Rules

Rules change matching traffic as it passes through Reqly. Open them with Rules › Show Rules (⌥⌘R).

The Rules window’s sidebar lists the kinds of rules: Breakpoints, Map Local, Map Remote, Rewrite, Block, Scripts and Slow Network. Each kind has a switch at the top of its pane and in the Rules menu, and each rule has a switch of its own. A rule acts only when both are on. A green dot in the sidebar shows the kinds that are on.

Rules act on requests that start after you change them.

Add a rule

• In the Rules window, select a kind and click +.
• Or right-click a request in the list, and choose Add Rule, then a kind. The rule starts out with the request’s host, path and method.

Saving a new rule turns its kind on. As you edit a rule, it says how many of the requests captured so far it matches.

Double-click a rule to edit it. Right-click it to Duplicate, Move Up, Move Down or Delete it. To remove a rule, you can also select it and press Delete.

Which requests a rule matches

A rule matches a Host, a Path and a Method. Leave a field empty to match anything.

• * matches anything, or nothing: /v2/* matches /v2/forecast and /v2/forecast/hourly.
• *.example.com matches the subdomains of example.com, but not example.com itself.
• Hosts match in any case. Paths match case exactly.
• A path matches without the query, unless the pattern has a ? in it. So /v2/forecast matches /v2/forecast?city=amsterdam, and /v2/forecast?city=* matches only requests with a city.
• To match one port, add it to the host: localhost:8080.
• A rule matches both http and https.

Rules match the request as the app sent it. They act on requests you send from Reqly too. Of an encrypted connection, which Reqly doesn’t decrypt, only the host is known, so only a Block rule for any path acts on it.

Breakpoints

A breakpoint pauses a matching request, its response, or both, so you can change it before it goes on. Turn breakpoints on with the Breakpoints switch in the toolbar, or with Rules › Breakpoints (⇧⌘B).

Something that’s paused shows as Paused in the list, and its details become an editor:

• A request: its method, URL, headers and body.
• A response: its status, reason, headers and body.

Then click Continue (⌘↩) to send it on, or Cancel Request (Cancel Response for a response) to stop it, and the app gets a 502 error. Rules › Continue All Paused Requests (⌥⌘↩) sends everything that’s paused on, unchanged.

A pause lasts until you decide. Reqly lays out JSON bodies for editing, and sets Content-Length from the body.

Map Local

Answers matching requests with a file on your Mac. The server never sees them.

• File: click Choose… to pick it. Reqly reads it for every request, so changing the file changes the answer.
• Status: 200 to begin with.
• Content type: from the file’s extension, unless you enter one.

When you add the rule from a request, Save the Response as a File… saves that request’s response, ready to edit.

Map Remote

Sends matching requests to another server, such as staging instead of production. Enter the server in Send to, such as https://staging.example.com. A path there replaces the request’s path, and the query stays.

The request in the list stays the way the app sent it. Its Overview says where it went.

Rewrite

Changes matching traffic as it passes. Click Add Change for each change:

• Set Header and Remove Header, in the request or the response.
• Set Query Parameter and Remove Query Parameter, in the request.
• Replace Body Text, in the request or the response. It replaces every match, and matches case exactly.
• Set Status, in the response.

Block

Stops matching requests, so the server never sees them: With a status (403 to begin with), or By closing the connection, as a failing network would. For a host Reqly doesn’t decrypt, a Block rule for any path blocks the whole host.

Scripts

JavaScript that changes requests and responses as they pass, or answers requests itself. See Scripts.

Slow network

Slows traffic down to the speed of a slower network, to see how apps cope. Turn it on with the Slow Network switch in the toolbar, or with Rules › Slow Network (⇧⌘T).

Choose a Profile:

Profile	Download	Upload	Latency	Packet loss
3G	780 kbit/s	330 kbit/s	100 ms	None
LTE	12,000 kbit/s	4,000 kbit/s	50 ms	None
Lossy	1,000 kbit/s	1,000 kbit/s	300 ms	5%

Or set Download, Upload, Latency and Packet loss yourself, which makes the profile Custom. Under Hosts, list the hosts to slow down. With none listed, every host is slowed down. Changes apply to new connections.

When several rules match

• Breakpoints, Map Local, Map Remote and Block: the first matching rule in the list acts. A Block rule acts before Map Local.
• Rewrite and Scripts: every matching rule acts, in the order of the list.

Kinds act in this order. Block and Map Local answer first, and if one does, nothing else acts. Otherwise: Map Remote, then the request’s rewrites, scripts and breakpoint, then the server, then the response’s rewrites, scripts and breakpoint.

Each rule that acted is listed under Rules in the request’s Overview.