Configuring rules define conditions based on which it is possible to determine whether a policy has to be executed or not at runtime.

For example, an XML to JSON policy can be applied only if the Accept Header is set as application/json.

The Add/Edit Rule button at the lower-right part of each Policy Configuration page allows the API author to add additional rules to a policy before a message is passed to a policy.

A sample snapshot of the Monetization Limit Check Policy Configuration page is provided below.

Figure 1: A sample Policy Configuration page with the Add/Edit Rule button

Adding Rule

Click the Add/Edit Rule  button to start configuring a rule.

Figure 2: Add/Edit Rule dialog box to configure rules

Adding a statement

To add a statement, perform the following actions in the Update Rule dialog box

1. Click the Down  arrow
2. Click the New statement option.
   
   
   Figure 3: Navigating to add new statement
   
   

3. Click the Edit Statement  button. Edit the rule by changing the properties present in the dialog box. 

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   Each property in the dialog box is explained in the table after the steps.

   
   Figure 3: "Add new statement" option to add more rules
   
   

4. Click OK and then click the Save button on top of the screen to apply the changes.
   
   
   
   

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   The Preview option helps in cross-verifying whether or not the rule is defined as intended.

Rule parameters

Operator options

Choose the operator from the options below to form a condition.

Equals

Compares two strings and returns true if the strings are the same and false if not.

Not Equals

Compares two strings and returns true if the strings are not the same and else false. 

Like

Matches whole string or substring in a string. Use wildcard characters to match the substring.

Not Like

The whole string or substring should not be present in a string. Use wildcard characters to match the substring.

One of

Matches any one string added using commma-seperated values and returns true, otherwise false.

Not one of

Not matching any string added using comma-separated values return true, otherwise false. 

Adding more statements

For using conditional statements using conjunctions in the rule, add the conjunction (OR/AND) that needs to be used between the statements and then add those statements.

1. Click the Down  arrow in the Update Rule section
2. Click any one of the following:
   1. add conjunction
   2. or conjunction
      
      
   
   
   

3. Follow the steps in the Adding a statement section.
   

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   Click the Edit button to edit the statements added.