add sqlite max connections as a parameter

src/bot.rs

@@ -160,9 +160,8 @@ async fn deadline_from_datetime(dt: NaiveDateTime) -> Instant {
     Instant::now() + duration
 }
 
-/// Periodically (every second) check for new reminders.
-/// Send and delete one-time reminders if time has come.
-/// Send cron reminders if time has come and update next reminder time.
+/// Wait for the next reminder to send or some change in the database.
+/// Send and update/delete reminders.
 async fn poll_reminders(db: Arc<Database>, bot: Bot) {
     const DEFAULT_CHECK_INTERVAL: TimeDelta = TimeDelta::seconds(60);
 

src/cli.rs

@@ -21,6 +21,15 @@ pub(crate) struct Cli {
     pub(crate) database: PathBuf,
     #[arg(short, long, value_name = "BOT TOKEN", env = "BOT_TOKEN")]
     pub(crate) token: String,
+    #[arg(
+        short,
+        long,
+        env = "SQLITE_MAX_CONNECTIONS",
+        value_name = "NUMBER",
+        help = "Maximum number of connections to the SQLite database",
+        default_value = "1"
+    )]
+    pub(crate) sqlite_max_connections: u32,
 }
 
 pub(crate) fn parse_args() -> Cli {

src/db.rs

@@ -1,5 +1,6 @@
 use std::path::Path;
 
+use crate::cli::CLI;
 use crate::entity::{cron_reminder, reminder, user_timezone};
 use crate::generic_reminder;
 use crate::migration::{DbErr, Migrator, MigratorTrait};
@@ -45,7 +46,7 @@ impl From<std::io::Error> for Error {
 async fn get_db_pool(db_path: &Path) -> Result<DatabaseConnection, Error> {
     let db_str = format!("sqlite:{}?mode=rwc", db_path.display());
     let mut opts = ConnectOptions::new(&db_str);
-    opts.max_connections(100);
+    opts.max_connections(CLI.sqlite_max_connections);
     let pool = SeaOrmDatabase::connect(opts).await?;
     Ok(pool)
 }