From: Carl Worth <cworth@cworth.org>
Date: Thu, 22 Oct 2020 07:50:09 +0000 (-0700)
Subject: Defer all sheet creation until after the channel is created
X-Git-Url: https://git.cworth.org/git?a=commitdiff_plain;h=b9fc94a0e63e3eea4e06b869d7c771357714178c;hp=9b570c69c799bc2442d712507474c803f7a571bf;p=turbot

Defer all sheet creation until after the channel is created

Specifically, we no longer attempt to do sheet creation in the handler
for the interaction of the user submitting a modal dialog. The reason
that was a a bad idea is that the sheet creation can take several
seconds, (including time to copy data from a template sheet, etc.),
while Slack will timeout after merely 3 seconds of a user submission
and report an error.

This way, we can promptly validate the user's input (giving them a
clean error on the form if necessary), then simply create the channel
in the handler and primomptly return (so Slack doesn't timeout).

Then, separately, we now have a listener setup for the channel_created
event and in _that_ handler we do all the sheet creation necessary. We
have all the time we want here since channel_created is just an event
without a user waiting for a response, so Slack doesn't impose a
3-second timeout on us.
---

diff --git a/turbot/events.py b/turbot/events.py
index 32d061a..26c8945 100644
--- a/turbot/events.py
+++ b/turbot/events.py
@@ -1,6 +1,15 @@
 from turbot.blocks import (
     section_block, text_block, button_block, actions_block
 )
+import turbot.sheets
+import turbot.slack
+
+TURBOT_USER_ID = 'U01B9QM4P9R'
+
+events = {}
+
+lambda_success = {'statusCode': 200}
+lambda_error = {'statusCode': 400}
 
 def hunt_block(hunt):
     name = hunt['name']
@@ -15,10 +24,9 @@ def hunt_block(hunt):
 
     return section_block(text_block(text))
 
-def home(turb, user_id, body):
+def home(turb, user_id):
     """Returns a view to be published as the turbot home tab for user_id
 
-    The body argument is a dictionary as provided by the Slack request.
     The return value is a dictionary suitable to be published to the
     Slack views_publish API."""
 
@@ -38,12 +46,198 @@ def home(turb, user_id, body):
         ]
     }
 
-def app_home_opened(turb, body):
-    user_id = body['event']['user']
-    view = home(turb, user_id, body)
+def app_home_opened(turb, event):
+    """Handler for the app_home_opened event
+
+    This event occurs when a user visits the home tab for the turbot app.
+    In response to this event we need to publish a view for the user."""
+
+    user_id = event['user']
+    view = home(turb, user_id)
     turb.slack_client.views_publish(user_id=user_id, view=view)
-    return "OK"
+    return lambda_success
+
+events['app_home_opened'] = app_home_opened
+
+def hunt_channel_created(turb, channel_name, channel_id):
+    """Creates sheet and a DynamoDB table for a newly-created hunt channel"""
+
+    # First see if we can find an entry for this hunt in the database.
+    # If not, simply return an error and let Slack retry
+    hunts_table = turb.db.Table("hunts")
+    response = hunts_table.get_item(
+        Key={'channel_id': channel_id},
+        ConsistentRead=True
+    )
+    if 'Item' not in response:
+        print("Warning: Cannot find channel_id {} in hunts table. "
+              .format(channel_id) + "Letting Slack retry this event")
+        return lambda_error
+
+    item = response['Item']
+
+    if 'sheet_url' in item:
+        print("Info: channel_id {} already has sheet_url {}. Exiting."
+              .format(channel_id, item['sheet_url']))
+        return lambda_success
+
+    # Remove any None items from our item before updating
+    if not item['url']:
+        del item['url']
+
+    # Before launching into sheet creation, indicate that we're doing this
+    # in the database. This way, if we take too long to create the sheet
+    # and Slack retries the event, that next event will see this 'pending'
+    # string and cleanly return (eliminating all future retries).
+    item['sheet_url'] = 'pending'
+    hunts_table.put_item(Item=item)
+
+    # Also, let the channel users know what we are up to
+    turb.slack_client.chat_postMessage(
+        channel=channel_id,
+        text="Welcome to the channel for the {} hunt! ".format(item['name'])
+        + "Please wait a minute or two while I create some backend resources.")
+
+    # Create a sheet for the channel
+    sheet = turbot.sheets.sheets_create(turb, channel_name)
+
+    # Update the database with the URL of the sheet
+    item['sheet_url'] = sheet['url']
+    hunts_table.put_item(Item=item)
+
+    # Message the channel with the URL of the sheet
+    turb.slack_client.chat_postMessage(channel=channel_id,
+                                       text="Sheet created for this hunt: {}"
+                                       .format(sheet['url']))
+
+    # Create a database table for this hunt's puzzles
+    table = turb.db.create_table(
+        TableName=channel_name,
+        KeySchema=[
+            {'AttributeName': 'channel_id', 'KeyType': 'HASH'}
+        ],
+        AttributeDefinitions=[
+            {'AttributeName': 'channel_id', 'AttributeType': 'S'}
+        ],
+        ProvisionedThroughput={
+            'ReadCapacityUnits': 5,
+            'WriteCapacityUnits': 5
+        }
+    )
+
+    # Wait until the table exists
+    table.meta.client.get_waiter('table_exists').wait(TableName=channel_name)
+
+    # Mark the hunt as active in the database
+    item['active'] = True
+    hunts_table.put_item(Item=item)
+
+    # Message the hunt channel that the database is ready
+    turb.slack_client.chat_postMessage(
+        channel=channel_id,
+        text="Thank you for waiting. This hunt is now ready to begin! "
+        + "Use `/puzzle` to create puzzles for the hunt.")
+
+    return lambda_success
+
+def puzzle_channel_created(turb, puzzle_channel_name, puzzle_channel_id):
+    """Creates sheet and invites user for a newly-created puzzle channel"""
+
+    hunt_id = puzzle_channel_name.split('-')[0]
+
+    # First see if we can find an entry for this puzzle in the database.
+    # If not, simply return an error and let Slack retry
+    puzzle_table = turb.db.Table(hunt_id)
+    response = puzzle_table.get_item(
+        Key={'channel_id': puzzle_channel_id},
+        ConsistentRead=True
+    )
+    if 'Item' not in response:
+        print("Warning: Cannot find channel_id {} in {} table. "
+              .format(puzzle_channel_id, hunt_id)
+              + "Letting Slack retry this event")
+        return lambda_error
+
+    item = response['Item']
+
+    if 'sheet_url' in item:
+        print("Info: channel_id {} already has sheet_url {}. Exiting."
+              .format(puzzle_channel_id, item['sheet_url']))
+        return lambda_success
+
+    # Remove any None items from our item before updating
+    if not item['url']:
+        del item['url']
+
+    # Before launching into sheet creation, indicate that we're doing this
+    # in the database. This way, if we take too long to create the sheet
+    # and Slack retries the event, that next event will see this 'pending'
+    # string and cleanly return (eliminating all future retries).
+    item['sheet_url'] = 'pending'
+    puzzle_table.put_item(Item=item)
+
+    # Create a sheet for the puzzle
+    sheet = turbot.sheets.sheets_create_for_puzzle(turb, puzzle_channel_name)
+
+    # Update the database with the URL of the sheet
+    item['sheet_url'] = sheet['url']
+    puzzle_table.put_item(Item=item)
+
+    # Message the channel with the URL of the puzzle's sheet
+    turb.slack_client.chat_postMessage(channel=puzzle_channel_id,
+                                       text="Sheet created for this puzzle: {}"
+                                       .format(sheet['url']))
+
+    hunts_table = turb.db.Table('hunts')
+    response = hunts_table.scan(
+        FilterExpression='hunt_id = :hunt_id',
+        ExpressionAttributeValues={':hunt_id': hunt_id},
+    )
+
+    if 'Items' in response:
+
+        hunt_channel_id=response['Items'][0]['channel_id']
+
+        # Find all members of the hunt channel
+        members = turbot.slack.slack_channel_members(turb.slack_client,
+                                                     hunt_channel_id)
+
+        # Filter out Turbot's own ID to avoid inviting itself
+        members = [m for m in members if m != TURBOT_USER_ID]
+
+        turb.slack_client.chat_postMessage(
+            channel=puzzle_channel_id,
+            text="Inviting all members from the hunt channel:  {}"
+            .format(hunt_id))
+
+        # Invite those members to the puzzle channel (in chunks of 500)
+        cursor = 0
+        while cursor < len(members):
+            turb.slack_client.conversations_invite(
+                channel=puzzle_channel_id,
+                users=members[cursor:cursor + 500])
+            cursor += 500
+
+    return lambda_success
+
+def channel_created(turb, event):
+    print("In channel_created with event: {}".format(str(event)))
+
+    channel = event['channel']
+    channel_id = channel['id']
+    channel_name = channel['name']
+    creator = channel['creator']
+
+    # Ignore any channels that turbot didn't create
+    if creator != TURBOT_USER_ID:
+        print("channel_created: Not a turbot-created channel. Exiting.")
+        return lambda_success
+
+    # The presence of a hyphen determines whether this is a puzzle
+    # channel or a hunt channel.
+    if '-' in channel_name:
+        return puzzle_channel_created(turb, channel_name, channel_id)
+    else:
+        return hunt_channel_created(turb, channel_name, channel_id)
 
-events = {
-    "app_home_opened": app_home_opened
-}
+events['channel_created'] = channel_created
diff --git a/turbot/interaction.py b/turbot/interaction.py
index f634cbc..8c1304a 100644
--- a/turbot/interaction.py
+++ b/turbot/interaction.py
@@ -8,8 +8,6 @@ import re
 import requests
 from botocore.exceptions import ClientError
 
-TURBOT_USER_ID = 'U01B9QM4P9R'
-
 actions = {}
 commands = {}
 submission_handlers = {}
@@ -86,6 +84,7 @@ def new_hunt_submission(turb, payload, metadata):
     function above."""
 
     state = payload['view']['state']['values']
+    user_id = payload['user']['id']
     name = state['name']['name']['value']
     hunt_id = state['hunt_id']['hunt_id']['value']
     url = state['url']['url']['value']
@@ -131,12 +130,6 @@ def new_hunt_submission(turb, payload, metadata):
                                 "Error creating Slack channel: {}"
                                 .format(e.response['error']))
 
-    if not response['ok']:
-        return submission_error("name",
-                                "Error occurred creating Slack channel "
-                                + "(see CloudWatch log")
-
-    user_id = payload['user']['id']
     channel_id = response['channel']['id']
 
     # Create a sheet for the channel
@@ -145,46 +138,21 @@ def new_hunt_submission(turb, payload, metadata):
     channel_id = response['channel']['id']
 
     # Insert the newly-created hunt into the database
+    # (leaving it as non-active for now until the channel-created handler
+    #  finishes fixing it up with a sheet and a companion table)
     hunts_table.put_item(
         Item={
             'channel_id': channel_id,
-            "active": True,
+            "active": False,
             "name": name,
             "hunt_id": hunt_id,
-            "url": url,
-            "sheet_url": sheet['url']
+            "url": url
         }
     )
 
     # Invite the initiating user to the channel
     turb.slack_client.conversations_invite(channel=channel_id, users=user_id)
 
-    # Message the channel with the URL of the sheet
-    turb.slack_client.chat_postMessage(channel=channel_id,
-                                       text="Sheet created for this hunt: {}"
-                                       .format(sheet['url']))
-
-    # Create a database table for this hunt's puzzles
-    table = turb.db.create_table(
-        TableName=hunt_id,
-        AttributeDefinitions=[
-            {'AttributeName': 'channel_id', 'AttributeType': 'S'}
-        ],
-        KeySchema=[
-            {'AttributeName': 'channel_id', 'KeyType': 'HASH'}
-        ],
-        ProvisionedThroughput={
-            'ReadCapacityUnits': 5,
-            'WriteCapacityUnits': 4
-        }
-    )
-
-    # Message the hunt channel that the database is ready
-    turb.slack_client.chat_postMessage(
-        channel=channel_id,
-        text="Welcome to your new hunt! "
-        + "Use `/puzzle` to create puzzles for the hunt.")
-
     return {
         'statusCode': 200,
     }
@@ -298,9 +266,6 @@ def puzzle_submission(turb, payload, metadata):
     This is the modal view presented to the user by the puzzle function
     above."""
 
-    print("In puzzle_submission\npayload is: {}\nmetadata is {}"
-          .format(payload, metadata))
-
     meta = json.loads(metadata)
     hunt_id = meta['hunt_id']
     hunt_channel_id = meta['hunt_channel_id']
@@ -329,12 +294,8 @@ def puzzle_submission(turb, payload, metadata):
 
     puzzle_channel_id = response['channel']['id']
 
-    # Create a sheet for the puzzle
-    sheet = turbot.sheets.sheets_create_for_puzzle(turb, hunt_dash_channel)
-
     # Insert the newly-created puzzle into the database
     table = turb.db.Table(hunt_id)
-
     table.put_item(
         Item={
             "channel_id": puzzle_channel_id,
@@ -343,32 +304,9 @@ def puzzle_submission(turb, payload, metadata):
             "name": name,
             "puzzle_id": puzzle_id,
             "url": url,
-            "sheet_url": sheet['url']
         }
     )
 
-    # Find all members of the hunt channel
-    members = turbot.slack.slack_channel_members(turb.slack_client,
-                                                 hunt_channel_id)
-
-    # Filter out Turbot's own ID to avoid inviting itself
-    members = [m for m in members if m != TURBOT_USER_ID]
-
-    turb.slack_client.chat_postMessage(channel=puzzle_channel_id,
-                                       text="Inviting members: {}".format(str(members)))
-
-    # Invite those members to the puzzle channel (in chunks of 500)
-    cursor = 0
-    while cursor < len(members):
-        turb.slack_client.conversations_invite(
-            channel=puzzle_channel_id,
-            users=members[cursor:cursor + 500])
-        cursor += 500
-
-    # Message the channel with the URL of the puzzle's sheet
-    turb.slack_client.chat_postMessage(channel=puzzle_channel_id,
-                                       text="Sheet created for this puzzle: {}"
-                                       .format(sheet['url']))
     return {
         'statusCode': 200
     }
diff --git a/turbot_lambda/turbot_lambda.py b/turbot_lambda/turbot_lambda.py
index 7469222..e19e96d 100644
--- a/turbot_lambda/turbot_lambda.py
+++ b/turbot_lambda/turbot_lambda.py
@@ -124,10 +124,11 @@ def url_verification_handler(turb, body):
     }
 
 def event_callback_handler(turb, body):
-    type = body['event']['type']
+    event = body['event']
+    type = event['type']
 
     if type in turbot.events.events:
-        return turbot.events.events[type](turb, body)
+        return turbot.events.events[type](turb, event)
     return error("Unknown event type: {}".format(type))
 
 def turbot_interactive_or_slash_command(turb, event, context):