How to Guides

Advanced Path Matching

By default, path matching in Zuplo uses the OpenAPI slug format, e.g. /pizza/{size} where size would be a URL parameter, with the value passed into the runtime as request.params.size property.

However, you can opt to use a more advanced path matching approach based on the web standard URLPattern.

The most basic path is / which will simple match the root path. You can add other static paths like /foo and /foo/bar


Use to test your URL Patterns in the browser.

Trailing Slashes#

In URLPattern, trailing slashes are not accepted unless explicitly specified. For example:

  • /cars/:manufacturer

Would match /cars/ford but not /cars/ford/. If you want to support this you must add a little regex to the end of your path, e.g.

  • /cars/:manufacturer{/}?

Will match both example routes given above.

Dynamic Paths#

URLPattern supports dynamic matching including a feature that will parameterize parts of the URL. For example:

Path: /products/:productId/sizes/:size will match the following paths

/products/pizza/size/small and set the params object on request to:

{ "productId": "pizza", "size": "small" }


Query-strings (or search parameters) will not affect path matching.

Regular Expressions and Wildcards#

You can also use regular expressions in your paths. They must be contained in ().


Path /(.*) will match anything.


This is a true wildcard route and can be used for custom 404s by making this the last route in your OpenAPI file (and matching all methods).

Path /(a?b) will match either /ab or /b.

Path /main/(a|b) will match /main/a or /main/b.

Path /icon-(\d++).png will match /icon-1234.png or any other series of digits for 1234.

Named groups#

You can also name your regexp groups so that they appear as named parameters.

name:(.*) - will match a wildcard and call the parameter.

For example, the path products/:productId/icons/icon-:imageIndex(\d+).png will match /products/pizza/icons/icon-2.png and produce a request.params object as follows:

{ "productId": "pizza", "imageIndex": "2" }

You can write a URL Rewrite that takes an incoming wildcard and appends it to the backend request, e.g.

Path: /foo/bar:path(/.*) Incoming URL: /foo/bar/apple/banana URL Rewrite Pattern:${params.path} Outgoing URL:

Not supported#

Note that not all regex features are available, us of the following will either be ignored or result in an error, including

  • (?:...) - named matches
  • ^ or $ - start or end of string
  • [abc] - character classes
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