Support multiple config files in command args (#2)

Author: mullerch

src/config.rs

@@ -33,13 +33,17 @@ pub struct Configuration {
 }
 
 impl Configuration {
-    pub fn get(filename: &str) -> Result<Configuration, String> {
-        let toml_content = match fs::read_to_string(filename) {
-            Ok(v) => v,
-            Err(err) => return Err(format!("read config file error: {}", err).to_string()),
-        };
+    pub fn get(filenames: Vec<String>) -> Result<Configuration, String> {
+        let mut content: String = String::new();
+
+        for file_name in &filenames {
+            content.push_str(&match fs::read_to_string(file_name) {
+                Ok(v) => v,
+                Err(err) => return Err(format!("read config file error: {}", err).to_string()),
+            });
+        }
 
-        let config: Configuration = match toml::from_str(&toml_content) {
+        let config: Configuration = match toml::from_str(&content) {
             Ok(v) => v,
             Err(err) => return Err(format!("parse config file error: {}", err)),
         };

src/main.rs

@@ -29,13 +29,15 @@ fn main() {
                 .short("c")
                 .long("config")
                 .value_name("FILE")
+                .multiple(true)
+                .number_of_values(1)
                 .help("Path to configuration file")
                 .takes_value(true),
         )
         .get_matches();
 
-    let config_file = matches.value_of_lossy("config").unwrap();
-    let config = config::Configuration::get(&config_file).expect("read configuration error");
+    let config_files = matches.values_of_lossy("config").unwrap_or(vec![]);
+    let config = config::Configuration::get(config_files).expect("read configuration error");
     let log_level =
         log::Level::from_str(&config.udp_bridge.log_level).expect("parse log_level error");