#718 OIC Process - Decisions: Contexts, Lists, Relations and other features

Leading on from the previous post -

Again, text taken from the Oracle docs in italics.


There are a couple of more goodies in the Decisions pack.

Contexts

A context is a collection of one or more key-value pairs with an optional result field. Each pair is called a context entry. The key attribute within a context entry acts as an identifier to its corresponding value attribute. You can use a context to collectively document all decision logic related to a particular scenario or entity. Say you need to determine the loan eligibility of an applicant, based on the applicant’s net monthly income and expense. For this purpose, you can create a decision named Loan Eligibility using the Context notation and add expressions or

logic for gross monthly income, monthly expense, and net monthly income. Then, you can either add a result field (within the context) that evaluates the net income and expense for loan eligibility, or you can choose to evaluate these within another decision.

Ok, so let's try this out, based on our Order payload  -

I can now test this -

first with a small order...

then with a large order...

Very succinct and easy to use.

Contexts can be referenced from Decision Tables -

Lists

A list notation is a vertical list of elements, where each element is an independent logical

notation. The output of a list notation contains outputs of all its elements. You can

also invoke the output of a particular list element from another decision.

Now did you understand the above?
Let's make it a bit more tangible. Here is my list, containing 5 products.

Lists can be referenced in Decision Tables -

Here I am setting the discount to the sum of the entries in the Product List.

Makes no sense from a functional perspective, but just to illustrate usage.

Relations

Think of a DB table e.g. Products relation

So now to a simple test - using the Decision table from the previous post -

Line 6 makes no functional sense, but demonstrates how one can leverage
relations in a DT.

I will enter an order for 123 items with a total value of 12000.
As this has a hit policy of C+ we should get a final discount based on the
values for the 3 rules which will fire (Rules 4,5,6) so that is
16+25 + price of the iBike, 1300 = 1341

Test -

 

Functions

You can create functions to define specific operations that aren’t available through

built-in functions. In Process, decisions created using the Function notation return a

value only when invoked from another decision.

Functions can be called from a DT.

Test with the following payload -

Imbolc Discount defined as -

(price * quantity) / 100

Do the math - 1234 * 8 = 9872.

Divide by 100 = 98.72

Loops

Create loops to iterate over lists or arrays. Using the loop logical notation, you can

create three different types of loops, namely For, Some, and Every.

• For: Iterates over a list and returns an expression.

• Some: Checks if at least one list item satisfies the test condition defined by an expression

and returns a Boolean value.

• Every: Checks if every list item satisfies the test condition defined by an expression

and returns a Boolean value.

I test...

Note: the loop executes for each member of the list [1,2,3,4].

Check out the other operation options -

Some:

Test...

Every:

Test...