Incompatible use of dynamic environment variables when configuring fos_http_cache.proxy_client.http...base_url

With this config

fos_http_cache.yaml
    fos_http_cache:
        proxy_client:
            default: varnish
            varnish:
                http:
                    base_url: test.local.net:443

replacing the explicit url with ENV var

.env
    BASE_URL='test.local.net'

services.yaml
    parameters:
        base.url:   '%env(BASE_URL)%'

fos_http_cache.yaml
    fos_http_cache:
        proxy_client:
            default: varnish
            varnish:
                http:
-                   base_url: test.local.net:443
+                   base_url: '%base.url%:443'

also 'works' (no errors, haven't yet fully tested varnish purge etc)

but if you try to inject the PORT dynamically,

.env
    BASE_URL='test.local.net'
+   BASE_PORT='443'
(or BASE_PORT=443)

services.yaml
    parameters:
        base.url:   '%env(BASE_URL)%'
+       base.port:  '%env(BASE_PORT)%'

fos_http_cache.yaml
    fos_http_cache:
        proxy_client:
            default: varnish
            varnish:
                http:
-                   base_url: test.local.net:443
-                   base_url: '%base.url%:443'
+                   base_url: '%base.url%:%base.port%'

profiler shows

(2/2) EnvParameterException

    Incompatible use of dynamic environment variables "BASE_URL", "BASE_PORT" found in parameters.
    in Compiler.php (line 112)
    at Compiler->compile(object(ContainerBuilder))in ContainerBuilder.php (line 713)
    at ContainerBuilder->compile()in Kernel.php (line 513)
    at Kernel->initializeContainer()in Kernel.php (line 125)
    at Kernel->boot()in Kernel.php (line 185)
    at Kernel->handle(object(Request))in index.php (line 37)

(1/2) InvalidConfigurationException

    Not a valid base path: "http://%env(BASE_URL)%:%env(BASE_PORT)%"
    in FOSHttpCacheExtension.php (line 566)
    at FOSHttpCacheExtension->validateUrl('http://env_BASE_URL_82a306f54867199848964602d02a1770:env_BASE_PORT_806e9358ff4bd1bbdd72ce13ad0ce3ca', 'Not a valid base path: "%s"')in FOSHttpCacheExtension.php (line 379)
    at FOSHttpCacheExtension->createHttpDispatcherDefinition(object(MergeExtensionConfigurationContainerBuilder), array('servers' => array('127.0.0.1:6081'), 'base_url' => 'env_BASE_URL_82a306f54867199848964602d02a1770:env_BASE_PORT_806e9358ff4bd1bbdd72ce13ad0ce3ca', 'http_client' => null), 'fos_http_cache.proxy_client.varnish.http_dispatcher')in FOSHttpCacheExtension.php (line 399)
    at FOSHttpCacheExtension->loadVarnish(object(MergeExtensionConfigurationContainerBuilder), object(XmlFileLoader), array('tags_header' => 'X-Cache-Tags', 'header_length' => 7500, 'http' => array('servers' => array('127.0.0.1:6081'), 'base_url' => 'env_BASE_URL_82a306f54867199848964602d02a1770:env_BASE_PORT_806e9358ff4bd1bbdd72ce13ad0ce3ca', 'http_client' => null)))in FOSHttpCacheExtension.php (line 347)
    at FOSHttpCacheExtension->loadProxyClient(object(MergeExtensionConfigurationContainerBuilder), object(XmlFileLoader), array('default' => 'varnish', 'varnish' => array('tags_header' => 'X-Cache-Tags', 'header_length' => 7500, 'http' => array('servers' => array('127.0.0.1:6081'), 'base_url' => 'env_BASE_URL_82a306f54867199848964602d02a1770:env_BASE_PORT_806e9358ff4bd1bbdd72ce13ad0ce3ca', 'http_client' => null))))in FOSHttpCacheExtension.php (line 68)
    at FOSHttpCacheExtension->load(array(array('proxy_client' => array('default' => 'varnish', 'varnish' => array('tags_header' => 'X-Cache-Tags', 'header_length' => 7500, 'default_ban_headers' => null, 'http' => array('servers' => array('127.0.0.1:6081'), 'base_url' => 'env_BASE_URL_82a306f54867199848964602d02a1770:env_BASE_PORT_806e9358ff4bd1bbdd72ce13ad0ce3ca'))))), object(MergeExtensionConfigurationContainerBuilder))in MergeExtensionConfigurationPass.php (line 71)
    at MergeExtensionConfigurationPass->process(object(ContainerBuilder))in MergeExtensionConfigurationPass.php (line 39)
    at MergeExtensionConfigurationPass->process(object(ContainerBuilder))in Compiler.php (line 95)
    at Compiler->compile(object(ContainerBuilder))in ContainerBuilder.php (line 713)
    at ContainerBuilder->compile()in Kernel.php (line 513)
    at Kernel->initializeContainer()in Kernel.php (line 125)
    at Kernel->boot()in Kernel.php (line 185)
    at Kernel->handle(object(Request))in index.php (line 37)

and at console

bcs cache:clear
string(99) "http://env_BASE_URL_91cc1a4dda9c935f7aa32b51209832e8:env_BASE_PORT_fae3ce89901ece848ab04cb8210721dd"

In Compiler.php line 112:

  Incompatible use of dynamic environment variables "BASE_URL", "BASE_PORT" found in parameters.

In FOSHttpCacheExtension.php line 566:

  Not a valid base path: "http://%env(BASE_URL)%:%env(BASE_PORT)%"

fwi, references to similar/relevant(?) issue, re: injection of dynamic env vars in other bundle, snd-redis

https://github.com/symfony/symfony/issues/20850 https://github.com/symfony/symfony/commit/2422f7da9b004ef1a13c1429e711c7d4c03c239d

And, just adding @dbu 's comment from Slack in case it disappears over there:

I'll have to check at which point variables are supposed to be resolved then. i thought it would be before we look at them ...

FriendsOfSymfony / FOSHttpCacheBundle

Incompatible use of dynamic environment variables when configuring fos_http_cache.proxy_client.http...base_url #449