HTTPRoute resources can issue redirects to clients or rewrite paths sent upstream using filters. This guide shows how to use these features.
Note that redirect and rewrite filters are mutually incompatible. Rules cannot use both filter types at once.
Redirects return HTTP 3XX responses to a client, instructing it to retrieve a
different resource. RequestRedirect rule
filters
instruct Gateways to emit a redirect response to requests matching a filtered
HTTPRoute rule.
Redirect filters can substitute various URL components independently. For
example, to issue a permanent redirect (301) from HTTP to HTTPS, configure
requestRedirect.statusCode=301 and requestRedirect.scheme="https":
{% include 'standard/http-redirect-rewrite/httproute-redirect-http.yaml' %}Redirects change configured URL components to match the redirect configuration
while preserving other components from the original request URL. In this
example, the request GET http://redirect.example/cinnamon will result in a
301 response with a location: https://redirect.example/cinnamon header. The
hostname (redirect.example), path (/cinnamon), and port (implicit) remain
unchanged.
To redirect HTTP traffic to HTTPS, you need to have a Gateway with both HTTP and HTTPS listeners.
{% include 'standard/http-redirect-rewrite/gateway-redirect-http-https.yaml' %}There are multiple ways to secure a Gateway. In this example, it is secured
using a Kubernetes Secret(redirect-example in the certificateRefs section).
You need a HTTPRoute that attaches to the HTTP listener and does the redirect
to HTTPS. Here we set sectionName to be http so it only selects the
listener named http.
{% include 'standard/http-redirect-rewrite/httproute-redirect-http.yaml' %}You also need a HTTPRoute that attaches to the HTTPS listener that forwards HTTPS traffic to application backends.
{% include 'standard/http-redirect-rewrite/httproute-redirect-https.yaml' %}Path redirects use an HTTP Path Modifier to replace either entire paths or path
prefixes. For example, the HTTPRoute below will issue a 302 redirect to all
redirect.example requests whose path begins with /cayenne to /paprika:
{% include 'standard/http-redirect-rewrite/httproute-redirect-full.yaml' %}Both requests to
https://redirect.example/cayenne/pinch and
https://redirect.example/cayenne/teaspoon will receive a redirect with a
location: https://redirect.example/paprika.
The other path redirect type, ReplacePrefixMatch, replaces only the path
portion matching matches.path.value. Changing the filter in the above to:
{% include 'standard/http-redirect-rewrite/httproute-redirect-prefix.yaml' %}will result in redirects with location: https://redirect.example/paprika/pinch and location: https://redirect.example/paprika/teaspoon response headers.
Rewrites modify components of a client request before proxying it upstream. A
URLRewrite
filter
can change the upstream request hostname and/or path. For example, the
following HTTPRoute will accept a request for
https://rewrite.example/cardamom and send it upstream to example-svc with
host: elsewhere.example in request headers instead of host: rewrite.example.
{% include 'standard/http-redirect-rewrite/httproute-rewrite.yaml' %}Path rewrites also make use of HTTP Path Modifiers. The HTTPRoute below
will take request for https://rewrite.example/cardamom/smidgen and proxy a
request to https://elsewhere.example/fennel upstream to example-svc.
{% include 'standard/http-redirect-rewrite/httproute-rewrite-full-path.yaml' %}Instead using type: ReplacePrefixMatch and replacePrefixMatch: /fennel will
request https://elsewhere.example/fennel/smidgen upstream.
{% include 'standard/http-redirect-rewrite/httproute-rewrite-prefix-path.yaml' %}