add banker bot example and minor README changes

CHANGELOG.md

@@ -8,7 +8,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [0.3.0] - 2021-06-30
 ### Added
-- Support for FallbackIntent
+- Support to update the Fallback Intent
+- Example bot based on the [AWS Workshop](https://amazonlex.workshop.aws/) to
+  illustrate how to configure Lambda CodeHooks and Conversation Logs
 
 ## [0.2.0] - 2021-06-29
 ### Added

README.md

@@ -270,6 +270,11 @@ Lex APIS.
   an existing working bot version and restore it into the current `DRAFT`
   using the Lex import functionality
 - Lex Bot Resource Policies are not implemented
+- The Custom Resource stack deploys a regular IAM Role instead of an IAM Service
+  Linked Role to be used with the Lex Bot. The SAR service does not currently
+  [support](https://docs.aws.amazon.com/serverlessrepo/latest/devguide/list-supported-resources.html)
+  Service Linked Roles. We may change this if support is added. You can create
+  your own Service Linked Role separately and use it in your template
 
 ## Development
 

examples/banker-bot/README.md

@@ -0,0 +1,18 @@
+This example deploys a Banker Bot based on the [Lex V2 Workshop](https://amazonlex.workshop.aws/)
+which showcases various Lex V2 capabilities.
+
+The template shows how to attach a [Lambda Fulfillment Code Hook](https://docs.aws.amazon.com/lexv2/latest/dg/lambda.html)
+and how to configure [Text Conversation Logs](https://docs.aws.amazon.com/lexv2/latest/dg/conversation-logs-configure.html)
+
+Before you use this example, you should deploy the Custom Resource stack
+in your AWS account. The Custom Resource stack name is passed as a parameter
+when deploying this example. This stack name parameter is used to import the
+values of the Lambda function and the IAM role created by the Custom Resource.
+
+The bot in this example can be deployed using the
+[AWS Serverless Application Model Command Line Interface (SAM CLI)](https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/what-is-sam.html):
+
+```bash
+sam build --use-container
+sam deploy --guided
+```

examples/banker-bot/samconfig.toml

@@ -0,0 +1,15 @@
+# https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-sam-cli-config.html
+# https://aws.amazon.com/blogs/compute/optimizing-serverless-development-with-samconfig/
+
+version=0.1
+[default.deploy.parameters]
+stack_name = "lex-v2-cfn-cr-banker-bot"
+s3_bucket = "lex-v2-cfn-cr-artifacts-506886316466-us-east-1"
+s3_prefix = "sam-artifacts/lex-v2-cfn-banker-bot"
+region = "us-east-1"
+fail_on_empty_changeset = false
+confirm_changeset = true
+capabilities = "CAPABILITY_IAM CAPABILITY_AUTO_EXPAND"
+parameter_overrides = """
+  LexV2CfnCrStackName=lex-v2-cfn-cr \
+"""

examples/banker-bot/src/lambda_functions/banker_bot/lambda_function.py

@@ -0,0 +1,118 @@
+"""
+MIT No Attribution
+
+Copyright 2021 Amazon Web Services
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this
+software and associated documentation files (the "Software"), to deal in the Software
+without restriction, including without limitation the rights to use, copy, modify,
+merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+"""
+
+# https://amazonlex.workshop.aws/banker-bot/create-first-lambda.en.files/BankingBotEnglish.py
+
+import json
+import random
+import decimal 
+
+def random_num():
+    return(decimal.Decimal(random.randrange(1000, 50000))/100)
+
+def get_slots(intent_request):
+    return intent_request['sessionState']['intent']['slots']
+
+def get_slot(intent_request, slotName):
+    slots = get_slots(intent_request)
+    if slots is not None and slotName in slots and slots[slotName] is not None:
+        return slots[slotName]['value']['interpretedValue']
+    else:
+        return None    
+
+def get_session_attributes(intent_request):
+    sessionState = intent_request['sessionState']
+    if 'sessionAttributes' in sessionState:
+        return sessionState['sessionAttributes']
+
+    return {}
+
+def elicit_intent(intent_request, session_attributes, message):
+    return {
+        'sessionState': {
+            'dialogAction': {
+                'type': 'ElicitIntent'
+            },
+            'sessionAttributes': session_attributes
+        },
+        'messages': [ message ] if message != None else None,
+        'requestAttributes': intent_request['requestAttributes'] if 'requestAttributes' in intent_request else None
+    }
+
+
+def close(intent_request, session_attributes, fulfillment_state, message):
+    intent_request['sessionState']['intent']['state'] = fulfillment_state
+    return {
+        'sessionState': {
+            'sessionAttributes': session_attributes,
+            'dialogAction': {
+                'type': 'Close'
+            },
+            'intent': intent_request['sessionState']['intent']
+        },
+        'messages': [message],
+        'sessionId': intent_request['sessionId'],
+        'requestAttributes': intent_request['requestAttributes'] if 'requestAttributes' in intent_request else None
+    }
+
+def CheckBalance(intent_request):
+    session_attributes = get_session_attributes(intent_request)
+    slots = get_slots(intent_request)
+    account = get_slot(intent_request, 'accountType')
+    #The account balance in this case is a random number
+    #Here is where you could query a system to get this information
+    balance = str(random_num())
+    text = "Thank you. The balance on your "+account+" account is $"+balance+" dollars."
+    message =  {
+            'contentType': 'PlainText',
+            'content': text
+        }
+    fulfillment_state = "Fulfilled"    
+    return close(intent_request, session_attributes, fulfillment_state, message)   
+
+def FollowupCheckBalance(intent_request):
+    session_attributes = get_session_attributes(intent_request)
+    slots = get_slots(intent_request)
+    account = get_slot(intent_request, 'accountType')
+    #The account balance in this case is a random number
+    #Here is where you could query a system to get this information
+    balance = str(random_num())
+    text = "Thank you. The balance on your "+account+" account is $"+balance+" dollars."
+    message =  {
+            'contentType': 'PlainText',
+            'content': text
+        }
+    fulfillment_state = "Fulfilled"    
+    return close(intent_request, session_attributes, fulfillment_state, message)
+
+
+def dispatch(intent_request):
+    intent_name = intent_request['sessionState']['intent']['name']
+    response = None
+    # Dispatch to your bot's intent handlers
+    if intent_name == 'CheckBalance':
+        return CheckBalance(intent_request)
+    elif intent_name == 'FollowupCheckBalance':
+        return FollowupCheckBalance(intent_request)
+
+    raise Exception('Intent with name ' + intent_name + ' not supported')
+
+def lambda_handler(event, context):
+    response = dispatch(event)
+    return response