adding IBEJI_HOME env var for loading the invehicle digital twin config file

README.md

@@ -219,8 +219,10 @@ Make sure that you replace "{repo-root-dir}" with the repository root directory
 ---- provider_settings.yaml ----<br>
 `provider_authority: "0.0.0.0:4010"`<br>
 `invehicle_digital_twin_uri: "http://0.0.0.0:5010"`<br><br>
-1. In the top window, run:<br><br>
+1. In the top window, run (config files will be loaded from the current working directory):<br><br>
 `./invehicle-digital-twin`<br>
+Use the `IBEJI_HOME` environment variable to load configuration files from a specific directory: <br>
+`IBEJI_HOME=/etc/ibeji ./invehicle-digital-twin`<br>
 1. In the middle window, run:<br><br>
 `./seat-massager-provider`<br>
 1. In the bottom window, run:<br><br>

core/common/src/utils.rs

@@ -13,6 +13,8 @@ use strum_macros::Display;
 use tokio::time::{sleep, Duration};
 use tonic::{Request, Status};
 
+const IBEJI_HOME_VAR_NAME: &str = "IBEJI_HOME";
+
 /// An identifier used when discovering a service through Chariott.
 #[derive(Debug, Deserialize)]
 pub struct ServiceIdentifier {
@@ -41,8 +43,13 @@ pub fn load_settings<T>(config_filename: &str) -> Result<T, ConfigError>
 where
     T: for<'de> serde::Deserialize<'de>,
 {
+    let config_filename_path = match std::env::var(IBEJI_HOME_VAR_NAME) {
+        Ok(s) => format!("{}/{}", s, config_filename),
+        _ => config_filename.to_owned()
+    };
+
     let config =
-        Config::builder().add_source(File::new(config_filename, FileFormat::Yaml)).build()?;
+        Config::builder().add_source(File::new(config_filename_path.as_str(), FileFormat::Yaml)).build()?;
 
     config.try_deserialize()
 }

core/invehicle-digital-twin/src/invehicle_digital_twin_config.rs

@@ -2,7 +2,7 @@
 // Licensed under the MIT license.
 // SPDX-License-Identifier: MIT
 
-use config::{Config, File, FileFormat};
+use common::utils;
 use serde_derive::Deserialize;
 
 const CONFIG_FILENAME: &str = "invehicle_digital_twin_settings";
@@ -15,10 +15,7 @@ pub struct Settings {
 
 /// Load the settings.
 pub fn load_settings() -> Settings {
-    let config =
-        Config::builder().add_source(File::new(CONFIG_FILENAME, FileFormat::Yaml)).build().unwrap();
-
-    let settings: Settings = config.try_deserialize().unwrap();
+    let settings = utils::load_settings(CONFIG_FILENAME).unwrap();
 
     settings
 }