add instant answers

Cargo.lock

@@ -794,6 +794,7 @@ dependencies = [
  "eyre",
  "futures",
  "html-escape",
+ "regex",
  "reqwest",
  "scraper",
  "serde_json",

Cargo.toml

@@ -14,6 +14,7 @@ bytes = "1.5.0"
 eyre = "0.6.11"
 futures = "0.3.29"
 html-escape = "0.2.13"
+regex = "1.10.2"
 reqwest = { version = "0.11.23", default-features = false, features = [
     "rustls-tls",
 ] }

src/engines/answer.rs

@@ -0,0 +1,10 @@
+pub mod ip;
+pub mod useragent;
+
+macro_rules! regex {
+    ($re:literal $(,)?) => {{
+        static RE: std::sync::OnceLock<regex::Regex> = std::sync::OnceLock::new();
+        RE.get_or_init(|| regex::Regex::new($re).unwrap())
+    }};
+}
+pub(crate) use regex;

src/engines/answer/ip.rs

@@ -0,0 +1,13 @@
+use crate::engines::{EngineResponse, SearchQuery};
+
+use super::regex;
+
+pub fn request(_client: &reqwest::Client, query: &SearchQuery) -> EngineResponse {
+    if !regex!("^what('s|s| is) my ip").is_match(&query.query.to_lowercase()) {
+        return EngineResponse::new();
+    }
+
+    let ip = &query.ip;
+
+    EngineResponse::answer_html(format!("Your IP address is <b>{ip}</b>"))
+}

src/engines/answer/useragent.rs

@@ -0,0 +1,19 @@
+use crate::engines::{EngineResponse, SearchQuery};
+
+use super::regex;
+
+pub fn request(_client: &reqwest::Client, query: &SearchQuery) -> EngineResponse {
+    if !regex!("^what('s|s| is) my (user ?agent|ua)|ua|user ?agent$")
+        .is_match(&query.query.to_lowercase())
+    {
+        return EngineResponse::new();
+    }
+
+    let user_agent = query.request_headers.get("user-agent");
+
+    EngineResponse::answer_html(if let Some(user_agent) = user_agent {
+        format!("Your user agent is <b>{user_agent}</b>")
+    } else {
+        format!("You don't have a user agent")
+    })
+}

src/engines/mod.rs

@@ -1,5 +1,6 @@
 use std::{
     collections::{BTreeSet, HashMap},
+    ops::Deref,
     sync::LazyLock,
     time::Instant,
 };
@@ -9,18 +10,29 @@ use tokio::sync::mpsc;
 
 use self::search::{bing, brave, google};
 
+pub mod answer;
 pub mod search;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub enum Engine {
+    // search
     Google,
     Bing,
     Brave,
+    // answer
+    Useragent,
+    Ip,
 }
 
 impl Engine {
     pub fn all() -> &'static [Engine] {
-        &[Engine::Google, Engine::Bing, Engine::Brave]
+        &[
+            Engine::Google,
+            Engine::Bing,
+            Engine::Brave,
+            Engine::Useragent,
+            Engine::Ip,
+        ]
     }
 
     pub fn id(&self) -> &'static str {
@@ -28,6 +40,8 @@ impl Engine {
             Engine::Google => "google",
             Engine::Bing => "bing",
             Engine::Brave => "brave",
+            Engine::Useragent => "useragent",
+            Engine::Ip => "ip",
         }
     }
 
@@ -36,14 +50,17 @@ impl Engine {
             Engine::Google => 1.05,
             Engine::Bing => 1.,
             Engine::Brave => 1.25,
+            _ => 1.,
         }
     }
 
-    pub fn request(&self, client: &reqwest::Client, query: &str) -> reqwest::RequestBuilder {
+    pub fn request(&self, client: &reqwest::Client, query: &SearchQuery) -> RequestResponse {
         match self {
-            Engine::Google => google::request(client, query),
-            Engine::Bing => bing::request(client, query),
-            Engine::Brave => brave::request(client, query),
+            Engine::Google => google::request(client, query).into(),
+            Engine::Bing => bing::request(client, query).into(),
+            Engine::Brave => search::brave::request(client, query).into(),
+            Engine::Useragent => answer::useragent::request(client, query).into(),
+            Engine::Ip => answer::ip::request(client, query).into(),
         }
     }
 
@@ -52,6 +69,7 @@ impl Engine {
             Engine::Google => google::parse_response(body),
             Engine::Bing => bing::parse_response(body),
             Engine::Brave => brave::parse_response(body),
+            _ => eyre::bail!("engine {self:?} can't parse response"),
         }
     }
 
@@ -74,6 +92,36 @@ impl Engine {
     }
 }
 
+pub struct SearchQuery {
+    pub query: String,
+    pub request_headers: HashMap<String, String>,
+    pub ip: String,
+}
+
+impl Deref for SearchQuery {
+    type Target = str;
+
+    fn deref(&self) -> &Self::Target {
+        &self.query
+    }
+}
+
+pub enum RequestResponse {
+    Http(reqwest::RequestBuilder),
+    Instant(EngineResponse),
+}
+
+impl From<reqwest::RequestBuilder> for RequestResponse {
+    fn from(req: reqwest::RequestBuilder) -> Self {
+        Self::Http(req)
+    }
+}
+impl From<EngineResponse> for RequestResponse {
+    fn from(res: EngineResponse) -> Self {
+        Self::Instant(res)
+    }
+}
+
 #[derive(Debug)]
 pub struct EngineSearchResult {
     pub url: String,
@@ -88,10 +136,24 @@ pub struct EngineFeaturedSnippet {
     pub description: String,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Default)]
 pub struct EngineResponse {
     pub search_results: Vec<EngineSearchResult>,
     pub featured_snippet: Option<EngineFeaturedSnippet>,
+    pub answer_html: Option<String>,
+}
+
+impl EngineResponse {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    pub fn answer_html(html: String) -> Self {
+        Self {
+            answer_html: Some(html),
+            ..Default::default()
+        }
+    }
 }
 
 #[derive(Debug)]
@@ -122,7 +184,7 @@ impl ProgressUpdate {
 pub async fn search_with_client_and_engines(
     client: &reqwest::Client,
     engines: &[Engine],
-    query: &str,
+    query: &SearchQuery,
     progress_tx: mpsc::UnboundedSender<ProgressUpdate>,
 ) -> eyre::Result<Response> {
     let start_time = Instant::now();
@@ -137,29 +199,38 @@ pub async fn search_with_client_and_engines(
                 start_time,
             ))?;
 
-            let res = engine.request(client, query).send().await?;
+            let request_response = engine.request(client, query).into();
 
-            progress_tx.send(ProgressUpdate::new(
-                ProgressUpdateKind::Downloading,
-                engine,
-                start_time,
-            ))?;
+            let response = match request_response {
+                RequestResponse::Http(request) => {
+                    let res = request.send().await?;
 
-            let body = res.text().await?;
+                    progress_tx.send(ProgressUpdate::new(
+                        ProgressUpdateKind::Downloading,
+                        engine,
+                        start_time,
+                    ))?;
 
-            progress_tx.send(ProgressUpdate::new(
-                ProgressUpdateKind::Parsing,
-                engine,
-                start_time,
-            ))?;
+                    let body = res.text().await?;
 
-            let response = engine.parse_response(&body)?;
+                    progress_tx.send(ProgressUpdate::new(
+                        ProgressUpdateKind::Parsing,
+                        engine,
+                        start_time,
+                    ))?;
 
-            progress_tx.send(ProgressUpdate::new(
-                ProgressUpdateKind::Done,
-                engine,
-                start_time,
-            ))?;
+                    let response = engine.parse_response(&body)?;
+
+                    progress_tx.send(ProgressUpdate::new(
+                        ProgressUpdateKind::Done,
+                        engine,
+                        start_time,
+                    ))?;
+
+                    response
+                }
+                RequestResponse::Instant(response) => response,
+            };
 
             Ok((engine, response))
         });
@@ -209,11 +280,11 @@ pub async fn autocomplete_with_client_and_engines(
 static CLIENT: LazyLock<reqwest::Client> = LazyLock::new(|| reqwest::Client::new());
 
 pub async fn search(
-    query: &str,
+    query: SearchQuery,
     progress_tx: mpsc::UnboundedSender<ProgressUpdate>,
 ) -> eyre::Result<Response> {
     let engines = Engine::all();
-    search_with_client_and_engines(&CLIENT, &engines, query, progress_tx).await
+    search_with_client_and_engines(&CLIENT, &engines, &query, progress_tx).await
 }
 
 pub async fn autocomplete(query: &str) -> eyre::Result<Vec<String>> {
@@ -225,6 +296,7 @@ pub async fn autocomplete(query: &str) -> eyre::Result<Vec<String>> {
 pub struct Response {
     pub search_results: Vec<SearchResult>,
     pub featured_snippet: Option<FeaturedSnippet>,
+    pub answer: Option<Answer>,
 }
 
 #[derive(Debug)]
@@ -244,9 +316,16 @@ pub struct FeaturedSnippet {
     pub engine: Engine,
 }
 
+#[derive(Debug)]
+pub struct Answer {
+    pub html: String,
+    pub engine: Engine,
+}
+
 fn merge_engine_responses(responses: HashMap<Engine, EngineResponse>) -> Response {
     let mut search_results: Vec<SearchResult> = Vec::new();
     let mut featured_snippet: Option<FeaturedSnippet> = None;
+    let mut answer: Option<Answer> = None;
 
     for (engine, response) in responses {
         for (result_index, search_result) in response.search_results.into_iter().enumerate() {
@@ -299,6 +378,17 @@ fn merge_engine_responses(responses: HashMap<Engine, EngineResponse>) -> Respons
                 });
             }
         }
+
+        if let Some(engine_answer_html) = response.answer_html {
+            // if it has a higher weight than the current answer
+            let answer_weight = answer.as_ref().map(|s| s.engine.weight()).unwrap_or(0.);
+            if engine.weight() > answer_weight {
+                answer = Some(Answer {
+                    html: engine_answer_html,
+                    engine,
+                });
+            }
+        }
     }
 
     search_results.sort_by(|a, b| b.score.partial_cmp(&a.score).unwrap());
@@ -306,6 +396,7 @@ fn merge_engine_responses(responses: HashMap<Engine, EngineResponse>) -> Respons
     Response {
         search_results,
         featured_snippet,
+        answer,
     }
 }
 

src/parse.rs

@@ -176,5 +176,7 @@ pub(super) fn parse_html_response_with_opts(
     Ok(EngineResponse {
         search_results,
         featured_snippet,
+        // this field is used by instant answers, not normal search engines
+        answer_html: None,
     })
 }

src/web/assets/script.js

@@ -12,8 +12,6 @@ searchInputEl.addEventListener("input", async (e) => {
   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");

src/web/assets/style.css

@@ -97,6 +97,13 @@ h1 {
   margin-bottom: 1rem;
 }
 
+/* answer */
+.answer {
+  margin-bottom: 1rem;
+  border: 1px solid #234;
+  padding: 0.5rem;
+}
+
 /* progress update */
 .progress-updates {
   margin-bottom: 1rem;

src/web/autocomplete.rs

@@ -2,7 +2,7 @@ use std::collections::HashMap;
 
 use axum::{extract::Query, http::StatusCode, response::IntoResponse, Json};
 
-use crate::engines::{self, ProgressUpdate, ProgressUpdateKind, Response};
+use crate::engines;
 
 pub async fn route(Query(params): Query<HashMap<String, String>>) -> impl IntoResponse {
     let query = params

src/web/mod.rs

@@ -1,6 +1,8 @@
 pub mod autocomplete;
 pub mod search;
 
+use std::net::SocketAddr;
+
 use axum::{http::header, routing::get, Router};
 
 pub const BIND_ADDRESS: &str = "[::]:3000";
@@ -40,5 +42,10 @@ pub async fn run() {
     println!("Listening on {BIND_ADDRESS}");
 
     let listener = tokio::net::TcpListener::bind(BIND_ADDRESS).await.unwrap();
-    axum::serve(listener, app).await.unwrap();
+    axum::serve(
+        listener,
+        app.into_make_service_with_connect_info::<SocketAddr>(),
+    )
+    .await
+    .unwrap();
 }

src/web/search.rs

@@ -1,16 +1,16 @@
-use std::collections::HashMap;
+use std::{collections::HashMap, net::SocketAddr};
 
 use async_stream::stream;
 use axum::{
     body::Body,
-    extract::Query,
-    http::{header, StatusCode},
+    extract::{ConnectInfo, Query},
+    http::{header, HeaderMap, StatusCode},
     response::IntoResponse,
 };
 use bytes::Bytes;
 use html_escape::{encode_text, encode_unquoted_attribute};
 
-use crate::engines::{self, ProgressUpdate, ProgressUpdateKind, Response};
+use crate::engines::{self, ProgressUpdate, ProgressUpdateKind, Response, SearchQuery};
 
 fn render_beginning_of_html(query: &str) -> String {
     format!(
@@ -91,6 +91,13 @@ fn render_featured_snippet(featured_snippet: &engines::FeaturedSnippet) -> Strin
 
 fn render_results(response: Response) -> String {
     let mut html = String::new();
+    if let Some(answer) = response.answer {
+        html.push_str(&format!(
+            r#"<div class="answer">{answer_html}{engines_html}</div>"#,
+            answer_html = &answer.html,
+            engines_html = render_engine_list(&[answer.engine])
+        ));
+    }
     if let Some(featured_snippet) = response.featured_snippet {
         html.push_str(&render_featured_snippet(&featured_snippet));
     }
@@ -116,7 +123,11 @@ fn render_progress_update(progress_update: &ProgressUpdate) -> String {
     )
 }
 
-pub async fn route(Query(params): Query<HashMap<String, String>>) -> impl IntoResponse {
+pub async fn route(
+    Query(params): Query<HashMap<String, String>>,
+    headers: HeaderMap,
+    ConnectInfo(addr): ConnectInfo<SocketAddr>,
+) -> impl IntoResponse {
     let query = params
         .get("q")
         .cloned()
@@ -135,6 +146,20 @@ pub async fn route(Query(params): Query<HashMap<String, String>>) -> impl IntoRe
         );
     }
 
+    let query = SearchQuery {
+        query,
+        request_headers: headers
+            .into_iter()
+            .map(|(k, v)| {
+                (
+                    k.map(|k| k.to_string()).unwrap_or_default(),
+                    v.to_str().unwrap_or_default().to_string(),
+                )
+            })
+            .collect(),
+        ip: addr.ip().to_string(),
+    };
+
     let s = stream! {
         type R = Result<Bytes, eyre::Error>;
 
@@ -142,7 +167,7 @@ pub async fn route(Query(params): Query<HashMap<String, String>>) -> impl IntoRe
 
         let (progress_tx, mut progress_rx) = tokio::sync::mpsc::unbounded_channel();
 
-        let search_future = tokio::spawn(async move { engines::search(&query, progress_tx).await });
+        let search_future = tokio::spawn(async move { engines::search(query, progress_tx).await });
 
         while let Some(progress_update) = progress_rx.recv().await {
             let progress_html = format!(