feat: Dry run mode

The bot can run in dry-run mode, i.e. log that it has blocked users but
will not actually block them

Signed-off-by: Awiteb <a@4rs.nl>

src/config.rs

@@ -138,6 +138,9 @@ pub struct Exprs {
 /// forgejo-guard configuration
 #[derive(Deserialize)]
 pub struct Config {
+    /// Dry run, without banning the users
+    #[serde(default)]
+    pub dry_run:     bool,
     /// Configuration for the forgejo guard itself
     pub forgejo:     Forgejo,
     /// Configuration of the telegram bot

src/main.rs

@@ -40,6 +40,7 @@ async fn try_main() -> error::GuardResult<()> {
     let (sus_sender, sus_receiver) = sync::mpsc::channel::<forgejo_api::ForgejoUser>(100);
 
     tracing::info!("The instance: {}", config.forgejo.instance);
+    tracing::info!("Dry run: {}", config.dry_run);
     tracing::debug!("The config exprs: {:#?}", config.expressions);
 
     rust_i18n::set_locale(config.telegram.lang.as_str());

src/telegram_bot/callback_handler.rs

@@ -30,7 +30,8 @@ use teloxide::{
 
 use crate::{config::Config, forgejo_api};
 
-/// Inline keyboard with a single button that links to the Forgejo Guardian repository.
+/// Inline keyboard with a single button that links to the Forgejo Guardian
+/// repository.
 fn source_inline_keyboard(text: &str) -> InlineKeyboardMarkup {
     InlineKeyboardMarkup::new([[InlineKeyboardButton::new(
         text,
@@ -58,15 +59,17 @@ pub async fn callback_handler(
     match command {
         "b" => {
             // ban the user
-            let button_text = if forgejo_api::ban_user(
-                &Client::new(),
-                &config.forgejo.instance,
-                &config.forgejo.token,
-                data,
-            )
-            .await
-            .is_ok()
+            let button_text = if config.dry_run
+                || forgejo_api::ban_user(
+                    &Client::new(),
+                    &config.forgejo.instance,
+                    &config.forgejo.token,
+                    data,
+                )
+                .await
+                .is_ok()
             {
+                tracing::info!("Suspicious user @{data} has been blocked");
                 t!("messages.ban_success")
             } else {
                 t!("messages.ban_failed")

src/users_fetcher.rs

@@ -62,6 +62,10 @@ async fn check_new_user(
 ) {
     if let Some(re) = config.expressions.ban.is_match(&user) {
         tracing::info!("@{} has been banned because `{re}`", user.username);
+        if config.dry_run {
+            return;
+        }
+
         if let Err(err) = forgejo_api::ban_user(
             request_client,
             &config.forgejo.instance,