1 files changed, 84 insertions, 0 deletions
diff --git a/crates/common/tedge_config/src/tedge_config_defaults.rs b/crates/common/tedge_config/src/tedge_config_defaults.rs
new file mode 100644
index 00000000..7f6b98ab
--- /dev/null
+++ b/crates/common/tedge_config/src/tedge_config_defaults.rs
@@ -0,0 +1,84 @@
+use crate::models::FilePath;
+use crate::TEdgeConfigLocation;
+use crate::{Flag, Port};
+use std::path::Path;
+
+const DEFAULT_ETC_PATH: &str = "/etc";
+const DEFAULT_PORT: u16 = 1883;
+
+/// Stores default values for use by `TEdgeConfig` in case no configuration setting
+/// is available.
+///
+/// We DO NOT base the defaults on the currently executing user. Instead, we derive
+/// the defaults from the location of the `tedge.toml` file. This allows run
+/// `sudo tedge -c '$HOME/.tedge/tedge.toml ...` where the defaults are picked up
+/// correctly.
+///
+/// The choice, where to find `tedge.toml` on the other hand is based on the executing user AND the
+/// env `$HOME`.  But once we have found `tedge.toml`, we never again have to care about the
+/// executing user (except when `chown`ing files...).
+///
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct TEdgeConfigDefaults {
+    /// Default device cert path
+    pub default_device_cert_path: FilePath,
+
+    /// Default device key path
+    pub default_device_key_path: FilePath,
+
+    /// Default path for azure root certificates
+    pub default_azure_root_cert_path: FilePath,
+
+    /// Default path for c8y root certificates
+    pub default_c8y_root_cert_path: FilePath,
+
+    /// Default mapper timestamp bool
+    pub default_mapper_timestamp: Flag,
+
+    /// Default port for mqtt internal listener
+    pub default_mqtt_port: Port,
+}
+
+impl From<&TEdgeConfigLocation> for TEdgeConfigDefaults {
+    fn from(config_location: &TEdgeConfigLocation) -> Self {
+        let system_cert_path = Path::new(DEFAULT_ETC_PATH).join("ssl").join("certs");
+        Self {
+            default_device_cert_path: config_location
+                .tedge_config_root_path()
+                .join("device-certs")
+                .join("tedge-certificate.pem")
+                .into(),
+            default_device_key_path: config_location
+                .tedge_config_root_path()
+                .join("device-certs")
+                .join("tedge-private-key.pem")
+                .into(),
+            default_azure_root_cert_path: system_cert_path.clone().into(),
+            default_c8y_root_cert_path: system_cert_path.into(),
+            default_mapper_timestamp: Flag(true),
+            default_mqtt_port: Port(DEFAULT_PORT),
+        }
+    }
+}
+
+#[test]
+fn test_from_tedge_config_location() {
+    let config_location = TEdgeConfigLocation::from_custom_root("/opt/etc/_tedge");
+    let defaults = TEdgeConfigDefaults::from(&config_location);
+
+    assert_eq!(
+        defaults,
+        TEdgeConfigDefaults {
+            default_device_cert_path: FilePath::from(
+                "/opt/etc/_tedge/device-certs/tedge-certificate.pem"
+            ),
+            default_device_key_path: FilePath::from(
+                "/opt/etc/_tedge/device-certs/tedge-private-key.pem"
+            ),
+            default_azure_root_cert_path: FilePath::from("/etc/ssl/certs"),
+            default_c8y_root_cert_path: FilePath::from("/etc/ssl/certs"),
+            default_mapper_timestamp: Flag(true),
+            default_mqtt_port: Port(DEFAULT_PORT),
+        }
+    );
+}