Configuration can now be assembled from a directory.

src/config.rs

@@ -1,6 +1,7 @@
 extern crate serde_derive;
 extern crate toml;
 use crate::lib::errors;
+use std::collections::BTreeMap;
 use std::collections::HashMap;
 use std::env;
 use std::net;
@@ -67,7 +68,11 @@ impl Config {
             p.push(&args[1]);
         }
 
-        let fd = fs::read_to_string(p).await.unwrap();
+        let fd = match p.is_dir() {
+            false => fs::read_to_string(p).await.unwrap(),
+            true => merge_directory(p).await.unwrap()
+        };
+
         let mut config: Config = match toml::from_str(&fd) {
             Ok(c) => c,
             Err(e) => return Err(Box::new(e)),
@@ -125,3 +130,23 @@ impl Config {
         map
     }
 }
+
+async fn merge_directory(dir_name: path::PathBuf) -> std::io::Result<String> {
+    let mut entries = fs::read_dir(dir_name).await?;
+    let mut chunks = BTreeMap::new();
+
+    /*
+     * Directory entries are first read and sorted with their filename.
+     * Order is important because keys must precede server tables.
+     */
+    while let Some(entry) = entries.next_entry().await? {
+        let path = entry.file_name();
+        if path.to_str().unwrap().ends_with(".toml") {
+            if entry.file_type().await.unwrap().is_file() {
+                chunks.insert(path, fs::read_to_string(&entry.path()).await?);
+            }
+        }
+    }
+
+    Ok(chunks.values().fold(String::new(), |mut acc, chunk| { acc.push_str(chunk); acc }))
+}