fix(coder-routes): stop distinct web_extra_exposed_ports from clobbering each other's route

Any two web_extra_exposed_ports entries on the "web" service (e.g.
ddev-playwright's playwright:9323 and a VNC add-on's kasmvnc:8444) reduced
to the same svc_name="web" in the dynamic add-on branch, so both computed
the identical ROUTER_NAME and whichever was processed last silently
overwrote the other's Traefik route. Key the fallback slug on service AND
port so distinct ports never collide.

Also generalize docker-compose.coder-describe.yaml generation: rather than
hardcoding "xhgui"/"adminer" in coder-setup, coder-routes now derives a
describe-url-port override for every real compose service it discovers
while building routes (not just two hardcoded names), so any current or
future add-on/custom service with its own router gets a correct Coder URL
in `ddev describe`/`ddev launch` automatically. coder-setup keeps only a
minimal bootstrap covering the primary web+Mailpit URLs, since those are
the only ones computable before a project has ever been started.

This cannot fix web_extra_exposed_ports rows themselves (playwright,
kasmvnc, etc.) — verified against ddev/ddev source that
cmd/ddev/cmd/describe.go's WebExtraExposedPorts stanza always builds that
row's URL itself and never reads describe-url-port. That needs a separate
upstream feature request against ddev/ddev.

Validated live in a running Coder sandbox: both routes now coexist
(randyfay-coder-web-9323, randyfay-coder-web-8444), and xhgui's `ddev
describe` row picked up its Coder URL after one restart.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Author: rfay

image/scripts/.ddev/commands/host/coder-routes

@@ -61,6 +61,24 @@ yq e -i \
 
 echo "Building Coder Traefik routes from ${DDEV_PROJECT}_merged.yaml:"
 
+# Collected alongside the Traefik routes below, then written once at the end into
+# .ddev/docker-compose.coder-describe.yaml so 'ddev describe'/'ddev launch' show
+# the same Coder URL every router here actually resolves to. WEB_URL/MAILPIT_URL
+# hold the primary site (svc_name="web" is special-cased out of DESCRIBE_URLS
+# below, since both the primary site and Mailpit share that service name but need
+# their own describe-url-port entries: web's own row, and its "Mailpit: ..." line).
+# DESCRIBE_URLS covers every OTHER real service this project's router config
+# defines — xhgui, adminer, or any future/custom add-on service that gets its own
+# router — generically, with no per-name special-casing. It intentionally excludes
+# web_extra_exposed_ports entries (ddev-playwright's "playwright" row, a VNC
+# add-on's "kasmvnc" row, etc.): those aren't separate compose services, they're
+# extra ports on the "web" service itself, and DDEV's describe-url-port extension
+# is only ever read per compose service name — see the longer explanation in
+# coder-setup.
+WEB_URL=""
+MAILPIT_URL=""
+declare -A DESCRIBE_URLS
+
 # Iterate over every router in the merged config.
 # Each entry has an entrypoints list and a service name like {project}-{svc}-{port}.
 while IFS= read -r router; do
@@ -108,7 +126,17 @@ while IFS= read -r router; do
   elif [ "$svc_name" = "adminer" ]; then
     slug="adminer-${PROJECT_SLUG}"
   else
-    slug="$svc_name"
+    # Dynamic add-on branch (below): a project can define more than one
+    # web_extra_exposed_ports entry (e.g. ddev-playwright's "playwright" port
+    # and a VNC add-on's "kasmvnc" port). Both live on the docker-compose "web"
+    # service, so svc_name is "web" for all of them — slug="$svc_name" alone
+    # would give them the identical ROUTER_NAME and each would silently
+    # clobber whichever was processed before it (same failure mode as the
+    # primary-web collision described above, just between two non-primary
+    # ports instead of with the primary). Including the port keeps every
+    # add-on port's route distinct. The printed URL already disambiguates by
+    # ext_port (below); only this map key needs the same treatment.
+    slug="${svc_name}-${port}"
   fi
 
   ROUTER_NAME="${DDEV_PROJECT}-coder-${slug}"
@@ -135,7 +163,8 @@ while IFS= read -r router; do
          .http.routers.\"${ROUTER_NAME}\".middlewares = [env(MW)] |
          .http.routers.\"${ROUTER_NAME}\".tls = false" \
       /tmp/coder-routes-raw.yaml
-    echo "  + ${slug}: ${entrypoints[*]} → ${service}  (https://${CODER_HOST})"
+    WEB_URL="https://${CODER_HOST}"
+    echo "  + ${slug}: ${entrypoints[*]} → ${service}  (${WEB_URL})"
   elif [ "$slug" = "mailpit-${PROJECT_SLUG}" ] || [ "$slug" = "xhgui-${PROJECT_SLUG}" ] || [ "$slug" = "adminer-${PROJECT_SLUG}" ]; then
     # Known Coder app slugs (defined as coder_app resources in the Terraform template):
     # use Host() rule so the Coder subdomain proxy URL routes correctly.
@@ -149,6 +178,11 @@ while IFS= read -r router; do
          .http.routers.\"${ROUTER_NAME}\".middlewares = [env(MW)] |
          .http.routers.\"${ROUTER_NAME}\".tls = false" \
       /tmp/coder-routes-raw.yaml
+    if [ "$svc_name" = "web" ]; then
+      MAILPIT_URL="https://${CODER_HOST}"
+    else
+      DESCRIBE_URLS["$svc_name"]="https://${CODER_HOST}"
+    fi
     echo "  + ${slug}: ${entrypoints[*]} → ${service}  (https://${CODER_HOST})"
   else
     # Dynamic add-on services (no dedicated coder_app): PathPrefix("/") catches any
@@ -172,7 +206,16 @@ while IFS= read -r router; do
          .http.routers.\"${ROUTER_NAME}\".tls = false |
          .http.routers.\"${ROUTER_NAME}\".priority = 10" \
       /tmp/coder-routes-raw.yaml
-    echo "  + ${slug}: ${entrypoints[*]} → ${service}  (https://${ext_port}--${AGENT}--${WORKSPACE}--${OWNER}.${DOMAIN})"
+    DYNAMIC_URL="https://${ext_port}--${AGENT}--${WORKSPACE}--${OWNER}.${DOMAIN}"
+    # svc_name="web" here means a web_extra_exposed_ports entry (playwright,
+    # kasmvnc, ...) — not a real service, so it's excluded (see comment above
+    # DESCRIBE_URLS). Anything else is a genuine custom/add-on service that
+    # simply doesn't have a dedicated coder_app slug yet; still worth reflecting
+    # in 'ddev describe' via its dynamic port-forwarding URL.
+    if [ "$svc_name" != "web" ]; then
+      DESCRIBE_URLS["$svc_name"]="$DYNAMIC_URL"
+    fi
+    echo "  + ${slug}: ${entrypoints[*]} → ${service}  (${DYNAMIC_URL})"
   fi
 
 done < <(yq e '.http.routers | keys | .[]' "$MERGED" 2>/dev/null)
@@ -190,3 +233,35 @@ if docker ps --format '{{.Names}}' 2>/dev/null | grep -q "^ddev-router$"; then
 else
   echo "Note: ddev-router not running; config will be loaded on next ddev start"
 fi
+
+# Regenerate .ddev/docker-compose.coder-describe.yaml so 'ddev describe'/'ddev launch'
+# reflect exactly what was just routed above — see the DESCRIBE_URLS comment earlier
+# in this script for why this only covers real compose services, not
+# web_extra_exposed_ports rows. DDEV_APPROOT is provided by DDEV for host commands
+# (their cwd is wherever `ddev` was invoked from, not the project root).
+if [ -n "${DDEV_APPROOT:-}" ] && [ -n "$WEB_URL" ]; then
+  DESCRIBE_FILE="${DDEV_APPROOT}/.ddev/docker-compose.coder-describe.yaml"
+  {
+    echo "#ddev-silent-no-warn"
+    echo "# Auto-generated by ddev coder-routes — do not edit."
+    echo "services:"
+    echo "  web:"
+    echo "    x-ddev:"
+    echo "      describe-url-port: |"
+    echo "        ${WEB_URL}"
+    if [ -n "$MAILPIT_URL" ]; then
+      echo "        Mailpit: ${MAILPIT_URL}"
+    fi
+    echo "      describe-info: \"Use: ddev launch\""
+
+    for svc_name in "${!DESCRIBE_URLS[@]}"; do
+      echo "  ${svc_name}:"
+      echo "    x-ddev:"
+      echo "      describe-url-port: |"
+      echo "        ${DESCRIBE_URLS[$svc_name]}"
+    done
+  } > "$DESCRIBE_FILE"
+  echo "✓ Wrote $(basename "$DESCRIBE_FILE") (covers: web ${!DESCRIBE_URLS[*]})"
+else
+  echo "Note: skipping docker-compose.coder-describe.yaml (DDEV_APPROOT unset or no primary web route found)"
+fi

image/scripts/.ddev/commands/host/coder-setup

@@ -46,8 +46,34 @@ hooks:
 EOF
 echo "✓ Wrote .ddev/config.coder.yaml"
 
-# Write docker-compose.coder-describe.yaml so 'ddev describe' shows the Coder web URL.
-# Must exist before 'ddev start' — DDEV reads docker-compose files at start time.
+# Write an initial docker-compose.coder-describe.yaml covering just the primary
+# web service + Mailpit, so 'ddev describe' shows a working Coder URL even before
+# the project has ever been started. Everything else — xhgui, adminer, or any other
+# add-on/custom service that gets its own router — is handled dynamically by
+# `coder-routes` (which runs on every post-start) rather than hardcoded here: it
+# already discovers every real service from the merged Traefik config, computes
+# each one's Coder URL for routing, and rewrites this same file with an entry per
+# service it finds.
+#
+# Note the one-restart lag: DDEV only reads x-ddev.describe-url-port from the
+# compose config it built during the *last* `ddev start`/`ddev restart`, not fresh
+# on every `ddev describe` call. So a service coder-routes discovers during THIS
+# start's post-start hook won't show its Coder URL in `ddev describe` until the
+# NEXT start/restart — confirmed empirically: after one `ddev restart`, a newly
+# discovered service's row was still missing its Coder URL; a second restart
+# picked it up. This bootstrap block covers the primary web+Mailpit URLs (the only
+# ones computable without a running project) so that pair is right from the very
+# first start; every other service converges one restart after coder-routes first
+# sees it, same as this block already required before this change.
+#
+# Note this mechanism only applies to real docker-compose services. It cannot fix
+# the separate "web_extra_exposed_ports" rows some add-ons contribute to
+# 'ddev describe' (e.g. ddev-playwright's "playwright" row, a VNC add-on's
+# "kasmvnc" row): cmd/ddev/cmd/describe.go's WebExtraExposedPorts stanza always
+# builds that row's URL itself (https://<project-hostname>:<https_port>) and never
+# consults describe-url-port. Those rows will keep showing the raw *.ddev.site URL
+# — unreachable through Coder's proxy — until ddev/ddev adds support for overriding
+# them; that's a separate upstream feature request against https://github.com/ddev/ddev.
 _WORKSPACE="${CODER_WORKSPACE_NAME:-}"
 _OWNER="${CODER_WORKSPACE_OWNER_NAME:-}"
 _DOMAIN=""
@@ -63,6 +89,7 @@ if [ -n "$_WORKSPACE" ] && [ -n "$_OWNER" ] && [ -n "$_DOMAIN" ] && [ -n "${DDEV
   cat > .ddev/docker-compose.coder-describe.yaml << EOF
 #ddev-silent-no-warn
 # Auto-generated by ddev coder-setup — do not edit.
+# Superseded by coder-routes after the first 'ddev start' (see comment above).
 services:
   web:
     x-ddev: