Enum QueuePolicy 

pub enum QueuePolicy {
    DropOldest,
    Backpressure,
}

Queue overflow policy for an input.

Variants

DropOldest

Drop the oldest queued message when the queue is full (default).

Backpressure

Buffer up to 10x queue_size without dropping. Drops with ERROR log at hard cap.

Implementations

impl QueuePolicy

pub fn effective_cap(&self, queue_size: usize) -> usize

Returns the effective capacity for a given configured queue size.

• DropOldest: returns queue_size, but never less than 1.
• Backpressure: returns 10 * queue_size (min 100) as a hard safety cap.

A DropOldest cap of 0 would drop 100% of the input’s events — the runtime operator channel sets the just-queued event to None on every add_event, so the operator never receives a single message and the dataflow silently hangs. Clamp queue_size: 0 to 1 (latest-only) instead of turning the input into a dead port.

use dora_message::config::QueuePolicy;

// DropOldest keeps `queue_size`, but never a dead 0-capacity port.
assert_eq!(QueuePolicy::DropOldest.effective_cap(5), 5);
assert_eq!(QueuePolicy::DropOldest.effective_cap(0), 1);

// Backpressure buffers 10x the configured size, with a floor of 100.
assert_eq!(QueuePolicy::Backpressure.effective_cap(5), 100);
assert_eq!(QueuePolicy::Backpressure.effective_cap(50), 500);

Trait Implementations

impl Clone for QueuePolicy

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for QueuePolicy

impl Debug for QueuePolicy

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

Formats the value using the given formatter.

impl Default for QueuePolicy

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for QueuePolicy

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for QueuePolicy

impl JsonSchema for QueuePolicy

fn schema_name() -> Cow<'static, str>

The name of the generated JSON Schema.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

fn json_schema(generator: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn inline_schema() -> bool

Whether JSON Schemas generated for this type should be included directly in parent schemas, rather than being re-used where possible using the $ref keyword.

impl PartialEq for QueuePolicy

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for QueuePolicy

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for QueuePolicy