Server structure

src/signature.rs

@@ -0,0 +1,21 @@
+use std::path::PathBuf;
+
+use ed25519_dalek::SigningKey;
+use rand::rngs::OsRng;
+
+pub async fn get() -> anyhow::Result<SigningKey> {
+    let private_key_path = PathBuf::from("private.key");
+
+    if !private_key_path.exists() {
+        let key = SigningKey::generate(&mut OsRng);
+        tokio::fs::write(private_key_path, &key.to_bytes()).await?;
+        Ok(key)
+    } else {
+        Ok(SigningKey::from_bytes(
+            &tokio::fs::read(private_key_path)
+                .await?
+                .try_into()
+                .map_err(|_| anyhow::anyhow!("Invalid private key"))?,
+        ))
+    }
+}