Rule

Paid Feature

A Rule describes whether and how to modify a flow on the fly. To create a rule, move the mouse onto the “Rule” header in the sidebar and click the add button.

Different kinds of rules has different editors for the options, while most of them share a similar filter editor that tells the rule what kind of flows need to be modified.

List of Rules

Affected Flows

Rules remember which flows they have affected and display the numbers on the right side of the sidebar, just like filters. Selecting rules in the siderbar also works like selecting filters: only flows that have been affected by any of the selected rules will be listed.

The rule’s filter doesn’t sufficiently indicate whether a flow will be affected

A rule may also consult its options to decide whether a flow needs to be modified.
For example, a URL Rewrite rule that replaces a keyword in the URL, does not modify a flow if no occurrences of the keyword are found in the URL, even if the rule’s filter matches the flow.

Execution Order

Rules listed in the sidebar are draggable. The order of rules is the order of executions.

Say, we have 4 rules listed in this order:

  1. a URL Rewrite rule that rewrites URLs in requests,
  2. a Scripting rule that does changes to both requests and responses,
  3. a Header Modification rule that modifies request headers,
  4. a Body Modification rule that modifies response bodies.

The sequence diagram below shows how they will be executed: Rule Timing