[CIT-502] Default software plugin support (#386)

* [CIT-502] Default software plugin support

4 files changed, 54 insertions, 0 deletions

diff --git a/tedge_config/src/settings.rs b/tedge_config/src/settings.rs
index cff9541e..438cead8 100644
--- a/tedge_config/src/settings.rs
+++ b/tedge_config/src/settings.rs
@@ -158,3 +158,17 @@ impl ConfigSetting for MqttPortSetting {
 
     type Value = Port;
 }
+
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub struct SoftwarePluginDefaultSetting;
+
+impl ConfigSetting for SoftwarePluginDefaultSetting {
+    const KEY: &'static str = "software.plugin.default";
+
+    const DESCRIPTION: &'static str = concat!(
+        "The default software plugin to be used for software management on the device",
+        "Example: apt"
+    );
+
+    type Value = String;
+}
diff --git a/tedge_config/src/tedge_config.rs b/tedge_config/src/tedge_config.rs
index ef1766dd..cbfacaa6 100644
--- a/tedge_config/src/tedge_config.rs
+++ b/tedge_config/src/tedge_config.rs
@@ -244,6 +244,32 @@ impl ConfigSettingAccessor<MqttPortSetting> for TEdgeConfig {
     }
 }
 
+impl ConfigSettingAccessor<SoftwarePluginDefaultSetting> for TEdgeConfig {
+    fn query(&self, _setting: SoftwarePluginDefaultSetting) -> ConfigSettingResult<String> {
+        self.data
+            .software
+            .default_plugin_type
+            .clone()
+            .ok_or(ConfigSettingError::ConfigNotSet {
+                key: SoftwarePluginDefaultSetting::KEY,
+            })
+    }
+
+    fn update(
+        &mut self,
+        _setting: SoftwarePluginDefaultSetting,
+        value: String,
+    ) -> ConfigSettingResult<()> {
+        self.data.software.default_plugin_type = Some(value);
+        Ok(())
+    }
+
+    fn unset(&mut self, _setting: SoftwarePluginDefaultSetting) -> ConfigSettingResult<()> {
+        self.data.software.default_plugin_type = None;
+        Ok(())
+    }
+}
+
 /// Generic extension trait implementation for all `ConfigSetting`s of `TEdgeConfig`
 /// that provide `TryFrom`/`TryInto` implementations for `String`.
 impl<T, E, F> ConfigSettingAccessorStringExt<T> for TEdgeConfig
diff --git a/tedge_config/src/tedge_config_dto.rs b/tedge_config/src/tedge_config_dto.rs
index 2e9579ec..faabd8d4 100644
--- a/tedge_config/src/tedge_config_dto.rs
+++ b/tedge_config/src/tedge_config_dto.rs
@@ -19,6 +19,9 @@ pub(crate) struct TEdgeConfigDto {
 
     #[serde(default)]
     pub(crate) mqtt: MqttConfigDto,
+
+    #[serde(default)]
+    pub(crate) software: SoftwareConfigDto,
 }
 
 /// Represents the device specific configurations defined in the [device] section
@@ -73,3 +76,9 @@ pub(crate) struct AzureConfigDto {
 pub(crate) struct MqttConfigDto {
     pub(crate) port: Option<u16>,
 }
+
+#[derive(Debug, Default, Deserialize, Serialize)]
+#[serde(deny_unknown_fields)]
+pub(crate) struct SoftwareConfigDto {
+    pub(crate) default_plugin_type: Option<String>,
+}
diff --git a/tedge_config/src/tedge_config_repository.rs b/tedge_config/src/tedge_config_repository.rs
index 790efb29..433d3013 100644
--- a/tedge_config/src/tedge_config_repository.rs
+++ b/tedge_config/src/tedge_config_repository.rs
@@ -5,6 +5,7 @@ use tedge_utils::fs::atomically_write_file_sync;
 
 /// TEdgeConfigRepository is resposible for loading and storing TEdgeConfig entities.
 ///
+#[derive(Debug)]
 pub struct TEdgeConfigRepository {
     config_location: TEdgeConfigLocation,
     config_defaults: TEdgeConfigDefaults,
@@ -59,6 +60,10 @@ impl TEdgeConfigRepository {
         }
     }
 
+    pub fn get_config_location(&self) -> &TEdgeConfigLocation {
+        &self.config_location
+    }
+
     /// Parse the configuration file at the provided `path` and create a `TEdgeConfig` out of it
     ///
     /// #Arguments