Struct RateLimitPlugin 

pub struct RateLimitPlugin {
    requests_per_second: u64,
    burst: u64,
    key_source: KeySource,
    buckets: Arc<DashMap<String, TokenBucket>>,
}

Enforces a per-client request rate using the token bucket algorithm.

Each client key gets its own bucket sized burst and refilled at requests_per_second; the key is the remote address by default or the value of a configured header (falling back to the remote address when the header is absent). Over-limit requests are rejected with a 429 JSON response and a Retry-After: 1 header, exiting through the limited port. Does not write to context.message.

Fields

requests_per_second: u64

Sustained refill rate: tokens added per second.

burst: u64

Bucket capacity: maximum requests allowed in a burst.

key_source: KeySource

Where the per-client key is taken from.

buckets: Arc<DashMap<String, TokenBucket>>

Per-key token buckets, created lazily on first request.

Implementations

impl RateLimitPlugin

pub fn from_config(config: &HashMap<String, Value>) -> Result<Self, String>

Builds the plugin from node config. Never fails; every key has a default.

Accepted keys:

• requests_per_second (integer, default 100): sustained rate per client key.
• burst (integer, default = requests_per_second): bucket capacity.
• key_from (string, default remote address): use "header:<name>" to key on a request header instead; any other value keys on the remote address.

type: rate-limit
config:
  requests_per_second: 10
  burst: 20
  key_from: "header:x-api-key"

Trait Implementations

impl Plugin for RateLimitPlugin

fn plugin_type(&self) -> &str

Unique identifier for the plugin type (e.g., “proxy-rewrite”, “upstream”). This is also the key its PortSpec is registered under in port_spec.

fn execute<'life0, 'async_trait>( &'life0 self, ctx: Context, ) -> Pin<Box<dyn Future<Output = Result<PluginOutput, PluginExecutionError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Executes the plugin logic against the request/response context.

fn reads_response_body(&self) -> bool

Whether this configured instance reads context.response.body.

fn cache_target(&self) -> Option<CacheTarget>

The cache backend this node writes to, if it is a proxy-cache half.