Migrate off functions.config() + bump functions to Node 24

Closes #1669.

functions.config() / Cloud Runtime Config is deprecated (shuts down
March 2027). The function code already reads everything from process.env
via functions/.env* files, so this finishes the migration in the
remaining places that still referenced the legacy config:

- e2e CI: stop writing the legacy .runtimeconfig.json; convert the
  nested config secret into functions/.env.local (the dotenv the
  emulator loads) with jq.
- docs/install: replace `firebase functions:config:set` /
  `functions:config:get > .runtimeconfig.json` with .env instructions.
- userInvite trigger: drop the stale functions:config:get comment.

Also bump the functions runtime to Node 24 (engines.node + .nvmrc).

Note: nodejs24 is GA on Cloud Functions, but firebase-tools <= 15.20.0
(current latest) still caps deploy validation at nodejs22. Until a
firebase-tools release adds nodejs24, deploy the functions with
`gcloud functions deploy --runtime nodejs24` (or bump firebase-tools
once it supports it); plain `firebase deploy` will reject the runtime.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: HugoGresse

.github/workflows/test-e2e.yml

@@ -27,14 +27,25 @@ jobs:
       with:
           credentials_json: '${{ secrets.E2E_GCLOUD_CREDENTIAL_OPEN_FEEDBACK_CYPRESS }}'
 
-    - name: "Create .runtimeconfig.json"
-      run: 'echo "$RUNTIME_CONFIG_TEST" > functions/.runtimeconfig.json'
+    # Functions now read config from process.env (functions/.env*), not the
+    # deprecated functions.config()/.runtimeconfig.json. Convert the legacy
+    # nested config secret into the dotenv the emulator loads (.env.local).
+    - name: "Create functions/.env.local"
+      run: |
+            echo "$RUNTIME_CONFIG_TEST" | jq -r '
+              "APP_ENV=\(.app.env // "test")",
+              "APP_URL=\(.app.url // "")",
+              "APP_CONTACTEMAIL=\(.app.contactemail // "")",
+              "APP_RECAPTCHAV3SECRET=\(.app.recaptchav3secret // "")",
+              "MAILGUN_DOMAIN=\(.mailgun.domain // "")",
+              "MAILGUN_KEY=\(.mailgun.key // "")",
+              "MAILGUN_API=\(.mailgun.api // "")",
+              "OPSGENIE_KEY=\(.opsgenie.key // "")",
+              "OPSGENIE_API=\(.opsgenie.api // "")"
+            ' > functions/.env.local
       shell: bash
       env:
           RUNTIME_CONFIG_TEST: ${{secrets.RUNTIME_CONFIG_TEST}}
-    - name: "test"
-      run: 'cat functions/.runtimeconfig.json'
-      shell: bash
 
     - name: Install functions dependencies
       run: |

.nvmrc

@@ -1 +1 @@
-20
+24

docs/app/1-install.mdx

@@ -35,41 +35,48 @@ The application sends emails through the Mailgun API
 
 You have to create a Mailgun account if you want to send those emails, if not the app will still works perfectly but without sending any email.
 
-Mailgun API is used to send email through Cloud Functions, so you will have to add environment variables with Firebase CLI:
+Mailgun API is used to send email through Cloud Functions. Configuration uses
+environment variables (the [Firebase params/env approach](https://firebase.google.com/docs/functions/config-env);
+the legacy `functions.config()` / Runtime Config is deprecated). Add the
+variables to a dotenv file under `functions/`:
 
-- The application URL: app.url (ex: `http://localhost:3000`)
-- The API key: mailgun.key
-- The domain name: mailgun.domain
-- The Mailgun API url: mailgun.api (ex https://api.eu.mailgun.net/v3/SOMETHINGLIKE_THIS/messages)
+- The application URL: `APP_URL` (ex: `http://localhost:3000`)
+- The API key: `MAILGUN_KEY`
+- The domain name: `MAILGUN_DOMAIN`
+- The Mailgun API url: `MAILGUN_API` (ex https://api.eu.mailgun.net/v3/SOMETHINGLIKE_THIS/messages)
 
-Here the command to register those variables:
+Firebase loads `functions/.env` (all projects), `functions/.env.<project-id>`
+(per project, used on deploy), and `functions/.env.local` (used by the
+emulator only). Example `functions/.env.local`:
 
-    firebase functions:config:set app.url="https://myserver.com" mailgun.key="MAILGUN API KEY" mailgun.domain="MAILGUN DOMAIN"  mailgun.api="https://api.eu.mailgun.net/v3/SOMETHINGLIKE_THIS/messages"
+    APP_ENV=development
+    APP_URL=https://myserver.com
+    MAILGUN_KEY=MAILGUN_API_KEY
+    MAILGUN_DOMAIN=MAILGUN_DOMAIN
+    MAILGUN_API=https://api.eu.mailgun.net/v3/SOMETHINGLIKE_THIS/messages
 
-To test cloud functions with Mailgun on your local machine (with cloud function shell), you will need to generate ``.runtimeconfig.json` file with environment variables :
-
-    firebase functions:config:get > .runtimeconfig.json
+> Keep secrets out of version control: store them in a gitignored `.env*.local`
+> (or use [Cloud Secret Manager](https://firebase.google.com/docs/functions/config-env#secret-manager)).
 
 > Important Note: Mailgun is an external service from Firebase and Google, so to be able use it with you will need to activate Firebase pricing.
 
 ### Configure OpsGenie (optional)
 The application report alerting using OpsGenie, it is optional and the app will still works perfectly but without any alerting.
 
-You will have to add environment variables with Firebase CLI:
-
-- The application URL: app.url (ex: `http://localhost:3000`)
-- The OpsGenie API key: opsgenie.key
-- The OpsGenie api domain: opsgenie.api
-- For contact email (optional): app.contactemail
-- For contact email captcha, the recaptcha V3 Secret: app. recaptchav3secret
-
-Here the command to register those variables:
+Add the following environment variables to a `functions/` dotenv file (see the
+Mailgun section above for how Firebase loads them):
 
-    firebase functions:config:set app.url="https://myserver.com" opsgenie.api="https://api.eu.opsgenie.com" opsgenie.key="xxxxx-xxxxxx-xxxxxx-xxxxx"
+- The application URL: `APP_URL` (ex: `http://localhost:3000`)
+- The OpsGenie API key: `OPSGENIE_KEY`
+- The OpsGenie api domain: `OPSGENIE_API`
+- For contact email (optional): `APP_CONTACTEMAIL`
+- For contact email captcha, the recaptcha V3 Secret: `APP_RECAPTCHAV3SECRET`
 
-To test alerting on your local machine (with cloud function shell), you will need to generate ``.runtimeconfig.json` file with environment variables :
+Example additions to `functions/.env.local`:
 
-    firebase functions:config:get > .runtimeconfig.json
+    APP_URL=https://myserver.com
+    OPSGENIE_API=https://api.eu.opsgenie.com
+    OPSGENIE_KEY=xxxxx-xxxxxx-xxxxxx-xxxxx
 
 > Important Note: OpsGenie is an external service from Firebase and Google, so to be able use it with you will need to activate Firebase pricing.
 
@@ -98,10 +105,11 @@ Cloud functions uses its own `package.json`, first install dependencies. From th
 npm i
 ```
 
-And then from the root of the project:
+And then add the admin contact email to `functions/.env.<your-project-id>`
+(created automatically on first deploy if missing):
 
 ```
-firebase functions:config:set 'app.contactemail=<ADMIN_EMAIL>'
+APP_CONTACTEMAIL=<ADMIN_EMAIL>
 ```
 
 The next deploy will also deploy Firebase Cloud Functions

functions/package.json

@@ -13,7 +13,7 @@
         "test": "vitest"
     },
     "engines": {
-        "node": "20"
+        "node": "24"
     },
     "main": "lib/index.js",
     "dependencies": {

functions/src/triggers/invites/userInvite.ts

@@ -10,8 +10,8 @@ import { onDocumentCreated } from 'firebase-functions/v2/firestore'
 
 // userInviteCreated is called when an user as been invited to a project or an organization.
 // An email is sent to him with the invitation link.
-// To test
-// > firebase functions:config:get > .runtimeconfig.json
+// To test (config comes from functions/.env* via process.env, not the
+// deprecated functions.config()):
 // > firebase functions:shell
 // - for event/project
 // > userInviteCreated({projectId: "", projectName: "", originUserName: "", destinationUserInfo: ""})