Handle missing cookie file as connection failure

src/config.rs

@@ -176,8 +176,8 @@ struct StaticCookie {
 }
 
 impl CookieGetter for StaticCookie {
-    fn get(&self) -> String {
-        self.value.clone()
+    fn get(&self) -> Result<String> {
+        Ok(self.value.clone())
     }
 }
 
@@ -186,8 +186,9 @@ struct CookieFile {
 }
 
 impl CookieGetter for CookieFile {
-    fn get(&self) -> String {
-        read_cookie(&self.daemon_dir).unwrap()
+    fn get(&self) -> Result<String> {
+        read_cookie(&self.daemon_dir)
+            .chain_err(|| ErrorKind::Connection("no cookie found".to_owned()))
     }
 }
 

src/daemon.rs

@@ -128,7 +128,7 @@ impl MempoolEntry {
 }
 
 pub trait CookieGetter: Send + Sync {
-    fn get(&self) -> String;
+    fn get(&self) -> Result<String>;
 }
 
 struct Connection {
@@ -169,10 +169,10 @@ impl Connection {
     }
 
     fn send(&mut self, request: &str) -> Result<()> {
-        let cookie_b64 = base64::encode(&self.cookie_getter.get());
+        let cookie = &self.cookie_getter.get()?;
         let msg = format!(
             "POST / HTTP/1.1\nAuthorization: Basic {}\nContent-Length: {}\n\n{}",
-            cookie_b64,
+            base64::encode(cookie),
             request.len(),
             request,
         );