Start to implement devices enrollment

central_backend/src/devices/devices_list.rs

@@ -0,0 +1,36 @@
+use crate::app_config::AppConfig;
+use crate::devices::device::{Device, DeviceId};
+use std::collections::HashMap;
+
+pub struct DevicesList(HashMap<DeviceId, Device>);
+
+impl DevicesList {
+    /// Load the list of devices. This method should be called only once during the whole execution
+    /// of the program
+    pub fn load() -> anyhow::Result<Self> {
+        let mut list = Self(HashMap::new());
+
+        for f in std::fs::read_dir(AppConfig::get().devices_config_path())? {
+            let f = f?.file_name();
+            let f = f.to_string_lossy();
+
+            let dev_id = match f.strip_suffix(".conf") {
+                Some(s) => DeviceId(s.to_string()),
+
+                // This is not a device configuration file
+                None => continue,
+            };
+
+            let device_conf = std::fs::read(AppConfig::get().device_config_path(&dev_id))?;
+
+            list.0.insert(dev_id, serde_json::from_slice(&device_conf)?);
+        }
+
+        Ok(list)
+    }
+
+    /// Check if a device with a given id exists or not
+    pub fn exists(&self, id: &DeviceId) -> bool {
+        self.0.contains_key(id)
+    }
+}