hash the post

src/routes/blog.rs

@@ -1,4 +1,9 @@
-use ::rss::{Category, Channel, Image, Item};
+use std::{
+    collections::hash_map::DefaultHasher,
+    hash::{Hash, Hasher},
+};
+
+use ::rss::{Category, Channel, Guid, Image, Item};
 use actix_web::{dev::ConnectionInfo, get, web, HttpRequest, HttpResponse, Responder};
 use cached::proc_macro::once;
 use chrono::{DateTime, Datelike, Local, NaiveDateTime, Utc};
@@ -56,6 +61,17 @@ struct Post {
     desc: Option<String>,
 }
 
+impl Hash for Post {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        let blog_dir = "data/blog";
+        let ext = ".md";
+
+        if let Some(file) = read_file(&format!("{blog_dir}/{}{ext}", self.url)) {
+            file.content.hash(state)
+        }
+    }
+}
+
 fn get_posts(location: &str) -> Vec<Post> {
     let entries = match std::fs::read_dir(location) {
         Ok(res) => res
@@ -207,6 +223,14 @@ fn build_rss(config: Config, info: ConnectionInfo) -> String {
                 title: Some(p.title.to_owned()),
                 link: Some(format!("{}/blog/p/{}", link_to_site, p.url)),
                 description: p.desc.to_owned(),
+                guid: Some(Guid {
+                    value: format!("urn:hash:{}", {
+                        let mut hasher = DefaultHasher::new();
+                        p.hash(&mut hasher);
+                        hasher.finish()
+                    }),
+                    permalink: false,
+                }),
                 pub_date: Some(
                     NaiveDateTime::parse_from_str(
                         &format!("{}-{}-{} 13:12:00", p.date.day, p.date.month, p.date.year),