There are simple rewrites (fast) and complex rewrites (slower), but they’re powerful enough to accommodate most dynamic back-end applications.

• not if specified, will invert the pattern and matching logic
• from is a regular expression to match

Advanced users may open a block and make a complex rewrite rule:

rewrite [*basepath*] { regexp *pattern* ext *extensions...* if *a cond b* if_op *[*and|or*]* to *destinations...* }

• basepath is the base path to match before rewriting with regular expression. Default is /.
• regexp (shorthand: r) will match the path with the given regular expression pattern. Extremely high-load servers should avoid using regular expressions.
• extensions… is a space-separated list of file extensions (prepended with a dot) to include or ignore. Prefix an extension with ! to exclude an extension. The forward slash / symbol matches paths without file extensions.
• if specifies a rewrite condition. Multiple ifs are AND-ed together. a and b are any string and may use . cond is the condition, with possible values explained below.
• if_op specifies how the ifs are evaluated; the default is and.
• destinations… is one or more space-separated paths to rewrite to, with support for request placeholders as well as numbered regular expression captures such as {1}, {2}, etc. Rewrite will check each destination in order and rewrite to the first destination that exists. Each one is checked as a file or, if ends with /, as a directory. The last destination will act as default if no other destination exists.

The if keyword is a powerful way to describe your rule. It takes the format a cond b, where the values a and b are separated by cond, a condition. The condition can be any of these:

• is = a equals b
• has = a has b as a substring (b is a substring of a)
• not_has = b is NOT a substring of a
• starts_with = b is a prefix of a
• not_starts_with = b is NOT a prefix of a
• ends_with = b is a suffix of a
• not_ends_with = b is NOT a suffix of a
• match = a matches b, where b is a regular expression

Note: As a general rule, you can negate any condition cond by prefixing it with .

rewrite .* /index.php

When requests come in for /mobile, actually serve /mobile/index.

rewrite /mobile /mobile/index

If the file is not favicon.ico and it is not a valid file or directory, serve the maintenance page if present, or finally, rewrite to index.php.

rewrite { if {file} not favicon.ico to {path} {path}/ /maintenance.html /index.php }

If user agent includes “mobile” and path is not a valid file/directory, rewrite to the mobile index page.

Rewrite /app to /index with a query string. {1} is the matched group (.*).

rewrite /app { r (.*) to /index?path={1} }

Rewrite requests for /app/example to /index.php?category=example.

rewrite /app { r ^/(\w+)/?$ to /index?category={1} }

Join us in the , where the open source community gathers to share their knowledge.

Purchase a commercial license to use Caddy with your business and for basic email support, along with other benefits!