This map defines a set of rules that must be evaluated to make a decision.

The general idea comes from the Decision Model and Notation (DMN) structure used in BPM but very adapted to the specific coreBOS environment and infrastructure.

You can find a few useful links about DMN here:

• DMN Tutorial
• DMN Tutorial (PDF)
• Decision Table Reference
• Decision Table Reference (PDF)
• Decision Table Constructor
• https://www.omg.org/spec/DMN/

The accepted format for this map is basically a set of rules which can be of three types:

• Expressions
• Condition Expression or Condition Query business map names/IDs
• Decision Tables

Expressions contain any workflow expression that can be evaluated in the context of the Decision Map. These are exactly like Condition Expression maps but written directly inside this business map.

This type is simply the name or CRMID of any existing Condition Expression or Condition Query business map, they will be loaded and evaluated in the context of the Decision Map

This type expects to have the values to search on inside a coreBOS module.

We will be able to define the conditions to filter the records in the module and then a set of search conditions to look for records.

<decision>
<hitPolicy></hitPolicy>  <!-- U F C A R G -->
<aggregate></aggregate>  <!-- only available if hitPolicy=G: sum,min,max,count -->
<rules>
<rule>
  <sequence></sequence>
  <expression></expression>
  <output></output>  <!-- ExpressionResult, FieldValue, crmObject, Row -->
</rule>
<rule>
  <sequence></sequence>
  <mapid></mapid>
  <output></output>  <!-- ExpressionResult, FieldValue, crmObject, Row -->
</rule>
<rule>
  <sequence></sequence>
  <decisionTable>
    <module></module>
    <conditions>  <!-- QueryGenerator conditions -->
        <condition>
          <input></input>  <!-- context variable name -->
          <operation></operation>  <!-- QueryGenerator operators -->
          <field></field>  <!-- fieldname of module -->
        </condition>
    </conditions>
    <orderby></orderby>  <!-- column to order the records by -->
    <searches>
      <search>
        <condition>
          <input></input>  <!-- context variable name -->
          <operation></operation>  <!-- QueryGenerator operators -->
          <field></field>  <!-- fieldname of module -->
        </condition>
      </search>
    </searches>
    <output></output>  <!-- fieldname or fieldnames separated by commas or star (*) for all fields -->
  </decisionTable>
  <output></output>  <!-- ExpressionResult, FieldValue, crmObject, Row -->
</rule>
</rules>
</decision>

• Unique: Only a single rule can be satisfied. The decision table result contains the output entries of the satisfied rule. If more than one rule is satisfied, the Unique hit policy is violated.
• First: Multiple rules can be satisfied. The decision table result contains only the output of the first satisfied rule.
• Collect: Multiple rules can be satisfied. The decision table result contains the output of all satisfied rules in an arbitrary order as a list.
• Any: Multiple rules can be satisfied. However, all satisfied rules must generate the same output. The decision table result contains only the output of one of the satisfied rules. If multiple rules are satisfied which generate different outputs, the hit policy is violated.
• RuleOrder: Multiple rules can be satisfied. The decision table result contains the output of all satisfied rules in the order of the rules in the decision table.
• aGgregate:
  • The SUM aggregator sums up all outputs from the satisfied rules.
  • The MIN aggregator can be used to return the smallest output value of all satisfied rules.
  • The MAX aggregator can be used to return the largest output value of all satisfied rules.
  • The COUNT aggregator can be used to return the count of satisfied rules.

Read the DMN Hit Policy reference

• ExpressionResult: whatever the expression returns will be returned
• FieldValue: we understand that the expression returns a field name which we will evaluate in the given context
• crmObject: we understand that the expression returns a CRM ID so we instantiate the module and return the fully-loaded object
• Row: will return the full row of fields indicated in the “output” directive

To execute a decision map and get the result we use the coreBOS Rules service. coreBOS Rule will see that the given map is actually a decision table and will evaluate the map with the given context.

$result = coreBOS_Rule::evaluate(put your decision map ID or name here, $context);

<decision>
<hitPolicy>U</hitPolicy>
<rules>
<rule>
  <sequence>1</sequence>
  <expression><![CDATA[if AND('$[season]'=='Fall', $[guestcount]<=8) then 'Spareribs' else '__DoesNotPass__' end]]></expression>
  <output>ExpressionResult</output>
</rule>
<rule>
  <sequence>2</sequence>
  <expression><![CDATA[if AND('$[season]'=='Winter', $[guestcount]<=8) then 'Roastbeef' else '__DoesNotPass__' end]]></expression>
  <output>ExpressionResult</output>
</rule>
<rule>
  <sequence>3</sequence>
  <expression><![CDATA[if AND('$[season]'=='Spring', $[guestcount]<=4) then 'Dry Aged Gourmet Steak' else '__DoesNotPass__' end]]></expression>
  <output>ExpressionResult</output>
</rule>
<rule>
  <sequence>4</sequence>
  <expression><![CDATA[if AND('$[season]'=='Spring', AND($[guestcount]>=5, $[guestCount]<=8)) then 'Steak' else '__DoesNotPass__' end]]></expression>
  <output>ExpressionResult</output>
</rule>
<rule>
  <sequence>5</sequence>
  <expression><![CDATA[if AND(OR('$[season]'=='Fall', OR('$[season]'=='Winter', '$[season]'=='Spring')), $[guestcount]>8) then 'Stew' else '__DoesNotPass__' end]]></expression>
  <output>ExpressionResult</output>
</rule>
<rule>
  <sequence>6</sequence>
  <expression><![CDATA[if '$[season]'=='Summer' then 'Light Salad and a nice Steak' else '__DoesNotPass__' end]]></expression>
  <output>ExpressionResult</output>
</rule>
</rules>
</decision>

Let's suppose we have a module called DecisionConditions with these fields:

• sequence
• season
• guestcountmin
• guestcountmax
• desireddish

and these records

<decision>
<hitPolicy>U</hitPolicy>
<rules>
<rule>
  <sequence>1</sequence>
  <decisionTable>
    <module>DecisionConditions</module>
    <orderby>sequence</orderby>  <!-- column to order the records by -->
    <searches>
      <search>
        <condition>
          <input>season</input>  <!-- context variable name -->
          <operation>e</operation>  <!-- QueryGenerator operators -->
          <field>season</field>  <!-- fieldname of module -->
        </condition>
        <condition>
          <input>guestcount</input>  <!-- context variable name -->
          <operation>ge</operation>  <!-- QueryGenerator operators -->
          <field>guestcountmin</field>  <!-- fieldname of module -->
        </condition>
        <condition>
          <input>guestcount</input>  <!-- context variable name -->
          <operation>le</operation>  <!-- QueryGenerator operators -->
          <field>guestcountmax</field>  <!-- fieldname of module -->
        </condition>
      </search>
    </searches>
    <output>desireddish</output>  <!-- fieldname -->
  </decisionTable>
  <output>FieldValue</output>
</rule>
</rules>
</decision>

In the example above I decided to add two columns for the Guest Count, in order to convert the range [5..8] into two records. In this mindset, I also use the value 10000 as an “infinite” value.

But the truth is that as the implementor of both the decision table map and module I have full control of how I want my users to define the conditions. Let's suppose that I want the users of the module to be able to define the condition with only one column for guest count like is reflected in the image. In this case, I would have implemented a module with these fields:

• sequence
• season
• guestcount
• desireddish

these records

and this map

<decision>
<hitPolicy>F</hitPolicy>
<rules>
<rule>
  <sequence>1</sequence>
  <decisionTable>
    <module>DecisionConditions</module>
    <orderby>sequence</orderby>  <!-- column to order the records by -->
    <searches>
      <search>
        <condition>
          <input>season</input>  <!-- context variable name -->
          <operation>e</operation>  <!-- QueryGenerator operators -->
          <field>season</field>  <!-- fieldname of module -->
        </condition>
        <condition>
          <input>guestcount</input>  <!-- context variable name -->
          <operation>le</operation>  <!-- QueryGenerator operators -->
          <field>guestcount</field>  <!-- fieldname of module -->
        </condition>
      </search>
    </searches>
    <output>desireddish</output>  <!-- fieldname -->
  </decisionTable>
  <output>FieldValue</output>
</rule>
</rules>
</decision>

In this case, I am playing with the Hit Policy which has changed to First, so now my users must understand that the ranges are defined from the previous value to the one defined in each record and that sequence is VERY important.

Since, in the end, the supported operations are those of the Query Generator, which even supports ranges:

QueryGenerator->addConditions(column, operator, values) 

where operator can be '[]', '[[', ']]', '][' among many others

the possibilities that the implementor has are very big.

A decision map that would return the value of a global variable would look something like the map below. The context would have to send in all the role and group of the current user and I'm not totally sure if the “module list” would work as it is below, but it will be VERY close and enough for you to get an idea of how this map works.

<decision>
<hitPolicy>F</hitPolicy>
<rules>
<rule>
  <sequence>1</sequence>
  <decisionTable>
    <module>GlobalVariable</module>
    <searches>
      <search> <!-- Mandatory GV -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>checkboxtrue</input>  <!-- checkboxtrue == 1 in context -->
          <operation>e</operation>
          <field>mandatory</field>
        </condition>
      </search>
      <search> <!-- In module for user -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>userid</input>
          <operation>e</operation>
          <field>assigned_user_id</field>
        </condition>
        <condition>
          <input>checkboxtrue</input>  <!-- checkboxtrue == 1 in context -->
          <operation>e</operation>
          <field>inmodulelist</field>
        </condition>
        <condition>
          <input>gvmodule</input>
          <operation>c</operation>
          <field>gvmodule</field>
        </condition>
      </search>
      <search> <!-- In module for group -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>groupid</input>
          <operation>e</operation>
          <field>assigned_user_id</field>
        </condition>
        <condition>
          <input>checkboxtrue</input>  <!-- checkboxtrue == 1 in context -->
          <operation>e</operation>
          <field>inmodulelist</field>
        </condition>
        <condition>
          <input>gvmodule</input>
          <operation>c</operation>
          <field>gvmodule</field>
        </condition>
      </search>
      <search> <!-- In module for role -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>userrole</input>
          <operation>c</operation>
          <field>gvrole</field>
        </condition>
        <condition>
          <input>checkboxtrue</input>  <!-- checkboxtrue == 1 in context -->
          <operation>e</operation>
          <field>inmodulelist</field>
        </condition>
        <condition>
          <input>gvmodule</input>
          <operation>c</operation>
          <field>gvmodule</field>
        </condition>
      </search>
      <search> <!-- without module for user -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>userid</input>
          <operation>e</operation>
          <field>assigned_user_id</field>
        </condition>
        <condition>
          <input>checkboxfalse</input>  <!-- checkboxfalse == 0 in context -->
          <operation>e</operation>
          <field>inmodulelist</field>
        </condition>
      </search>
      <search> <!-- without module for group -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>groupid</input>
          <operation>e</operation>
          <field>assigned_user_id</field>
        </condition>
        <condition>
          <input>checkboxfalse</input>  <!-- checkboxfalse == 1 in context -->
          <operation>e</operation>
          <field>inmodulelist</field>
        </condition>
      </search>
      <search> <!-- without module for role -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>userrole</input>
          <operation>c</operation>
          <field>gvrole</field>
        </condition>
        <condition>
          <input>checkboxfalse</input>  <!-- checkboxfalse == 1 in context -->
          <operation>e</operation>
          <field>inmodulelist</field>
        </condition>
      </search>
      <search> <!-- Default GV -->
        <condition>
          <input>gvname</input>
          <operation>e</operation>
          <field>gvname</field>
        </condition>
        <condition>
          <input>checkboxtrue</input>  <!-- checkboxtrue == 1 in context -->
          <operation>e</operation>
          <field>default</field>
        </condition>
      </search>
    </searches>
    <output>value</output>  <!-- fieldname -->
  </decisionTable>
  <output>FieldValue</output>
</rule>
</rules>
</decision>