badge-service: verify App Store and Google Play purchases (#7654)

scripts/badge-service/badge_service.ini.example

@@ -36,6 +36,22 @@ session_minutes = 60
 waiting_seconds = 3
 idle_seconds = 60
 
+; optional; without it every App Store receipt is answered provider_not_configured, which the app retries later.
+; root_certificate is https://www.apple.com/certificateauthority/AppleRootCA-G3.cer, in DER;
+; uncomment its mount in compose.yml.
+;[apple]
+;bundle_id = chat.simplex.app
+;root_certificate = /etc/simplex-badge-service/AppleRootCA-G3.cer
+
+; optional; without it every Play receipt is answered provider_not_configured, which the app retries later.
+; service_account_file is the JSON key of a service account with the Play Console permissions "View
+; financial data, orders, and cancellation survey responses" and "Manage orders and subscriptions", to
+; read and acknowledge purchases. Without the second, a purchase the app has not already acknowledged
+; itself is answered internal until the permission is granted. Uncomment its mount in compose.yml; the file must be readable by the service's user alone.
+;[google]
+;package_name = chat.simplex.app
+;service_account_file = /etc/simplex-badge-service/play-service-account.json
+
 ; index is the one clients verify against; private_key is from `simplex-chat badge keygen`.
 ; To rotate, change both together, once clients trust the new index.
 [issuer]
@@ -54,6 +70,7 @@ private_key = replace-me
 ;description = Welcome to the badges group
 
 ; local testing only, in both run modes: accepts any well-formed App Store or Play receipt without
-; verifying it, so anyone who can reach this service can mint badges
+; verifying it, so anyone who can reach this service can mint badges. The service refuses to start
+; with this on beside an [apple] or [google] section.
 [dev]
 accept_unverified_store_receipts = off

scripts/badge-service/compose.yml

@@ -20,5 +20,7 @@ services:
       - "/etc/simplex-badge-service/badge_service.ini"
     volumes:
       - ./badge_service.ini:/etc/simplex-badge-service/badge_service.ini:ro
+      # - ./AppleRootCA-G3.cer:/etc/simplex-badge-service/AppleRootCA-G3.cer:ro
+      # - ./play-service-account.json:/etc/simplex-badge-service/play-service-account.json:ro
       - ./web:/srv/webapp
     stop_grace_period: 10s