allow reading env variable from file

handy for docker secrets
also run cargo fmt

src/main.rs

@@ -1,12 +1,12 @@
 use json::JsonValue;
+use log::{debug, error, info};
 use regex::Regex;
 use std::env;
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::sync::oneshot;
 use tokio::sync::Semaphore;
 use tokio::time;
-use log::{debug, error, info};
 
 mod telegram_client;
 use telegram_client::*;
@@ -103,7 +103,7 @@ async fn handle_update(update: &JsonValue) {
         if maybe_chat_id.is_none() {
             // No idea what causes this but doesn't seem to hurt regular usage
             debug!("Encountered update with no message.chat.id object");
-            return
+            return;
         }
         let chat_id = maybe_chat_id.unwrap();
         let reply_to_message_id = message["message"]["reply_to_message"]["message_id"].as_i64();
@@ -206,12 +206,7 @@ async fn slow_poll(token: &str) -> ! {
 async fn main() {
     env_logger::init();
 
-    let maybe_token = env::var("TOKEN");
-    if maybe_token.is_err() {
-        error!("Environment variable 'TOKEN' not found");
-        std::process::exit(1);
-    }
-    let token = maybe_token.unwrap();
+    let token = get_config_value("TELEGRAM_TOKEN").expect("No TELEGRAM_TOKEN found");
 
     info!("Bot running!");
     slow_poll(&token).await;

src/telegram_client.rs

@@ -1,10 +1,10 @@
 use anyhow::Result;
 use json::JsonValue;
+use log::{debug, error};
 use reqwest::{multipart, Body};
 use serde::Serialize;
 use tokio::fs::File;
 use tokio_util::codec::{BytesCodec, FramedRead};
-use log::{debug, error};
 
 #[derive(Serialize)]
 pub struct DeleteMessage<'a> {
@@ -68,7 +68,11 @@ where
     let response = client.post(api_endpoint).json(payload).send().await?;
 
     if response.status() != reqwest::StatusCode::OK {
-        error!("Telegram API request {} failed with status code {:?}", method, response.status());
+        error!(
+            "Telegram API request {} failed with status code {:?}",
+            method,
+            response.status()
+        );
     }
 
     let body = response.text().await?;

src/util.rs

@@ -1,7 +1,8 @@
+use log::debug;
+use std::env;
 use std::fs;
 use std::process::{Command, Stdio};
 use uuid::Uuid;
-use log::debug;
 
 pub async fn download_video(url: String) -> Option<String> {
     let video_id = Uuid::new_v4();
@@ -25,9 +26,11 @@ pub async fn download_video(url: String) -> Option<String> {
         let output_path = std::fs::canonicalize(&file_path).unwrap();
         return Some(output_path.to_string_lossy().to_string());
     } else {
-        debug!("yt-dlp failed with\nstdout: {}\nstderr: {}",
-               String::from_utf8_lossy(&output.stdout),
-               String::from_utf8_lossy(&output.stderr));
+        debug!(
+            "yt-dlp failed with\nstdout: {}\nstderr: {}",
+            String::from_utf8_lossy(&output.stdout),
+            String::from_utf8_lossy(&output.stderr)
+        );
         return None;
     }
 }
@@ -74,3 +77,15 @@ pub fn delete_file(file: &str) -> Result<(), std::io::Error> {
     fs::remove_file(file)?;
     Ok(())
 }
+
+pub fn get_config_value(key: &str) -> Option<String> {
+    if let Ok(env_value) = env::var(key) {
+        if let Ok(file_content) = fs::read_to_string(&env_value) {
+            Some(file_content)
+        } else {
+            Some(env_value)
+        }
+    } else {
+        None
+    }
+}