metasearch/src/web/search.rs
2023-12-20 23:17:39 -06:00

252 lines
8.4 KiB
Rust

use std::{collections::HashMap, net::SocketAddr};
use async_stream::stream;
use axum::{
body::Body,
extract::{ConnectInfo, Query},
http::{header, HeaderMap, StatusCode},
response::IntoResponse,
};
use bytes::Bytes;
use html_escape::{encode_text, encode_unquoted_attribute};
use crate::engines::{
self, Engine, EngineProgressUpdate, ProgressUpdateData, Response, SearchQuery,
};
fn render_beginning_of_html(query: &str) -> String {
format!(
r#"<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<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>
<link rel="search" type="application/opensearchdescription+xml" title="metasearch" href="/opensearch.xml"/>
</head>
<body>
<div class="results-container">
<main>
<form action="/search" method="get" class="search-form">
<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">
"#,
encode_text(query),
encode_unquoted_attribute(query)
)
}
fn render_end_of_html() -> String {
r#"</main></div></body></html>"#.to_string()
}
fn render_engine_list(engines: &[engines::Engine]) -> String {
let mut html = String::new();
for engine in engines {
html.push_str(&format!(
r#"<span class="engine-list-item">{engine}</span>"#,
engine = encode_text(&engine.id())
));
}
format!(r#"<div class="engine-list">{html}</div>"#)
}
fn render_search_result(result: &engines::SearchResult) -> String {
format!(
r#"<div class="search-result">
<a class="search-result-anchor" href="{url_attr}">
<span class="search-result-url" href="{url_attr}">{url}</span>
<h3 class="search-result-title">{title}</h3>
</a>
<p class="search-result-description">{desc}</p>
{engines_html}
</div>
"#,
url_attr = encode_unquoted_attribute(&result.url),
url = encode_text(&result.url),
title = encode_text(&result.title),
desc = encode_text(&result.description),
engines_html = render_engine_list(&result.engines.iter().copied().collect::<Vec<_>>())
)
}
fn render_featured_snippet(featured_snippet: &engines::FeaturedSnippet) -> String {
format!(
r#"<div class="featured-snippet">
<p class="search-result-description">{desc}</p>
<a class="search-result-anchor" href="{url_attr}">
<span class="search-result-url" href="{url_attr}">{url}</span>
<h3 class="search-result-title">{title}</h3>
</a>
{engines_html}
</div>
"#,
desc = encode_text(&featured_snippet.description),
url_attr = encode_unquoted_attribute(&featured_snippet.url),
url = encode_text(&featured_snippet.url),
title = encode_text(&featured_snippet.title),
engines_html = render_engine_list(&[featured_snippet.engine])
)
}
fn render_results(response: Response) -> String {
let mut html = String::new();
if let Some(infobox) = response.infobox {
html.push_str(&format!(
r#"<div class="infobox">{infobox_html}{engines_html}</div>"#,
infobox_html = &infobox.html,
engines_html = render_engine_list(&[infobox.engine])
));
}
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));
}
for result in &response.search_results {
html.push_str(&render_search_result(result));
}
html
}
fn render_engine_progress_update(
engine: Engine,
progress_update: &EngineProgressUpdate,
time_ms: u64,
) -> String {
let message = match progress_update {
EngineProgressUpdate::Requesting => "requesting",
EngineProgressUpdate::Downloading => "downloading",
EngineProgressUpdate::Parsing => "parsing",
EngineProgressUpdate::Done => "<span class=\"progress-update-done\">done</span>",
};
format!(r#"<span class="progress-update-time">{time_ms:>4}ms</span> {engine} {message}"#)
}
pub async fn route(
Query(params): Query<HashMap<String, String>>,
headers: HeaderMap,
ConnectInfo(addr): ConnectInfo<SocketAddr>,
) -> impl IntoResponse {
let query = params
.get("q")
.cloned()
.unwrap_or_default()
.trim()
.replace('\n', " ");
if query.is_empty() {
// redirect to index
return (
StatusCode::FOUND,
[
(header::LOCATION, "/"),
(header::CONTENT_TYPE, "text/html; charset=utf-8"),
],
Body::from("<a href=\"/\">No query provided, click here to go back to index</a>"),
);
}
let query = SearchQuery {
query,
request_headers: headers
.clone()
.into_iter()
.map(|(k, v)| {
(
k.map(|k| k.to_string()).unwrap_or_default(),
v.to_str().unwrap_or_default().to_string(),
)
})
.collect(),
ip: headers
// this could be exploited under some setups, but the ip is only used for the
// "what is my ip" answer so it doesn't really matter
.get("x-forwarded-for")
.map(|ip| ip.to_str().unwrap_or_default().to_string())
.unwrap_or_else(|| addr.ip().to_string()),
};
let s = stream! {
type R = Result<Bytes, eyre::Error>;
// the html is sent in three chunks (technically more if you count progress updates):
// 1) the beginning of the html, including the search bar
// 1.5) the progress updates
// 2) the results
// 3) the post-search infobox (usually not sent) + the end of the html
let first_part = render_beginning_of_html(&query);
// second part is in the loop
let mut third_part = String::new();
yield R::Ok(Bytes::from(first_part));
let (progress_tx, mut progress_rx) = tokio::sync::mpsc::unbounded_channel();
let search_future = tokio::spawn(async move { engines::search(query, progress_tx).await });
while let Some(progress_update) = progress_rx.recv().await {
match progress_update.data {
ProgressUpdateData::Engine { engine, update } => {
let progress_html = format!(
r#"<p class="progress-update">{}</p>"#,
render_engine_progress_update(engine, &update, progress_update.time_ms)
);
yield R::Ok(Bytes::from(progress_html));
},
ProgressUpdateData::Response(results) => {
let mut second_part = String::new();
second_part.push_str("</div>"); // close progress-updates
second_part.push_str("<style>.progress-updates{display:none}</style>");
second_part.push_str(&render_results(results));
yield Ok(Bytes::from(second_part));
},
ProgressUpdateData::PostSearchInfobox(infobox) => {
third_part.push_str(&format!(
r#"<div class="infobox postsearch-infobox">{infobox_html}{engines_html}</div>"#,
infobox_html = &infobox.html,
engines_html = render_engine_list(&[infobox.engine])
));
}
}
}
if let Err(e) = search_future.await? {
let error_html = format!(
r#"<h1>Error: {}</p>"#,
encode_text(&e.to_string())
);
yield R::Ok(Bytes::from(error_html));
return;
};
third_part.push_str(&render_end_of_html());
yield Ok(Bytes::from(third_part));
};
let stream = Body::from_stream(s);
(
StatusCode::OK,
[
(header::CONTENT_TYPE, "text/html; charset=utf-8"),
(header::TRANSFER_ENCODING, "chunked"),
],
stream,
)
}