
+ body = parse_qs(event['body'])
+
+ # The difference is that an interactive thingy has a 'payload'
+ # while a slash command has a 'command'
+ if 'payload' in body:
+ return turbot_interactive(json.loads(body['payload'][0]))
+ if 'command' in body:
+ return turbot_slash_command(body)
+ return error("Unrecognized event (neither interactive nor slash command)")
+
+def turbot_interactive(payload):
+ """Handler for Slack interactive requests
+
+ These are the things that come from a user interacting with a button
+ a shortcut or some other interactive element that our app has made
+ available to the user."""
+
+ type = payload['type']
+
+ if type == 'block_actions':
+ return turbot_block_action(payload)
+ return error("Unrecognized interactive type: {}".format(type))
+
+def turbot_block_action(payload):
+ """Handler for Slack interactive block actions
+
+ Specifically, those that have a payload type of 'block_actions'"""
+
+ actions = payload['actions']
+
+ if len(actions) != 1:
+ return error("No support for multiple actions ({}) in a single request"
+ .format(len(actions)))
+
+ action = actions[0]
+
+ atype = action['type']
+ avalue = action['value']
+
+ if (
+ atype in turbot.actions.actions
+ and avalue in turbot.actions.actions[atype]
+ ):
+ return turbot.actions.actions[atype][avalue](payload)
+ return error("Unknown action of type/value: {}/{}".format(atype, avalue))
+
+def turbot_slash_command(body):
+ """Implementation for Slack slash commands.
+
+ This parses the request and arguments and farms out to
+ supporting functions to implement all supported slash commands.
+ """
+
+ command = body['command'][0]
+ args = body['text'][0]
+
+ if command in turbot.commands.commands:
+ return turbot.commands.commands[command](slack_client, body, args)
+
+ return error("Command {} not implemented".format(command))
projects / turbot / blobdiff