feature: https.acme_staging takes Caddy's certificates from Let's Encrypt's staging environment.

debian-package/src/usr/lib/vpn-router/vpnrouter.py

@@ -66,7 +66,8 @@ SCHEMA = {
                    'status_content': 'basic', 'shell': False, 'shell_idle_minutes': 15, 'shell_auth_timeout': 15,
                    'log_files': []},
     'ssh':        {'ldap_login': False},
-    'https':      {'enabled': True, 'email': '', 'web_port': 7444, 'manager_port': 7443, 'caddy_source': 'ubuntu'},
+    'https':      {'enabled': True, 'email': '', 'web_port': 7444, 'manager_port': 7443, 'caddy_source': 'ubuntu',
+                   'acme_staging': False},
     'oidc':       {'enabled': False},
     'sites':      {'enabled': False, 'upload_max_mb': 512, 'webdav': False, 'webdav_port': 7445},
     'dns':        {'enabled': False, 'nameserver': '', 'addresses': [], 'listen': 'external', 'ttl': 300},
@@ -164,6 +165,9 @@ MANAGER_PORT   = 7080
 #: Where vpn-router-setup installs Caddy from, https.caddy_source: the Ubuntu archive or Caddy's own repository.
 CADDY_SOURCES = ('ubuntu', 'upstream')
 
+#: The ACME directory of Let's Encrypt's staging environment, Caddy's only CA while https.acme_staging is true.
+ACME_STAGING_CA = 'https://acme-staging-v02.api.letsencrypt.org/directory'
+
 #: Caddy's own repository, which https.caddy_source upstream configures: the source, its signing key and their URLs.
 CADDY_APT_SOURCE = pathlib.Path('/etc/apt/sources.list.d/caddy-stable.sources')
 CADDY_KEYRING    = pathlib.Path('/etc/apt/keyrings/caddy-stable.asc')
@@ -1034,6 +1038,7 @@ def build_context(cfg, public_ip=None):
         'web_port':        _get(cfg, 'web', 'port'),
         'https_enabled':   _get(cfg, 'https', 'enabled'),
         'https_email':     _get(cfg, 'https', 'email'),
+        'https_acme_ca':   ACME_STAGING_CA if _get(cfg, 'https', 'acme_staging') else '',
         'https_web_port':  _get(cfg, 'https', 'web_port'),
         'https_manager_port': _get(cfg, 'https', 'manager_port'),
         'pki_publish':     _get_list(cfg, 'pki', 'publish'),

debian-package/src/usr/share/vpn-router/templates/Caddyfile.j2

@@ -4,6 +4,9 @@
 {%- if https_email %}
 	email {{ https_email }}
 {%- endif %}
+{%- if https_acme_ca %}
+	acme_ca {{ https_acme_ca }}
+{%- endif %}
 {%- if pki_cas %}
 	skip_install_trust
 	pki {