refactor: [#301] implement PortDerivation for GrafanaConfig

Author: josecelano

docs/issues/301-phase-4-service-topology-ddd-alignment.md

@@ -314,10 +314,10 @@ impl TrackerServiceContext {
 
 ### Step 3: Implement PortDerivation for Grafana
 
-- [ ] 3.1 Implement `PortDerivation` for `GrafanaConfig` in domain
-- [ ] 3.2 Add unit tests for Grafana port derivation
-- [ ] 3.3 Update infrastructure `GrafanaServiceConfig` to use domain trait
-- [ ] 3.4 Remove `derive_grafana_ports()` calls from infrastructure
+- [x] 3.1 Implement `PortDerivation` for `GrafanaConfig` in domain
+- [x] 3.2 Add unit tests for Grafana port derivation
+- [x] 3.3 Update infrastructure `GrafanaServiceConfig` to use domain trait
+- [x] 3.4 Remove `derive_grafana_ports()` calls from infrastructure
 
 ### Step 4: Implement PortDerivation for Tracker (Most Complex)
 

src/domain/grafana/config.rs

@@ -2,6 +2,7 @@
 
 use serde::{Deserialize, Serialize};
 
+use crate::domain::topology::{PortBinding, PortDerivation};
 use crate::shared::domain_name::DomainName;
 use crate::shared::secrets::Password;
 
@@ -116,6 +117,23 @@ impl Default for GrafanaConfig {
     }
 }
 
+impl PortDerivation for GrafanaConfig {
+    /// Derives port bindings for Grafana
+    ///
+    /// Implements PORT-07 and PORT-08:
+    /// - Without TLS: expose port 3000 directly
+    /// - With TLS: don't expose (Caddy handles it)
+    fn derive_ports(&self) -> Vec<PortBinding> {
+        // PORT-07: Grafana 3000 exposed only without TLS
+        // PORT-08: Grafana 3000 NOT exposed with TLS
+        if self.use_tls_proxy {
+            vec![]
+        } else {
+            vec![PortBinding::tcp(3000, "Grafana dashboard")]
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -233,4 +251,53 @@ mod tests {
             config.admin_password.expose_secret()
         );
     }
+
+    // =========================================================================
+    // Port derivation tests (PORT-07, PORT-08)
+    // =========================================================================
+
+    mod port_derivation {
+        use super::*;
+        use crate::domain::tracker::Protocol;
+
+        #[test]
+        fn it_should_expose_port_3000_when_tls_disabled() {
+            // PORT-07: Grafana 3000 exposed only without TLS
+            let config =
+                GrafanaConfig::new("admin".to_string(), "password".to_string(), None, false);
+
+            let ports = config.derive_ports();
+
+            assert_eq!(ports.len(), 1);
+            let port = &ports[0];
+            assert_eq!(port.host_port(), 3000);
+            assert_eq!(port.container_port(), 3000);
+            assert_eq!(port.protocol(), Protocol::Tcp);
+        }
+
+        #[test]
+        fn it_should_not_expose_port_when_tls_enabled() {
+            // PORT-08: Grafana 3000 NOT exposed with TLS
+            let domain = DomainName::new("grafana.example.com").unwrap();
+            let config = GrafanaConfig::new(
+                "admin".to_string(),
+                "password".to_string(),
+                Some(domain),
+                true,
+            );
+
+            let ports = config.derive_ports();
+
+            assert!(ports.is_empty());
+        }
+
+        #[test]
+        fn it_should_include_description_for_grafana_port() {
+            let config = GrafanaConfig::default();
+
+            let ports = config.derive_ports();
+
+            assert_eq!(ports[0].description(), "Grafana dashboard");
+        }
+    }
 }

src/infrastructure/templating/docker_compose/template/wrappers/docker_compose/context/builder.rs

@@ -146,15 +146,10 @@ impl DockerComposeContextBuilder {
             .map(|config| PrometheusServiceConfig::new(config, has_grafana));
 
         // Build Grafana service config if enabled
-        let grafana = self.grafana_config.map(|config| {
-            let has_tls = config.use_tls_proxy();
-            GrafanaServiceConfig::new(
-                config.admin_user().to_string(),
-                config.admin_password().clone(),
-                has_tls,
-                has_caddy,
-            )
-        });
+        let grafana = self
+            .grafana_config
+            .as_ref()
+            .map(|config| GrafanaServiceConfig::new(config, has_caddy));
 
         // Build Caddy service config if enabled
         let caddy = if has_caddy {

src/infrastructure/templating/docker_compose/template/wrappers/docker_compose/context/grafana.rs

@@ -3,11 +3,11 @@
 // External crates
 use serde::Serialize;
 
-use crate::domain::topology::Network;
+use crate::domain::grafana::GrafanaConfig;
+use crate::domain::topology::{Network, PortDerivation};
 use crate::shared::secrets::Password;
 
 use super::port_definition::PortDefinition;
-use super::port_derivation::derive_grafana_ports;
 
 /// Grafana service configuration for Docker Compose
 ///
@@ -41,25 +41,19 @@ impl GrafanaServiceConfig {
     ///
     /// # Arguments
     ///
-    /// * `admin_user` - Grafana admin username
-    /// * `admin_password` - Grafana admin password
-    /// * `has_tls` - Whether Grafana has TLS enabled (via Caddy)
+    /// * `config` - The domain Grafana configuration
     /// * `has_caddy` - Whether Caddy TLS proxy is enabled (adds `proxy_network`)
     #[must_use]
-    pub fn new(
-        admin_user: String,
-        admin_password: Password,
-        has_tls: bool,
-        has_caddy: bool,
-    ) -> Self {
+    pub fn new(config: &GrafanaConfig, has_caddy: bool) -> Self {
         let networks = Self::compute_networks(has_caddy);
-        let port_bindings = derive_grafana_ports(has_tls);
+        // Use domain PortDerivation trait for port logic
+        let port_bindings = config.derive_ports();
         let ports = port_bindings.iter().map(PortDefinition::from).collect();
 
         Self {
-            admin_user,
-            admin_password,
-            has_tls,
+            admin_user: config.admin_user().to_string(),
+            admin_password: config.admin_password().clone(),
+            has_tls: config.use_tls_proxy(),
             ports,
             networks,
         }
@@ -80,28 +74,39 @@ impl GrafanaServiceConfig {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::shared::DomainName;
+
+    fn make_config(use_tls_proxy: bool) -> GrafanaConfig {
+        if use_tls_proxy {
+            GrafanaConfig::new(
+                "admin".to_string(),
+                "password".to_string(),
+                Some(DomainName::new("grafana.example.com").unwrap()),
+                true,
+            )
+        } else {
+            GrafanaConfig::new("admin".to_string(), "password".to_string(), None, false)
+        }
+    }
 
     #[test]
     fn it_should_connect_grafana_to_visualization_network() {
-        let config =
-            GrafanaServiceConfig::new("admin".to_string(), Password::new("password"), false, false);
+        let config = GrafanaServiceConfig::new(&make_config(false), false);
 
         assert!(config.networks.contains(&Network::Visualization));
     }
 
     #[test]
     fn it_should_not_connect_grafana_to_proxy_network_when_caddy_disabled() {
-        let config =
-            GrafanaServiceConfig::new("admin".to_string(), Password::new("password"), false, false);
+        let config = GrafanaServiceConfig::new(&make_config(false), false);
 
         assert_eq!(config.networks, vec![Network::Visualization]);
         assert!(!config.networks.contains(&Network::Proxy));
     }
 
     #[test]
     fn it_should_connect_grafana_to_proxy_network_when_caddy_enabled() {
-        let config =
-            GrafanaServiceConfig::new("admin".to_string(), Password::new("password"), true, true);
+        let config = GrafanaServiceConfig::new(&make_config(true), true);
 
         assert_eq!(
             config.networks,
@@ -111,8 +116,7 @@ mod tests {
 
     #[test]
     fn it_should_serialize_networks_to_name_strings() {
-        let config =
-            GrafanaServiceConfig::new("admin".to_string(), Password::new("password"), true, true);
+        let config = GrafanaServiceConfig::new(&make_config(true), true);
 
         let json = serde_json::to_value(&config).expect("serialization should succeed");
 
@@ -123,17 +127,15 @@ mod tests {
 
     #[test]
     fn it_should_expose_port_3000_when_tls_disabled() {
-        let config =
-            GrafanaServiceConfig::new("admin".to_string(), Password::new("password"), false, false);
+        let config = GrafanaServiceConfig::new(&make_config(false), false);
 
         assert_eq!(config.ports.len(), 1);
         assert_eq!(config.ports[0].binding(), "3000:3000");
     }
 
     #[test]
     fn it_should_not_expose_ports_when_tls_enabled() {
-        let config =
-            GrafanaServiceConfig::new("admin".to_string(), Password::new("password"), true, true);
+        let config = GrafanaServiceConfig::new(&make_config(true), true);
 
         assert!(config.ports.is_empty());
     }