Add Telegram notification support (#7511)

automerge

watchtower/README.md

@@ -18,3 +18,20 @@ the following fields:
 * `test`: name of the sanity test that failed
 * `err`: exact sanity failure message
 
+<<<<<<< HEAD
+=======
+
+### Sanity failure push notification
+To receive a Slack, Discord and/or Telgram notification on sanity failure,
+define environment variables before running `solana-watchtower`:
+```
+export SLACK_WEBHOOK=...
+export DISCORD_WEBHOOK=...
+```
+
+Telgram requires the following two variables:
+```
+export TELEGRAM_BOT_TOKEN=...
+export TELEGRAM_CHAT_ID=...
+```
+>>>>>>> f33703aef... Add Telegram notification support

watchtower/src/notifier.rs

@@ -0,0 +1,71 @@
+use log::*;
+use reqwest::Client;
+use serde_json::json;
+use std::env;
+
+struct TelegramWebHook {
+    bot_token: String,
+    chat_id: String,
+}
+
+pub struct Notifier {
+    client: Client,
+    discord_webhook: Option<String>,
+    slack_webhook: Option<String>,
+    telegram_webhook: Option<TelegramWebHook>,
+}
+
+impl Notifier {
+    pub fn new() -> Self {
+        let discord_webhook = env::var("DISCORD_WEBHOOK")
+            .map_err(|_| {
+                info!("Discord notifications disabled");
+            })
+            .ok();
+        let slack_webhook = env::var("SLACK_WEBHOOK")
+            .map_err(|_| {
+                info!("Slack notifications disabled");
+            })
+            .ok();
+        let telegram_webhook = if let (Ok(bot_token), Ok(chat_id)) =
+            (env::var("TELEGRAM_BOT_TOKEN"), env::var("TELEGRAM_CHAT_ID"))
+        {
+            Some(TelegramWebHook { bot_token, chat_id })
+        } else {
+            info!("Telegram notifications disabled");
+            None
+        };
+
+        Notifier {
+            client: Client::new(),
+            discord_webhook,
+            slack_webhook,
+            telegram_webhook,
+        }
+    }
+
+    pub fn send(&self, msg: &str) {
+        if let Some(webhook) = &self.discord_webhook {
+            let data = json!({ "content": msg });
+            if let Err(err) = self.client.post(webhook).json(&data).send() {
+                warn!("Failed to send Discord message: {:?}", err);
+            }
+        }
+
+        if let Some(webhook) = &self.slack_webhook {
+            let data = json!({ "text": msg });
+            if let Err(err) = self.client.post(webhook).json(&data).send() {
+                warn!("Failed to send Slack message: {:?}", err);
+            }
+        }
+
+        if let Some(TelegramWebHook { chat_id, bot_token }) = &self.telegram_webhook {
+            let data = json!({ "chat_id": chat_id, "text": msg });
+            let url = format!("https://api.telegram.org/bot{}/sendMessage", bot_token);
+
+            if let Err(err) = self.client.post(&url).json(&data).send() {
+                warn!("Failed to send Telegram message: {:?}", err);
+            }
+        }
+    }
+}