HTTP Rules

HTTP rules match properties of an HTTP request: the User-Agent header and the request URL. They only take effect for requests processed by Surge's HTTP engine; plain TCP or UDP connections are never matched by these rules.

[Rule]
USER-AGENT,Instagram*,Proxy
URL-REGEX,^http://example\.com/api/,DIRECT

When HTTP Rules Apply

A request is visible to HTTP rules only when the HTTP engine handles it and the relevant property is available:

• Plain HTTP requests handled by the HTTP engine expose both the URL and the User-Agent header. This includes requests sent to Surge's HTTP proxy port and TCP connections forced into HTTP processing with force-http-engine-hosts.
• HTTPS requests expose their full URL and headers only when MITM decryption is enabled for the hostname.
• For HTTPS requests that are not decrypted, no URL is available, so URL-REGEX cannot match. USER-AGENT can only match if the client happens to send a User-Agent header in the proxy CONNECT request.

See HTTP Processing Overview for how traffic reaches the HTTP engine.

Rule Types

USER-AGENT

USER-AGENT,Instagram*,DIRECT

Matches if the User-Agent header of the request matches the value. Wildcard characters * and ? are supported. Matching is case-sensitive.

URL-REGEX

URL-REGEX,^http://google\.com,DIRECT

Matches if the complete request URL matches the regular expression. The rule matches when the pattern is found anywhere in the URL; anchor with ^ when you want a prefix match. The regular expression is case-sensitive.

For plain HTTP requests the tested string is the full URL, e.g. http://example.com/path?query. For HTTPS requests with MITM enabled, it is the decrypted URL, e.g. https://example.com/path?query.

If the value contains commas, wrap it in double quotes:

URL-REGEX,"^http://example\.com/(a|b),?c",Proxy

extended-matching

You can append the extended-matching parameter to also test URL variants in which the host part is replaced by the TLS SNI and by the HTTP Host header (or :authority), which helps when the request targets an IP address or the Host differs from the URL host:

URL-REGEX,^https://example\.com,Proxy,extended-matching