Remove cache and send HEAD before parsing title

src/main.rs

@@ -1,5 +1,3 @@
-use std::collections::HashMap;
-
 use futures::prelude::*;
 use htmlescape::decode_html;
 use irc::client::prelude::*;
@@ -83,7 +81,7 @@ async fn main() -> anyhow::Result<()> {
         let title_regex = Regex::new(r"(?<=<title>)(.*)(?=</title>)").unwrap();
         let spotify_regex = Regex::new(r"(?:https?|spotify):(?://open\.spotify\.com/)?(track|artist|album|playlist)[/:]([a-zA-Z0-9]*)").unwrap();
 
-        let mut cache: HashMap<String, String> = HashMap::new();
+       let hclient = reqwest::Client::new();
 
         while let Some(message) = stream.next().await.transpose()? {
             if vlog { print!("[IRC] {}", message) }
@@ -101,18 +99,32 @@ async fn main() -> anyhow::Result<()> {
                     }
                 } else if let Some(m) = url_regex.find(&message) {
                     let url = &message[m.0..m.1];
-                    if let Some(entry) = cache.get(&url.to_string()) {
-                        client.send_privmsg(&channel, format!("\x039[Title]\x0311 {}", entry))?;
-                        continue;
+                    match hclient.head(url).send().await {
+                        Ok(o) => {
+                            let headers = o.headers();
+                            let ctype = match headers.get("Content-Type") {
+                                Some(c) => match c.to_str() {
+                                    Ok(s) => s,
+                                    Err(_) => continue,
+                                },
+                                None => continue,
+                            };
+                            if !ctype.starts_with("text/html") {
+                                continue;
+                            }
+                        },
+                        Err(e) => {
+                            println!("[Title] Error! {}", e);
+                            continue;
+                        }
                     }
-                    match reqwest::get(url).await {
+                    match hclient.get(url).send().await {
                         Ok(o) => {
                             let body = o.text().await?;
                             if let Some(tm) = title_regex.find(&body) {
                                 let title_match = &body[tm.0..tm.1];
                                 let result = decode_html(title_match).unwrap_or_else(|_| title_match.to_string());
                                 client.send_privmsg(&channel, format!("\x039[Title]\x0311 {}", result))?;
-                                cache.insert(url.to_string(), result.to_string());
                             }
                         }
                         Err(e) => println!("[Title] Error! {}", e)