refactor: drop proxy-supports-routes capability trigger

The trigger was added to refuse proxy:route:set under openresty and haproxy, but the hard refusal created an ordering dependency for declarative tools and blocked users from staging routes ahead of a backend switch. Routes are now stored regardless of the active backend and silently ignored by backends that do not render them; the docs call out the inert behavior under openresty and haproxy.

docs/development/plugin-triggers.md

@@ -2390,27 +2390,6 @@ while IFS='|' read -r proc port path strip; do
 done < <(plugn trigger proxy-routes-list "$APP")
 ```
 
-### `proxy-supports-routes`
-
-- Description: Returns `true` if the proxy backend currently selected for the app supports path-based routes (`proxy:route:set`), `false` otherwise. Implemented by each in-tree proxy plugin (nginx, traefik, caddy, and k3s return `true`; openresty and haproxy return `false`). The `proxy:route:set` command calls this trigger and refuses with a "not supported" message when the result is `false`.
-- Invoked by: `proxy:route:set` in the `proxy` plugin
-- Arguments: `$APP`
-- Example:
-
-```shell
-#!/usr/bin/env bash
-
-set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
-
-APP="$1"
-
-if [[ "$(plugn trigger proxy-type "$APP")" != "my-proxy" ]]; then
-  return
-fi
-
-echo "true"
-```
-
 ### `proxy-type`
 
 - Description: Returns the proxy type for an app

docs/networking/proxy-management.md

@@ -196,7 +196,7 @@ See the [port management documentation](/docs/networking/port-management.md) for
 By default, every HTTP/HTTPS request is routed to the `web` process declared in the app's `Procfile`. Use `proxy:route:*` to route specific path prefixes to a different process within the same app - for example, sending `/api/v0/*` to an `api` process or `/ws` to a `websocket` process. The `web` process always handles every other path as an implicit catch-all.
 
 > [!NOTE]
-> Path-based routing is supported by the `nginx`, `traefik`, `caddy`, and `k3s` proxy backends. The `openresty` and `haproxy` backends do not currently support it; `proxy:route:set` exits with a "not supported" message under those backends. Support is tracked in [dokku/openresty-docker-proxy#137](https://github.com/dokku/openresty-docker-proxy/issues/137) and the `haproxy-vhosts` sidecar.
+> Path-based routing is rendered by the `nginx`, `traefik`, `caddy`, and `k3s` proxy backends. The `openresty` and `haproxy` backends accept and store route declarations, but the routes are inert (no labels are emitted) because the sidecar images do not yet support path-prefix vocabulary. Routes stored ahead of a backend switch will activate automatically once the proxy is changed to a rendering backend. Tracked at [dokku/openresty-docker-proxy#137](https://github.com/dokku/openresty-docker-proxy/issues/137) and the `haproxy-vhosts` sidecar.
 
 #### Adding a route
 
@@ -273,6 +273,7 @@ dokku proxy:route:set node-js-app api /api/v0/admin
 - **nginx**: route changes take effect immediately on the next `proxy-build-config` reload (which `proxy:route:*` invokes automatically).
 - **traefik** and **caddy**: routes are applied via Docker labels on the target containers. Containers must be recreated for new or removed labels to take effect. The command prints a notice instructing you to run `dokku ps:rebuild <app>` to recreate containers.
 - **k3s**: route changes take effect on the next deploy when the chart is re-rendered.
+- **openresty** and **haproxy**: routes are stored but inert under these backends. They activate automatically if you switch to a rendering backend (`nginx`, `traefik`, `caddy`, or `k3s`).
 - **WebSocket** traffic is forwarded transparently on `nginx`, `traefik`, `caddy`, and `k3s` backends - no additional configuration is required.
 - A route to a process that is scaled to `0` will resolve to no upstream until the process is scaled up (`dokku ps:scale <app> <process>=1`). `proxy:route:set` warns when this is the case.
 

plugins/caddy-vhosts/proxy-supports-routes

@@ -1,18 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail
-[[ $DOKKU_TRACE ]] && set -x
-source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
-
-trigger-caddy-vhosts-proxy-supports-routes() {
-  declare desc="advertises path-based routing support for caddy"
-  declare trigger="proxy-supports-routes"
-  declare APP="$1"
-
-  if [[ "$(plugn trigger proxy-type "$APP")" != "caddy" ]]; then
-    return
-  fi
-
-  echo "true"
-}
-
-trigger-caddy-vhosts-proxy-supports-routes "$@"

plugins/haproxy-vhosts/proxy-supports-routes

@@ -1,21 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail
-[[ $DOKKU_TRACE ]] && set -x
-source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
-
-trigger-haproxy-vhosts-proxy-supports-routes() {
-  declare desc="advertises path-based routing support for haproxy (currently false)"
-  declare trigger="proxy-supports-routes"
-  declare APP="$1"
-
-  if [[ "$(plugn trigger proxy-type "$APP")" != "haproxy" ]]; then
-    return
-  fi
-
-  # The byjg/easy-haproxy sidecar image only supports host-based routing.
-  # Path-prefix routing requires either an upstream change to that sidecar
-  # or a different config-generation strategy.
-  echo "false"
-}
-
-trigger-haproxy-vhosts-proxy-supports-routes "$@"

plugins/nginx-vhosts/proxy-supports-routes

@@ -1,18 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail
-[[ $DOKKU_TRACE ]] && set -x
-source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
-
-trigger-nginx-vhosts-proxy-supports-routes() {
-  declare desc="advertises path-based routing support for nginx"
-  declare trigger="proxy-supports-routes"
-  declare APP="$1"
-
-  if [[ "$(plugn trigger proxy-type "$APP")" != "nginx" ]]; then
-    return
-  fi
-
-  echo "true"
-}
-
-trigger-nginx-vhosts-proxy-supports-routes "$@"

plugins/openresty-vhosts/proxy-supports-routes

@@ -1,20 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail
-[[ $DOKKU_TRACE ]] && set -x
-source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
-
-trigger-openresty-vhosts-proxy-supports-routes() {
-  declare desc="advertises path-based routing support for openresty (currently false)"
-  declare trigger="proxy-supports-routes"
-  declare APP="$1"
-
-  if [[ "$(plugn trigger proxy-type "$APP")" != "openresty" ]]; then
-    return
-  fi
-
-  # The openresty sidecar image does not yet accept path-prefix routing labels.
-  # Tracked upstream at dokku/openresty-docker-proxy#137.
-  echo "false"
-}
-
-trigger-openresty-vhosts-proxy-supports-routes "$@"

plugins/proxy/route_subcommands.go

@@ -23,15 +23,6 @@ func CommandRouteSet(appName string, processName string, path string, port int,
 		return errors.New("Usage: dokku proxy:route:set <app> <process> <path> [--port <port>] [--strip-prefix]")
 	}
 
-	supported, err := SupportsRoutes(appName)
-	if err != nil {
-		return err
-	}
-	if !supported {
-		proxyType := getComputedProxyType(appName)
-		return fmt.Errorf("path-based routing is not yet supported with the %s proxy backend", proxyType)
-	}
-
 	if port == 0 {
 		port = DefaultRoutePort
 	}

plugins/proxy/routes.go

@@ -171,21 +171,6 @@ func RoutedProcessTypes(appName string) ([]string, error) {
 	return out, nil
 }
 
-// SupportsRoutes returns true if the proxy backend selected for the app
-// supports path-based routing, as declared by the proxy-supports-routes
-// trigger. Backends that do not implement the trigger are treated as not
-// supporting routes (conservative default).
-func SupportsRoutes(appName string) (bool, error) {
-	result, err := common.CallPlugnTrigger(common.PlugnTriggerInput{
-		Trigger: "proxy-supports-routes",
-		Args:    []string{appName},
-	})
-	if err != nil {
-		return false, err
-	}
-	return result.StdoutContents() == "true", nil
-}
-
 // AddRoute upserts a route. Returns whether the stored state changed.
 func AddRoute(appName string, route Route) (bool, error) {
 	if err := ValidatePath(route.Path); err != nil {

plugins/scheduler-k3s/proxy-supports-routes

@@ -1,18 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail
-[[ $DOKKU_TRACE ]] && set -x
-source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
-
-trigger-scheduler-k3s-proxy-supports-routes() {
-  declare desc="advertises path-based routing support for k3s"
-  declare trigger="proxy-supports-routes"
-  declare APP="$1"
-
-  if [[ "$(plugn trigger proxy-type "$APP")" != "k3s" ]]; then
-    return
-  fi
-
-  echo "true"
-}
-
-trigger-scheduler-k3s-proxy-supports-routes "$@"

plugins/traefik-vhosts/proxy-supports-routes

@@ -1,18 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail
-[[ $DOKKU_TRACE ]] && set -x
-source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
-
-trigger-traefik-vhosts-proxy-supports-routes() {
-  declare desc="advertises path-based routing support for traefik"
-  declare trigger="proxy-supports-routes"
-  declare APP="$1"
-
-  if [[ "$(plugn trigger proxy-type "$APP")" != "traefik" ]]; then
-    return
-  fi
-
-  echo "true"
-}
-
-trigger-traefik-vhosts-proxy-supports-routes "$@"

tests/unit/proxy-route.bats

@@ -218,32 +218,30 @@ teardown() {
   assert_output "true"
 }
 
-@test "(proxy:route:set) refuses under openresty backend" {
+@test "(proxy:route:set) stores routes under openresty backend even though they are inert" {
   dokku proxy:set "$TEST_APP" openresty >/dev/null 2>&1 || skip "openresty proxy not available"
 
   run /bin/bash -c "dokku proxy:route:set $TEST_APP api /api/v0"
   echo "output: $output"
   echo "status: $status"
-  assert_failure
-  assert_output_contains "not yet supported"
+  assert_success
 
   run /bin/bash -c "dokku proxy:route:report $TEST_APP"
   echo "output: $output"
   echo "status: $status"
-  assert_output_contains "(none)"
+  assert_output_contains "/api/v0 -> api:5000"
 }
 
-@test "(proxy:route:set) refuses under haproxy backend" {
+@test "(proxy:route:set) stores routes under haproxy backend even though they are inert" {
   dokku proxy:set "$TEST_APP" haproxy >/dev/null 2>&1 || skip "haproxy proxy not available"
 
   run /bin/bash -c "dokku proxy:route:set $TEST_APP api /api/v0"
   echo "output: $output"
   echo "status: $status"
-  assert_failure
-  assert_output_contains "not yet supported"
+  assert_success
 
   run /bin/bash -c "dokku proxy:route:report $TEST_APP"
   echo "output: $output"
   echo "status: $status"
-  assert_output_contains "(none)"
+  assert_output_contains "/api/v0 -> api:5000"
 }