How the Expression Builder works
For detailed information about SIP Message Manipulation, see SIP Message Manipulation.
Through the Condition Expression Builder, you can add a Condition Expression to a Message Rule Table. The Expression Builder allows you to combine multiple Condition Rules in a set of expressions (or a single expression) in order to determine whether a rule is executed.
The configured expressions may be nested (maximum nesting level of 3). For example, you can apply Condition1 OR Condition3; the system evaluates the nested OR expression before the outer AND expression.
Adding Condition Expression to a Message Rule Table
These instructions assume the Message Rule Table has been previously created. For more information about creating a table, see Managing Message Rule Tables.
To add a condition expression to a message rule:
- In the WebUI, click the Settings tab.
- In the left navigation pane, select SIP > Message Manipulation > Message Rule Table. Click the desired Message Rule Table.
In the Settings tab, click the expand ( ) icon next to the entry in which you want to add a Condition Expression.
In the Condition Expression field, click Add/Edit.
From the drop down box, select an option: Match All Conditions, Match Any Condition, or Always Match.See below for details.
Match Drop Down List Option
Match Any Conditions
Expression is matched to any conditions that are considered "true"; the condition rule executes if any of the selected condition rules are the outermost nesting level are true.
Match All Conditions
Expression is matched to any conditions that are considered "true"; the condition rule executes only if all the selected condition rules at the outermost nesting level are true.
Expression is unconditional; the condition rule is always matched. When Always Match is selected, Condition Rule options are not visible.
- Click Apply. For Match Any Conditions or Match All Conditions options, a conditions expression drop down box is displayed. (For Always Match, your are returned to the Condition Expression field).
Select the desired condition for that rule (this drop down box is generated from the Conditions configured in the Condition Rule Table). See Creating and Modifying Condition Rules.
Select subsequent condition rules (if applicable). See below for how to use the window options.
You can add up the 3 nesting levels for each condition, for an aggregate total of 10 rows.
How to Use
Condition Drop down Box
Select expression from the drop down box.The options are derived from the entries in the Condition Rule Table. See Managing Condition Rule Tables. For each additional condition selected, the Match All/Any Condition drop down is displayed.
Adds a new condition rule directly beneath the current row. A maximum of 10 rows is supported. This icon is disabled when the maximum of 10 rows is reached.
Deletes the selected condition rule or Match All/Any Condition. If a Match All/Any condition is selected, all condition rules within that group are also removed. This icon is disabled for condition rule rows which are the only member of a Match All/Any group. Click the "X" at the group level to remove the entire group.
Adds a group directly underneath the current row, and also adds one condition rule row to that group. This icon is disabled for any rows which are at the deepest-allowed nesting level.