add basic autocomplete

Cargo.lock

@@ -796,6 +796,7 @@ dependencies = [
  "html-escape",
  "reqwest",
  "scraper",
+ "serde_json",
  "tokio",
  "tokio-stream",
  "tracing-subscriber",

Cargo.toml

@@ -18,6 +18,7 @@ reqwest = { version = "0.11.23", default-features = false, features = [
     "rustls-tls",
 ] }
 scraper = "0.18.1"
+serde_json = "1.0.108"
 tokio = { version = "1.35.0", features = ["full"] }
 tokio-stream = "0.1.14"
 tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }

README

@@ -0,0 +1 @@
+a cute metasearch engine

src/engines/mod.rs

@@ -1,6 +1,5 @@
 use std::{
     collections::{BTreeSet, HashMap},
-    fmt,
     sync::LazyLock,
     time::Instant,
 };
@@ -24,7 +23,7 @@ impl Engine {
         &[Engine::Google, Engine::Bing, Engine::Brave]
     }
 
-    pub fn name(&self) -> &'static str {
+    pub fn id(&self) -> &'static str {
         match self {
             Engine::Google => "google",
             Engine::Bing => "bing",
@@ -32,6 +31,14 @@ impl Engine {
         }
     }
 
+    pub fn weight(&self) -> f64 {
+        match self {
+            Engine::Google => 1.05,
+            Engine::Bing => 1.,
+            Engine::Brave => 1.25,
+        }
+    }
+
     pub fn request(&self, client: &reqwest::Client, query: &str) -> reqwest::RequestBuilder {
         match self {
             Engine::Google => google::request(client, query),
@@ -48,11 +55,21 @@ impl Engine {
         }
     }
 
-    pub fn weight(&self) -> f64 {
+    pub fn request_autocomplete(
+        &self,
+        client: &reqwest::Client,
+        query: &str,
+    ) -> Option<reqwest::RequestBuilder> {
         match self {
-            Engine::Google => 1.05,
-            Engine::Bing => 1.,
-            Engine::Brave => 1.25,
+            Engine::Google => Some(google::request_autocomplete(client, query)),
+            _ => None,
+        }
+    }
+
+    pub fn parse_autocomplete_response(&self, body: &str) -> eyre::Result<Vec<String>> {
+        match self {
+            Engine::Google => google::parse_autocomplete_response(body),
+            _ => Ok(Vec::new()),
         }
     }
 }
@@ -102,25 +119,6 @@ impl ProgressUpdate {
     }
 }
 
-impl fmt::Display for ProgressUpdate {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let message = match self.kind {
-            ProgressUpdateKind::Requesting => "requesting",
-            ProgressUpdateKind::Downloading => "downloading",
-            ProgressUpdateKind::Parsing => "parsing",
-            ProgressUpdateKind::Done => "<b>done</b>",
-        };
-
-        write!(
-            f,
-            r#"<span class="progress-update-time">{time:>4}ms</span> {engine} {message}"#,
-            time = self.time,
-            message = message,
-            engine = self.engine.name()
-        )
-    }
-}
-
 pub async fn search_with_client_and_engines(
     client: &reqwest::Client,
     engines: &[Engine],
@@ -179,6 +177,35 @@ pub async fn search_with_client_and_engines(
     Ok(merge_engine_responses(responses))
 }
 
+pub async fn autocomplete_with_client_and_engines(
+    client: &reqwest::Client,
+    engines: &[Engine],
+    query: &str,
+) -> eyre::Result<Vec<String>> {
+    let mut requests = Vec::new();
+    for engine in engines {
+        if let Some(request) = engine.request_autocomplete(client, query) {
+            requests.push(async {
+                let res = request.send().await?;
+                let body = res.text().await?;
+                let response = engine.parse_autocomplete_response(&body)?;
+                Ok((*engine, response))
+            });
+        }
+    }
+
+    let mut autocomplete_futures = Vec::new();
+    for request in requests {
+        autocomplete_futures.push(request);
+    }
+
+    let autocomplete_results_result: eyre::Result<HashMap<_, _>> =
+        join_all(autocomplete_futures).await.into_iter().collect();
+    let autocomplete_results = autocomplete_results_result?;
+
+    Ok(merge_autocomplete_responses(autocomplete_results))
+}
+
 static CLIENT: LazyLock<reqwest::Client> = LazyLock::new(|| reqwest::Client::new());
 
 pub async fn search(
@@ -189,6 +216,11 @@ pub async fn search(
     search_with_client_and_engines(&CLIENT, &engines, query, progress_tx).await
 }
 
+pub async fn autocomplete(query: &str) -> eyre::Result<Vec<String>> {
+    let engines = Engine::all();
+    autocomplete_with_client_and_engines(&CLIENT, &engines, query).await
+}
+
 #[derive(Debug)]
 pub struct Response {
     pub search_results: Vec<SearchResult>,
@@ -276,3 +308,36 @@ fn merge_engine_responses(responses: HashMap<Engine, EngineResponse>) -> Respons
         featured_snippet,
     }
 }
+
+pub struct AutocompleteResult {
+    pub query: String,
+    pub score: f64,
+}
+
+fn merge_autocomplete_responses(responses: HashMap<Engine, Vec<String>>) -> Vec<String> {
+    let mut autocomplete_results: Vec<AutocompleteResult> = Vec::new();
+
+    for (engine, response) in responses {
+        for (result_index, autocomplete_result) in response.into_iter().enumerate() {
+            // position 1 has a score of 1, position 2 has a score of 0.5, position 3 has a score of 0.33, etc.
+            let base_result_score = 1. / (result_index + 1) as f64;
+            let result_score = base_result_score * engine.weight();
+
+            if let Some(existing_result) = autocomplete_results
+                .iter_mut()
+                .find(|r| r.query == autocomplete_result)
+            {
+                existing_result.score += result_score;
+            } else {
+                autocomplete_results.push(AutocompleteResult {
+                    query: autocomplete_result,
+                    score: result_score,
+                });
+            }
+        }
+    }
+
+    autocomplete_results.sort_by(|a, b| b.score.partial_cmp(&a.score).unwrap());
+
+    autocomplete_results.into_iter().map(|r| r.query).collect()
+}

src/engines/search/bing.rs

@@ -38,7 +38,7 @@ pub fn parse_response(body: &str) -> eyre::Result<EngineResponse> {
                     .unwrap_or_default();
                 clean_url(url)
             })))
-            .description(".b_caption > p, p.b_algoSlug"),
+            .description(".b_caption > p, p.b_algoSlug, .b_caption .ipText"),
     )
 }
 

src/engines/search/brave.rs

@@ -22,6 +22,6 @@ pub fn parse_response(body: &str) -> eyre::Result<EngineResponse> {
             .result("#results > .snippet[data-pos]:not(.standalone)")
             .title(".url")
             .href("a")
-            .description(".snippet-content"),
+            .description(".snippet-content, .video-snippet > .snippet-description"),
     )
 }

src/engines/search/google.rs

@@ -45,6 +45,40 @@ pub fn parse_response(body: &str) -> eyre::Result<EngineResponse> {
     )
 }
 
+pub fn request_autocomplete(client: &reqwest::Client, query: &str) -> reqwest::RequestBuilder {
+    client
+        .get(
+            Url::parse_with_params(
+                "https://suggestqueries.google.com/complete/search",
+                &[
+                    ("output", "firefox"),
+                    ("client", "firefox"),
+                    ("hl", "US-en"),
+                    ("q", query),
+                ],
+            )
+            .unwrap(),
+        )
+        .header(
+            "User-Agent",
+            "Mozilla/5.0 (X11; Linux x86_64; rv:121.0) Gecko/20100101 Firefox/121.0",
+        )
+}
+
+pub fn parse_autocomplete_response(body: &str) -> eyre::Result<Vec<String>> {
+    let res = serde_json::from_str::<Vec<serde_json::Value>>(body)?;
+    Ok(res
+        .into_iter()
+        .nth(1)
+        .unwrap_or_default()
+        .as_array()
+        .cloned()
+        .unwrap_or_default()
+        .into_iter()
+        .map(|v| v.as_str().unwrap_or_default().to_string())
+        .collect())
+}
+
 fn clean_url(url: &str) -> eyre::Result<String> {
     if url.starts_with("/url?q=") {
         // get the q param

src/normalize.rs

@@ -12,6 +12,9 @@ pub fn normalize_url(url: &str) -> eyre::Result<String> {
         url.set_scheme("https").unwrap();
     }
 
+    // remove fragment
+    url.set_fragment(None);
+
     // remove trailing slash
     let path = url.path().to_string();
     if let Some(path) = path.strip_suffix('/') {

src/web/assets/index.html

@@ -5,12 +5,13 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>metasearch</title>
     <link rel="stylesheet" href="/style.css">
+    <script src="/script.js" defer></script>
 </head>
 <body>
     <div class="main-container">
         <h1>metasearch</h1>
         <form action="/search" method="get">
-            <input type="text" name="q" placeholder="Search" class="search-input" autofocus>
+            <input type="text" name="q" placeholder="Search" id="search-input" autofocus onfocus="this.select()" autocomplete="off">
             <input type="submit" value="Search">
         </form>
     </div>

src/web/assets/script.js

@@ -0,0 +1,23 @@
+// add a datalist after the search input
+const searchInputEl = document.getElementById("search-input");
+const datalistEl = document.createElement("datalist");
+datalistEl.id = "search-input-datalist";
+searchInputEl.setAttribute("list", datalistEl.id);
+searchInputEl.insertAdjacentElement("afterend", datalistEl);
+
+// update the datalist options on input
+searchInputEl.addEventListener("input", async (e) => {
+  const value = e.target.value;
+
+  const res = await fetch(`/autocomplete?q=${value}`).then((res) => res.json());
+  const options = res[1];
+
+  console.log(options);
+
+  datalistEl.innerHTML = "";
+  options.forEach((option) => {
+    const optionEl = document.createElement("option");
+    optionEl.value = option;
+    datalistEl.appendChild(optionEl);
+  });
+});

src/web/assets/style.css

@@ -46,7 +46,7 @@ h1 {
 .search-form {
   margin-bottom: 1rem;
 }
-.search-input {
+#search-input {
   width: 20em;
 }
 
@@ -111,3 +111,7 @@ h1 {
 .progress-update-time {
   opacity: 0.5;
 }
+.progress-update-done {
+  color: #7fd962;
+  font-weight: bold;
+}

src/web/autocomplete.rs

@@ -0,0 +1,24 @@
+use std::collections::HashMap;
+
+use axum::{extract::Query, http::StatusCode, response::IntoResponse, Json};
+
+use crate::engines::{self, ProgressUpdate, ProgressUpdateKind, Response};
+
+pub async fn route(Query(params): Query<HashMap<String, String>>) -> impl IntoResponse {
+    let query = params
+        .get("q")
+        .cloned()
+        .unwrap_or_default()
+        .trim()
+        .replace('\n', " ");
+
+    let res = match engines::autocomplete(&query).await {
+        Ok(res) => res,
+        Err(err) => {
+            eprintln!("Error: {}", err);
+            return (StatusCode::INTERNAL_SERVER_ERROR, Json((query, vec![])));
+        }
+    };
+
+    (StatusCode::OK, Json((query, res)))
+}

src/web/mod.rs

@@ -1,3 +1,4 @@
+pub mod autocomplete;
 pub mod search;
 
 use axum::{http::header, routing::get, Router};
@@ -24,7 +25,17 @@ pub async fn run() {
                 )
             }),
         )
-        .route("/search", get(search::route));
+        .route(
+            "/script.js",
+            get(|| async {
+                (
+                    [(header::CONTENT_TYPE, "text/javascript; charset=utf-8")],
+                    include_str!("assets/script.js"),
+                )
+            }),
+        )
+        .route("/search", get(search::route))
+        .route("/autocomplete", get(autocomplete::route));
 
     println!("Listening on {BIND_ADDRESS}");
 

src/web/search.rs

@@ -10,7 +10,7 @@ use axum::{
 use bytes::Bytes;
 use html_escape::{encode_text, encode_unquoted_attribute};
 
-use crate::engines::{self, Response};
+use crate::engines::{self, ProgressUpdate, ProgressUpdateKind, Response};
 
 fn render_beginning_of_html(query: &str) -> String {
     format!(
@@ -21,11 +21,12 @@ fn render_beginning_of_html(query: &str) -> String {
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>{} - metasearch</title>
     <link rel="stylesheet" href="/style.css">
+    <script src="/script.js" defer></script>
 </head>
 <body>
     <main>
     <form action="/search" method="get" class="search-form">
-        <input type="text" name="q" placeholder="Search" value="{}" class="search-input" autofocus>
+        <input type="text" name="q" placeholder="Search" value="{}" id="search-input" autofocus onfocus="this.select()" autocomplete="off">
         <input type="submit" value="Search">
     </form>
     <div class="progress-updates">
@@ -44,7 +45,7 @@ fn render_engine_list(engines: &[engines::Engine]) -> String {
     for engine in engines {
         html.push_str(&format!(
             r#"<span class="engine-list-item">{engine}</span>"#,
-            engine = encode_text(&engine.name())
+            engine = encode_text(&engine.id())
         ));
     }
     format!(r#"<div class="engine-list">{html}</div>"#)
@@ -99,6 +100,22 @@ fn render_results(response: Response) -> String {
     html
 }
 
+fn render_progress_update(progress_update: &ProgressUpdate) -> String {
+    let message: &str = match progress_update.kind {
+        ProgressUpdateKind::Requesting => "requesting",
+        ProgressUpdateKind::Downloading => "downloading",
+        ProgressUpdateKind::Parsing => "parsing",
+        ProgressUpdateKind::Done => "<span class=\"progress-update-done\">done</span>",
+    };
+
+    format!(
+        r#"<span class="progress-update-time">{time:>4}ms</span> {engine} {message}"#,
+        time = progress_update.time,
+        message = message,
+        engine = progress_update.engine.id()
+    )
+}
+
 pub async fn route(Query(params): Query<HashMap<String, String>>) -> impl IntoResponse {
     let query = params
         .get("q")
@@ -129,7 +146,8 @@ pub async fn route(Query(params): Query<HashMap<String, String>>) -> impl IntoRe
 
         while let Some(progress_update) = progress_rx.recv().await {
             let progress_html = format!(
-                r#"<p class="progress-update">{progress_update}</p>"#
+                r#"<p class="progress-update">{}</p>"#,
+                render_progress_update(&progress_update)
             );
             yield R::Ok(Bytes::from(progress_html));
         }