This presentation covers how to build a chatbot - step by step. It covers Facebook, integration using AWS Lex and AWS Lambda

1. Building a chatbot – step by step
Srushith R
srushith@codeops.tech

2. What is this bot all about?
• This is a bot for buying books – ‘Amazon
BookBot’
• You can interact with this bot to find out
relevant technical books on the given topic
available in Amazon
• For each book, you can find out book details
(author, price, reviews, availability, etc.)
• This bot can be integrated with
FaceBook/Slack

3. Technologies
• Amazon Web Services
– AWS Lex – for Natural Language Processing (NLP)
– AWS Lambda – for the back-end serverless
function(s)
• Python 2.7 – for the serverless function code
– python-amazon-simple-product-api 2.2.11 - A
Python wrapper for the Amazon.com Product
Advertising API (for getting book information from
Amazon)

4. Installation (for hands-on)
• AWS account
– Preferably AWS CLI installed
• Python 2.7 installed
• Python module installed: python-amazon-
simple-product-api 2.2.11
Note: The Python module and the source code
must be available in the same folder (for
uploading into AWS Lambda)

5. Roadmap
1. Write a python code to get book details given
a keyword from Amazon
2. Create a Lambda function
3. Create a chat bot using AWS Lex
4. Integrate with facebook

6. Getting started
• The core functionality of fetching the details
of book(s) given the keyword can be
implemented as a simple Python code first
– This will reduce your effort in coding, debugging
and testing your Python code
– The same functionality can be integrated as an
AWS Lambda function later
– Here is the sample code with its invocation sample
as an example

7. Python code

8. Output
$ python books.py
1 The DevOps Handbook: How to Create World-Class Agility, Reliability, and Security in
Technology Organizations
2 The Phoenix Project: A Novel about IT, DevOps, and Helping Your Business Win
3 What is DevOps?
4 DevOps Handbook: A Guide To Implementing DevOps In Your Workplace
5 The DevOps 2.0 Toolkit: Automating the Continuous Deployment Pipeline with
Containerized Microservices
6 Building a DevOps Culture
7 The Phoenix Project: A Novel About IT, DevOps, and Helping Your Business Win
8 The DevOps 2.1 Toolkit: Docker Swarm: Building, testing, deploying, and monitoring
services inside Docker Swarm clusters (The DevOps Toolkit Series) (Volume 2)
9 5 Unsung Tools of DevOps
10 Effective DevOps: Building a Culture of Collaboration, Affinity, and Tooling at Scale

10. Tweak the code
• Regardless of the language you choose, there
is a common pattern to writing code for a
Lambda function that includes the following
core concepts:
– Handler: Handler is the function AWS Lambda
calls to start execution of your Lambda function
– The context object: Via context object your code
can interact with AWS Lambda

11. Lets log!
• Add logging statements to the Python code to
see what exactly is happening in the
background. There are two ways to log:
– Use of print statements: all print statements are
by default logged into CloudWatch
– Use ‘logging’ module in python: logging.*
functions write additional information to each log
entry, such as time stamp and log level.

12. IAM role for logging
• IAM (Identity & Access Management) role is
similar to an user, in that it is an AWS identity
with permission policies that determine what
the identity can and cannot do in AWS
• It is a service that logs AWS events made by or
on behalf of your AWS account
• Create an IAM role to be used for logging.
– You should permit this role to log the data

13. Create an IAM role
Select IAM in the AWS services and select roles

14. Create an IAM role

15. Create an IAM role
select AWS
Lambda

16. Add policies to the role
add
AWSLambdaExecute and
AWSLambda FullAccess
policies to the role

17. Create an IAM role

18. IAM role

19. Changed code (for logging)

21. Create a Lambda function

22. Select a runtime and blueprint

23. Create Lambda function
inline code editing tab.
If the code is simple
(without any
dependencies), you can
add it here

24. Configure triggers
can choose any of
the triggers, but we
don’t require any in
this example

25. Folder with the dependencies
code with dependencies
must be uploaded as a
zip file with all the
necessary dependencies

26. Folder with the dependencies and the
source code

27. Zip them

28. The resulting zip file

29. Upload the zip file

30. Add environment variables

31. Specify the lambda handler and
choose a role for logging
handler format:
<Source code file
name>.lambda_handler
role with logging
permissions

32. Set the timeout
maximum
runtime of the
lambda function

33. Review the details

34. Review the details and create

35. Test the Lambda function

36. Configure the input test event

37. Save and test!

38. Lambda function output

39. Log output

40. Amazon Lex

41. Creating a bot using Lex

42. Creating bot using Lex

43. Add the bot details
maximum
inactive time

44. Create intent
create an
intent

45. Create intent

46. Create intent

47. Create intent

48. Utterances
add preferred
utterances – purchase
a <docker> book

49. Add Slots
add slots

50. Choose a Slot type
you can choose from
the existing templates
or create your own
slot type

51. Add Prompts
prompts are questions to
the users that help in
filling the slots

52. the moment slot ‘title’ is
entered, Lex recognises
it in the utterances
select if the
particular slot is a
compulsory one

53. Integrate Lex and Lambda
select the desired
lambda function
from the drop
down

54. Add permission

55. Save and build

56. Build

57. Its up and ready!

58. Lets test!

59. Oops!

60. Lets interrogate – check logs on
CloudWatch
But this is what we got:
Expected input:
{
“title” : “java”
}
{u'currentIntent': {u'slots': {u'title': u'java'}, u'name': u'get_book_titles',
u'confirmationStatus': u'None'}, u'bot': {u'alias': None, u'version': u'$LATEST', u'name':
u'BookBot'}, u'userId': u'dmfh3duubfag9vpt9a6va3sj153hfj70', u'inputTranscript':
u'suggest a java book', u'invocationSource': u'FulfillmentCodeHook',
u'outputDialogMode': u'Text', u'messageVersion': u'1.0', u'sessionAttributes': None}

61. How Lex communicates?
• Lex doesn’t just send the slot data, it sends much
more!
– currentIntent: has slots, name (the intent name) and
confirmationStatus
– bot:
• name – The name of the bot that processed the request
• alias – The alias of the bot version that processed the request.
• version – The version of the bot that processed the request.
– userId : This value is provided by the client application.
Amazon Lex passes it to the Lambda function.
– inputTranscript: The text used to process the request.

62. How Lex communicates?
• invocationSource:
– DialogCodeHook: Amazon Lex sets this value to
direct the Lambda function to initialize the
function and to validate the user's data input
– FulfillmentCodeHook: Amazon Lex sets this value
to direct the Lambda function to fulfill an intent.
• sessionAttributes: Application-specific session
attributes that the client sent in the request.
This plays an important role for conversational
bots, where a state has to be maintained

63. Change the code, again!

64. Test at the lambda end
Zip the folder with the dependencies again with the
updated code and test with the input:

65. Fingers crossed!
The output at the lambda console:

66. Lets test from the bot

67. Why me?

68. Current scenario

69. But why?
This is the reason:
Lex Lambda

70. Lex expects a particular format
Amazon Lex expects a response from a Lambda function in the
following format:

71. Lambda response format for Lex
• sessionAttributes: This field is optional
• dialogAction : The dialogAction field directs Amazon Lex to
the next course of action, and describes what to expect from
the user after Amazon Lex returns a response to the client.
The type field indicates the next course of action
– Close — Informs Amazon Lex not to expect a response
from the user
– ConfirmIntent — Informs Amazon Lex that the user is
expected to give a yes or no answer to confirm or deny the
current intent.
– Delegate — Directs Amazon Lex to choose the next course
of action based on the bot configuration.

72. Lambda response format for Lex
– ElicitIntent — Informs Amazon Lex that the user is
expected to respond with an utterance that
includes an intent
– ElictSlot — Informs Amazon Lex that the user is
expected to provide a slot value in the response

73. dialogAction - close

74. dialogAction - ConfirmIntent

75. dialogAction - delegate

76. dialogAction - ElicitIntent

77. dialogAction - ElicitSlot

78. Code change, one last time

79. Phew!

80. Integration with facebook

81. Integration with facebook
On the Facebook developer portal, create a
Facebook application and a Facebook page.
–App Secret for the Facebook App.
–Page Access Token for the Facebook page.

82. Create a facebook page

83. Facebook page

84. Facebook page - AmazonBooks

85. Create a facebook app
facebook developer portal

86. Create a new app

87. Security check

88. Facebook app - AmazonBot

89. Choose Messenger

90. Facebook Messenger platform

91. Generate page access token
Select the facebook page from the drop down

92. Allow permissions

93. Approve!

94. Page access token
Note down the page access token

95. Facebook app secret
Click on the dashboard to get the app secret

96. Connecting Lex and facebook

97. Channels in Lex
In AWS Lex, select the channels tab and fill in the details
for facebook integration

98. Aliases
An alias is a pointer to a specific version of an Amazon Lex bot.
Use an alias to allow client applications to use a specific version
of the bot without requiring the application to track which
version that is.
Go to the settings tab of AWS Lex and add a name and version
(Latest by default) and click on the add button

99. Add the details
verify token is used
for handshake
between Lex and
facebook
add the pre noted
page access token
and app secret

100. Callback URL
A callback URL is generated once the bot is activated. This URL is
used as the webhook URL at the facebook end

101. Webhook setup

102. Webhook setup
callback URL
and the same
verify token
from the Lex
end
Select messages,
messagin_postbacks
and messging_options

103. Subscribe the facebook page
select the facebook
(AmazonBooks) page
from the drop down

104. Subscribe the facebook page

105. Search for the facebook page in the
chat
Search for the page
in the chat or at
messenger.com

106. Finally!

107. Hooray!

108. • Check out www.CodeOps.tech/meetup for
upcoming meetups