From af79f6d2a35a1b03898f80e4b11253db60f9ea00 Mon Sep 17 00:00:00 2001
From: Edward Shen <code@eddie.sh>
Date: Wed, 1 May 2019 13:22:23 -0400
Subject: [PATCH] background updating works

---
 src/handlers.rs | 22 +++++++++++++++-------
 src/main.rs     |  3 ++-
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/src/handlers.rs b/src/handlers.rs
index 54b66ce..f8f314d 100644
--- a/src/handlers.rs
+++ b/src/handlers.rs
@@ -7,7 +7,7 @@ use actix_web::{
 use reqwest::{Client, Url, UrlError};
 
 use serde::Serialize;
-use std::sync::{Arc, MutexGuard, RwLock, RwLockWriteGuard};
+use std::sync::{Arc, RwLock};
 use tera::{Context, Tera};
 
 #[derive(Clone, Serialize, Default, Debug)]
@@ -45,13 +45,21 @@ pub fn json_endpoint(state: Data<State>) -> HttpResponse {
     HttpResponse::Ok().json(&state.statuses)
 }
 
-pub fn update_state(mut state: RwLockWriteGuard<QueryResults>) -> RwLockWriteGuard<QueryResults> {
-    if EpochTimestamp::now() - state.last_update >= state.refresh_time {
-        state.last_update = EpochTimestamp::now();
-        state.statuses = update_status(&state.config);
+pub fn update_state(state: State) {
+    let mut new_timestamp = None;
+    let mut new_statuses = None;
+    {
+        let read_state = state.read().unwrap();
+        if EpochTimestamp::now() - read_state.last_update >= read_state.refresh_time {
+            new_timestamp = Some(EpochTimestamp::now());
+            new_statuses = Some(update_status(&read_state.config));
+        }
+    }
+    if new_timestamp.is_some() {
+        let mut write_state = state.try_write().expect("Could not unlock");
+        write_state.last_update = new_timestamp.unwrap();
+        write_state.statuses = new_statuses.unwrap();
     }
-
-    state
 }
 
 fn update_status(config: &Config) -> Vec<Status> {
diff --git a/src/main.rs b/src/main.rs
index 864a3fa..ec03694 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -62,7 +62,8 @@ fn main() {
         tokio::spawn(
             Interval::new_interval(Duration::from_millis(5000))
                 .for_each(move |_| {
-                    let _ = update_state(clone_state.write().unwrap());
+                    let state = Arc::clone(&clone_state);
+                    update_state(state);
                     Ok(())
                 })
                 .map_err(|_| ()),