Struct FallbackConfig 

pub struct FallbackConfig {
    pub enabled: bool,
    pub on_status: Vec<u16>,
    pub on_rate_limit: bool,
    pub with_replacement: bool,
    pub max_attempts: Option<usize>,
    pub backoff: Option<BackoffConfig>,
    pub max_total_backoff_ms: Option<u64>,
}

Configuration for fallback behavior when requests fail

Fields

enabled: bool

Whether fallback is enabled

on_status: Vec<u16>

Status codes that trigger fallback to the next provider. Supports wildcards: 50 matches all 50x codes (500-509), 5 matches all 5xx codes (500-599). Common values: [429, 502, 503, 504] or [5] for all 5xx errors.

on_rate_limit: bool

Whether to fallback on local rate limits (pool-level and provider-level). If true, hitting a local rate limit will try the next provider instead of returning 429.

with_replacement: bool

When true, weighted random failover samples with replacement, allowing the same provider to be retried. Only affects WeightedRandom strategy.

max_attempts: Option<usize>

Maximum number of failover attempts. Defaults to provider count. This is an attempt budget above the LB strategy: values larger than the provider count retry across additional passes through the pool (the cascade restarts), so it is useful for every strategy — including a single-provider Priority pool — not only with with_replacement: true.

backoff: Option<BackoffConfig>

Inter-attempt backoff. When unset (default), attempts proceed with no delay.

max_total_backoff_ms: Option<u64>

Cap on cumulative time spent sleeping between attempts, in milliseconds. When the next scheduled backoff would push the total past this cap, the retry loop terminates and the last error is returned to the client. Bounds only the inter-attempt sleeps, not upstream request time.

Implementations

impl FallbackConfig

pub fn should_fallback_on_status(&self, status: u16) -> bool

Check if a status code should trigger fallback

Trait Implementations

impl Clone for FallbackConfig

fn clone(&self) -> FallbackConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FallbackConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FallbackConfig

fn default() -> FallbackConfig

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for FallbackConfig

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for FallbackConfig

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.