initial commit

.gitignore

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+/target

Cargo.toml

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+[package]
+name = "xkcdtg"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+reqwest = { version = "0.12.9", default-features = false, features = ["rustls-tls", "json"] }
+serde = { version = "1.0.215", features = ["derive"] }
+serde_json = "1.0.133"
+thiserror = "2.0.3"
+tokio = { version = "1.41.1", features = ["macros", "rt-multi-thread", "signal"] }
+
+[profile.release]
+codegen-units = 1
+lto = "fat"
+panic = "abort"

LICENSE

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+Copyright 2024 Andrey DarkCat09
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

src/main.rs

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+use std::sync::Arc;
+
+use reqwest::{Client, Url};
+use serde::Deserialize;
+use tokio::signal::unix::{signal, SignalKind};
+
+const BOT_URL: &str = "https://api.telegram.org/bot";
+/// Command to search for in a message text
+const COMMAND: &str = "/xkcd";
+/// Long polling timeout in seconds
+const POLL_TIMEOUT: &str = "300";
+/// Update types to receive (filtered out on tg backend)
+const POLL_TYPES: &str = r#"["message"]"#;
+
+/// Shared mutable state object
+#[derive(Debug)]
+struct State {
+    offset: u32,
+}
+
+/// Shared config object
+#[derive(Debug, Clone)]
+struct Config {
+    client: Client,
+    upd_url: Arc<Url>,
+    send_url: Arc<Url>,
+}
+
+/// Telegram Bot API response:
+/// these idiots use `{ok:true,response:...}` schema
+/// for some reason
+#[derive(Debug, Deserialize)]
+struct TgResponse {
+    result: Vec<TgUpdate>,
+}
+
+/// Telegram Bot API update event schema
+#[derive(Debug, Deserialize)]
+struct TgUpdate {
+    update_id: u32,
+    message: Option<TgMessage>,
+}
+
+/// Telegram Bot API message object schema
+#[derive(Debug, Deserialize)]
+struct TgMessage {
+    #[serde(rename = "message_thread_id")]
+    thread: Option<i32>,
+    chat: TgChat,
+    text: Option<String>,
+}
+
+/// Telegram Bot API chat object schema
+#[derive(Debug, Deserialize)]
+struct TgChat {
+    id: i64,
+    // #[serde(default)]
+    // is_forum: bool,
+}
+
+/// XKCD.com API comic info schema
+#[derive(Debug, Deserialize)]
+struct XkcdInfo {
+    alt: String,
+    img: String,
+}
+
+#[tokio::main]
+async fn main() -> std::io::Result<()> {
+    let cfg = {
+        let token = std::env::var("BOT_TOKEN").expect("invalid BOT_TOKEN env var value");
+        Config {
+            client: Client::new(),
+            upd_url: Url::parse(&format!("{BOT_URL}{token}/getUpdates"))
+                .unwrap()
+                .into(),
+            send_url: Url::parse(&format!("{BOT_URL}{token}/sendPhoto"))
+                .unwrap()
+                .into(),
+        }
+    };
+
+    let mut s = State { offset: 0 };
+
+    let mut sigint = signal(SignalKind::interrupt())?;
+    let mut sigterm = signal(SignalKind::terminate())?;
+
+    loop {
+        tokio::select! {
+            _ = sigint.recv() => {
+                break;
+            }
+            _ = sigterm.recv() => {
+                break;
+            }
+            out = handler(&cfg, &mut s) => {
+                match out {
+                    Ok(_) => {}
+                    Err(e) => {
+                        eprintln!("[handler] {:?}", e);
+                    }
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+async fn handler(cfg: &Config, s: &mut State) -> Result<(), reqwest::Error> {
+    let mut updates = cfg
+        .client
+        .get((*cfg.upd_url).clone())
+        .query(&[
+            ("offset", s.offset.to_string().as_str()),
+            ("timeout", POLL_TIMEOUT),
+            ("allowed_updates", POLL_TYPES),
+        ])
+        .send()
+        .await?
+        .json::<TgResponse>()
+        .await?
+        .result;
+
+    for u in &mut updates {
+        let Some(mut msg) = u.message.take() else {
+            continue;
+        };
+
+        let Some(text) = msg.text.take() else {
+            continue;
+        };
+
+        if !text.starts_with(COMMAND) {
+            continue;
+        }
+
+        let Some(comic_id) = text
+            .split_whitespace()
+            .skip(1)
+            .next()
+            .and_then(|id| id.parse::<u16>().ok())
+        else {
+            continue;
+        };
+
+        tokio::spawn(send_comic(cfg.clone(), msg, comic_id));
+    }
+
+    if let Some(u) = updates.last() {
+        s.offset = u.update_id + 1;
+    }
+
+    Ok(())
+}
+
+async fn send_comic(cfg: Config, msg: TgMessage, comic_id: u16) -> Result<(), reqwest::Error> {
+    let info = cfg
+        .client
+        .get(format!("https://xkcd.com/{}/info.0.json", comic_id))
+        .send()
+        .await?
+        .json::<XkcdInfo>()
+        .await?;
+
+    cfg.client
+        .post((*cfg.send_url).clone())
+        .form(&[
+            ("chat_id", msg.chat.id.to_string()),
+            (
+                "message_thread_id",
+                msg.thread
+                    .map(|t| t.to_string())
+                    .unwrap_or("null".to_owned()),
+            ),
+            ("photo", info.img),
+            ("caption", info.alt),
+        ])
+        .send()
+        .await?;
+
+    Ok(())
+}