Struct RdsIamTokenProvider 

pub struct RdsIamTokenProvider {
    pub(crate) parsed: ParsedDbUrl,
    pub(crate) cached_url: Arc<ArcSwap<String>>,
    generator: Box<dyn TokenGenerator>,
}

Generates RDS IAM auth tokens and caches a ready-to-use database URL.

The cached URL is atomically swapped via ArcSwap so both sync (r2d2) and async (deadpool) pools can read it lock-free. A background tokio task refreshes the token well before the 15-minute AWS expiry.

Fields

parsed: ParsedDbUrl

cached_url: Arc<ArcSwap<String>>

generator: Box<dyn TokenGenerator>

Implementations

impl RdsIamTokenProvider

pub async fn new(database_url: &str) -> Result<Arc<Self>>

Initialize the provider: load AWS credentials, generate the first token, and return a ready provider. Call Self::spawn_refresh_task after to keep the token fresh.

pub(crate) fn with_generator( parsed: ParsedDbUrl, generator: Box<dyn TokenGenerator>, ) -> Arc<Self>

Create a provider with a custom token generator. Used for testing without AWS credentials. Does NOT call refresh() — caller must seed the URL via Self::store_url or call Self::refresh.

pub fn current_url(&self) -> Arc<String>

Return the current database URL with a valid IAM token as password.

pub fn store_url(&self, url: String)

Atomically store a new URL (used by refresh and tests).

pub async fn refresh(&self) -> Result<()>

Generate a fresh auth token and update the cached URL.

pub fn spawn_refresh_task(self: &Arc<Self>) -> JoinHandle<()>

Spawn a background task that refreshes the token every 10 minutes. On failure, retries with exponential backoff (30s, 60s, 120s) before falling back to the normal 10-minute cadence.