Question

what is difference between epv and env?

Answer 1

EPV vs ENV/SERVER configuration

EPV - Exposed Process Value

ENV - Environment Variable

1. EPV can hold a variable of any type ENV is always a string

2. EPV is generally business data which needs to be injected altered runtime into a Process or service, ENV is as the name suggests

   environment configuration variables/parameters e.g. WSDL URL, jndi Name, email distribution lists etc.

3. Both can be changed at runtime from Process Admin Console, though env variables are designed to be set with the code.

4. To change and EPV you need to schedule a time when the change gets effected.

5. EPV is not specific to the environment but ENV has multiple possible valies e.g. default, development, test, staging, production which gets

   applied to the environemtn type.

6. SERVER configurations are an extension to ENVs specialized to be server confirations for SOAP endpoints, REST endpoints and ECM endpoints

7. usage/access

EPV value

tw.local.myvar=String(tw.epv.maintenance.email);

get EPV at specified time

tw.local.myvar=String(tw.epv.maintenance.email.valueAt(newTWDate("2015-10-19 11:30:00.0")));

8. Update from javascript API

EPV

tw.epv.maintenance.email.update("abcd@abcd.com",new TWDate("2015-10-19 11:01:00.0"));

ENV

tw.env.update(tw.system.model.env.benefitservice, "https://someurl.com/svc?wsdl");

9. How to make available realtime in Coach View

You can do an ajax call/service call to a service which can retrieve the current value and return it.

Answer 2

EPV variables are used where you need to change those on the fly and your process application will use the upadted values.

ENV variables are used to store your env related information like DEV-QA-UAT etc. It will be applicable to those environments only.

Answer 3

The env variables are used and defined based on the environment dev, test and production etc . These values does not change frequently and can be changed from ProcessAdmin -->Installed app --> Environment Variable tabs. Once changes , it will be changed immediately. The ENV values can be changed by Admin Group only.

The EPV can be searched and changed using ProcessAdmin -->Server Admin --> Admin Tools --> EPV.  EPV Value changes can be scheduled using the tool. and It will be effective on the specified time . EPV are exposed to certain group and group member also can change the EPV value .

Answer 4

EPV variables are business variable which we can change via process Admin. Example Interest rate.

ENV are non business variable also we can change via process admin.Example Datasource.

Answer 5

EPVs are used to bind centrally defined variables of different types to BPDs and services, they can be changed at run time and are meant to provide simple means of interjecting into a running process service before its next lookup of the EPV variable. A good example will be to enable/disable a maintenance application not available state.

Environment variable on the other hand (can also be changed at run time though) are more geared towards storing a set of parameters e.g. web service hostname per environmement (DEV, SIT, QA, PROD), you can store things like jndi names, java application integration urls, environment identifers themselves, email sender addresses, admin groups etc.

Answer 6

The answer an interview is expecting would be this

-- EPV is Business related constants which may change in future. For e.g. Interest Rates, Service Charges, etc.

-- Environment variable is Non-Business related constant which may change in future. For e.g. DataSource (Dev/QA/Prod)

Answer 7

More insight on this ENV variable is performance wise expensive as compared to EPV.

Answer 8

https://youtu.be/pVk5sIHW_SM