allow specification of app root

this can not only be handled on ingress level, but we need to mount the
express app also on the app root level. This basically just works out of the
box.

.env.defaults

 CACHE_TTL=30000
 PORT=8080
 LOG_LEVEL=info
+APP_ROOT=/

helm/core-manifest-service/templates/deployment.yaml

@@ -25,6 +25,8 @@ spec:
               value: "{{ .Values.cacheTTL | int }}"
             - name: LOG_LEVEL
               value: "{{ .Values.logLevel }}"
+            - name: APP_ROOT
+              value: "{{ .Values.appRoot }}"
           ports:
             - name: http
               containerPort: {{ .Values.containerPort | default 8080 }}

helm/core-manifest-service/values.yaml

@@ -98,3 +98,5 @@ probe:
 
 cacheTTL: 30000
 logLevel: info
+manifests: []
+appRoot: '/'

src/index.js

@@ -3,12 +3,16 @@
 import { config } from 'dotenv-defaults'
 import { getLogger } from './logger.js'
 import { createApp } from './createApp.js'
+import express from 'express'
 
 config()
 
+const root = express()
 const app = createApp()
 
 // Binds and listens for connections on the specified host and port
-app.listen(process.env.PORT, () => {
+root.listen(process.env.PORT, () => {
   getLogger().info(`manifest-service listening on port ${process.env.PORT}`)
 })
+
+root.use(process.env.APP_ROOT, app)