fundamentals-lp-lab3.md

Lab3

Learning objective: To perform actions in an iterative fashion on a list of contracts

Prerequisite

1. Daml SDK installed and setup
2. Daml Fundamentals Training: Canton Ledger Programming in Daml - Lessons 1 to 9 completed.

Scenario:

The Epic Airlines (EA) needs to implement its Customer Loyalty Program (CLP) using Daml. Customers can register for CLP anytime. When they register, they get a CLP-account to store their loyalty points.

Continuing from the previous Lab, there are two templates - CLPAApplication and CLPAccount. There is no change required in the code written for these two templates.

Problem statement 1

This problem has two parts

1. Here is a script that creates CLPApplications for Alice and Bob.

   testActionsLoops: Script () 
   testActionsLoops = script do 
       alice <- allocateParty "Alice"
       bob <- allocateParty "Bob"
       airline <- allocateParty "Epic Airlines"
       
       setTime (time (date 2023 Mar 01) 10 30 0)
       now <- getTime 
   
       -- Alice creates a blank CLPApplication
       aliceCLPAppId <- submit alice do         
           createCmd CLPApplication with  
               customer = alice 
               airline = airline 
               id = ""
               name = ""
               address = ""
               email = ""
               phone = Some ""
               timestamp = now 
               dob = toDateUTC now
   
       -- Alice submits the application with details filled in
       aliceCLPAppId <- submit alice do 
           exerciseCmd aliceCLPAppId SubmitApplication 
               with
                   appCustomer = alice 
                   appAirline = airline
                   customerId = "123"
                   customerName = "Alice"
                   customerAddress = "123 Main St ABCD"
                   customerEmail = "alice@wonderland.io"
                   customerPhone = "+01-555-555-1234"
                   appTimeStamp = now
                   customerDob = date 2000 Jan 05    
   
       -- Bob creates a blank application
       bobCLPAppId <- submit bob do         
           createCmd CLPApplication with  
               customer = bob 
               airline = airline 
               id = ""
               name = ""
               address = ""
               email = ""
               phone = Some ""
               timestamp = now 
               dob = toDateUTC now
   
   -- Bob submits application with details filled in
       bobCLPAppId <- submit bob do 
           exerciseCmd bobCLPAppId SubmitApplication 
               with
                   appCustomer = bob 
                   appAirline = airline
                   customerId = "234"
                   customerName = "Bob"
                   customerAddress = "123 Spring St EFGH"
                   customerEmail = "bob@nomansland.io"
                   customerPhone = "+01-555-555-5678"
                   appTimeStamp = now
                   customerDob = date 2010 Jan 05    
   

   Once the above script is run, it should show the following output:

   

   Extend this script to perform the following actions:

   1. The airline queries for all the applications and stores them in allApplications which will be a list of tuples (ContractId, Contract payload)
   2. Extract all contract-ids from allApplications and store them in allApplicationCids
   3. Extract all customer-ids from contract payloads in allApplications and store them in allCustomerIds
   4. Create a new list allCidsAndIds of tuples (ContractId, Text) by pairing elements from allApplicationCids and allCustomerIds

   The following debug statements

       debug allApplications
       debug allApplicationCids 
       debug allCidsAndIds
   

   should print the output as shown below

   Trace: 
   [(00aedaddf8684f16bc52e14bf9dac7aeca0c4d7f1d823a7d5420694c8fa7ead7f9,CLPApplication {customer = 'Alice', airline = 'Epic Airlines', id = "123", name = "Alice", address = "123 Main St ABCD", email = "alice@wonderland.io", phone = Some "+01-555-555-1234", timestamp = 2023-03-01T10:30:00Z, dob = 2000-01-05}),(00bdc5727349c856efda728e229f546272586478b258bf83eb724fe3c216c83b65,CLPApplication {customer = 'Bob', airline = 'Epic Airlines', id = "234", name = "Bob", address = "123 Spring St EFGH", email = "bob@nomansland.io", phone = Some "+01-555-555-5678", timestamp = 2023-03-01T10:30:00Z, dob = 2010-01-05})]
   [00aedaddf8684f16bc52e14bf9dac7aeca0c4d7f1d823a7d5420694c8fa7ead7f9,00bdc5727349c856efda728e229f546272586478b258bf83eb724fe3c216c83b65]
   [(00aedaddf8684f16bc52e14bf9dac7aeca0c4d7f1d823a7d5420694c8fa7ead7f9,"123"),(00bdc5727349c856efda728e229f546272586478b258bf83eb724fe3c216c83b65,"234")]
   

   Hints:

   Here are some of the functions that you may find useful:

   • query
   • map
   • zip

2. In this part, continue to extend the previous script that performs the following

   • The airline submits a transaction that exercises ReviewApplication choices on all the applications and returns a list of CLPAccounts created. This list is stored in allAccountCids.
   • With the accounts created in the previous step, the airline now exercises the AddPoints choice and adds 1000 points to each account.

   Once the above script is executed, it should have two accounts as shown below:

   

   Add the following statements at the end of your script:

   allAccountTuples <- query @CLPAccount airline
   
       debug allAccountCids 
       debug allAccountTuples 
   

   The Transaction Tree view of the script output should show the following output:

   [Some 0050eb35ab8c025a0c59a15d5684355cc2d0a2cd4cad8004435a6818ef12192731,Some 005f605dc5ed79d9a98489ce31421d64d365ca550827954cb160c94154d2ef09c1]
   [(00691fb3d8526dc650dee23e15351e16272d18f59e3958a25a3629a784a85b85fc,CLPAccount {customer = 'Alice', airline = 'Epic Airlines', id = "123", name = "Alice", address = "123 Main St ABCD", email = "alice@wonderland.io", phone = Some "+01-555-555-1234", timestamp = 2023-03-01T10:30:00Z, dob = 2000-01-05, points = 1000}),(00b325433392e50fe1f60b06b90671e067df8f08f1332cb0b0c82d950b9ef80d19,CLPAccount {customer = 'Bob', airline = 'Epic Airlines', id = "234", name = "Bob", address = "123 Spring St EFGH", email = "bob@nomansland.io", phone = Some "+01-555-555-5678", timestamp = 2023-03-01T10:30:00Z, dob = 2010-01-05, points = 1000})]