How to compare entered input emailaddresses and the api emailaddresses

Question

Requirement is I will be entering emailaddresses on UI and it will be passed to the integration and the integration will return the emailAddresses with GUIDs . If any emailaddress is missing from the response which we entered then it must show that emailaddress on UI. Suppose I have passed test@test.com and test2@test.com and In repsonsed I get only GUID of only one emailaddress then it has to show the 2nd emailaddress on the UI as invalid error . How Can I achieve it

Mike Schmitt · Answer

a!forEach(
 pv!jsonPv,
 if(
 contains(pv!emailPv, fv!item.emailAddress),
 {},
 "This one is invalid: " & fv!item.emailAddress
 )
)

Mike Schmitt · Answer

Then you can replace the code in line 4 to check for any condition you need. I'm not exactly sure what you're saying you need, without some more detailed context and/or example outputs and logic, but it should be pretty simple to check each return line item for any condition you want and filter what you need it to.

Mike Schmitt · Answer

So in this case you simply need to adjust where and how you filter. Assuming you have access to the original list of email addresses as well as the API response, you simply iterate through all original email addresses and check whether that address was mentioned in the API response values, and if not, return it as an "invalid" one. 
 a!localVariables(
 local!initialEmailAddressList: {
 "test1@test.com",
 "test2@test.com",
 "testInvalid@test.com",
 "test3@test.com"
 },
 
 local!simulatedApiFeedback: {
 a!map(
 email: "test1@test.com",
 uuid: "asdf1234QWER"
 ),
 a!map(
 email: "test2@test.com",
 uuid: "asdf1234QWER"
 ),
 a!map(
 email: "test3@test.com",
 uuid: "asdf1234QWER"
 )
 },
 
 /* get any invalid email addresses by comparing the original list with the API feedback list */
 a!flatten(a!forEach(
 local!initialEmailAddressList,
 if(
 contains( local!simulatedApiFeedback.email, fv!item ),
 {},
 fv!item
 )
 ))
)

Mike Schmitt · Answer

ZAINAB said: contains( pv!JsonPv, fv!item ), 
 Why would "pv!JsonPv" contain the email address? pv!JsonPv is a map, not a string. Did you try "contains(pv!JsonPv.emailAddress, fv!item)"? My example code above clearly showed that the "contains()" call should check the list of map properties, not the map itself.

Mike Schmitt · Answer

ZAINAB said: If i create expressionrule then we would need data to be stored but as per the requirement it shold be stored only when there is no invalid emails 
 I'm not sure what you mean. An expression rule doesn't "store" anything that the process instance isn't already storing. Your expression rule should mirror (almost exactly) the code in your script task (only) and accept the email list and the JSON list as inputs, and should output only your "invalid email address".

Mike Schmitt · Answer

ZAINAB said: For expression rule ,doesn't it required to call data from DB ? 
 Absolutely not - expression rules can handle any arbitrary input data, almost exactly like a script task in a process model would (but much easier to edit and test). You would just pass in your PV data and have it do whatever complex processing you need, and save the output to a PV (just like you do in your script task). 
 Have you taken the online Appian training? Knowing how to use expression rules is ABSOLUTELY CRITICAL in effective Appian development. 
 ZAINAB said: how can I create expressionrule 
 various ways - the "official" way is you go to your application object and click "create" -> "expression rule". However for quick testing you can create a new/unsaved expression rule simply by going to "yourenvironmenturl.com /suite/design/rule ", which will load the (blank) expression rule editor.