Struct Config

pub struct Config {
    pub label_selector: Option<String>,
    pub field_selector: Option<String>,
    pub timeout: Option<u32>,
    pub list_semantic: ListSemantic,
    pub initial_list_strategy: InitialListStrategy,
    pub page_size: Option<u32>,
    pub bookmarks: bool,
}

Accumulates all options that can be used on the watcher invocation.

Fields

label_selector: Option<String>

A selector to restrict the list of returned objects by their labels.

Defaults to everything if None.

field_selector: Option<String>

A selector to restrict the list of returned objects by their fields.

Defaults to everything if None.

timeout: Option<u32>

Timeout for the list/watch call.

This limits the duration of the call, regardless of any activity or inactivity. If unset for a watch call, we will use 290s. We limit this to 295s due to inherent watch limitations.

list_semantic: ListSemantic

Semantics for list calls.

Configures re-list for performance vs. consistency.

NB: This option only has an effect for InitialListStrategy::ListWatch.

initial_list_strategy: InitialListStrategy

Control how the watcher fetches the initial list of objects.

• ListWatch: The watcher will fetch the initial list of objects using a list call.
• StreamingList: The watcher will fetch the initial list of objects using a watch call.

StreamingList is more efficient than ListWatch, but it requires the server to support streaming list bookmarks (opt-in feature gate in Kubernetes 1.27).

See upstream documentation on streaming lists, and the KEP.

page_size: Option<u32>

Maximum number of objects retrieved per list operation resyncs.

This can reduce the memory consumption during resyncs, at the cost of requiring more API roundtrips to complete.

Defaults to 500. Note that None represents unbounded.

NB: This option only has an effect for InitialListStrategy::ListWatch.

bookmarks: bool

Enables watch events with type “BOOKMARK”.

Requests watch bookmarks from the apiserver when enabled for improved watch precision and reduced list calls. This is default enabled and should generally not be turned off.

Implementations

impl Config

Builder interface to Config

Usage:

use kube::runtime::watcher::Config;
let wc = Config::default()
    .timeout(60)
    .labels("kubernetes.io/lifecycle=spot");

pub fn timeout(self, timeout_secs: u32) -> Self

Configure the timeout for list/watch calls

This limits the duration of the call, regardless of any activity or inactivity. Defaults to 290s

pub fn fields(self, field_selector: &str) -> Self

Configure the selector to restrict the list of returned objects by their fields.

Defaults to everything. Supports =, ==, !=, and can be comma separated: key1=value1,key2=value2. The server only supports a limited number of field queries per type.

pub fn labels(self, label_selector: &str) -> Self

Configure the selector to restrict the list of returned objects by their labels.

Defaults to everything. Supports =, ==, !=, and can be comma separated: key1=value1,key2=value2.

pub fn labels_from(self, selector: &Selector) -> Self

Configure typed label selectors

Configure typed selectors from Selector and Expression lists.

use kube_runtime::watcher::Config;
use kube_client::core::{Expression, Selector, ParseExpressionError};
use k8s_openapi::apimachinery::pkg::apis::meta::v1::LabelSelector;
let selector: Selector = Expression::In("env".into(), ["development".into(), "sandbox".into()].into()).into();
let cfg = Config::default().labels_from(&selector);
let cfg = Config::default().labels_from(&Expression::Exists("foo".into()).into());
let selector: Selector = LabelSelector::default().try_into()?;
let cfg = Config::default().labels_from(&selector);

pub fn list_semantic(self, semantic: ListSemantic) -> Self

Sets list semantic to configure re-list performance and consistency

NB: This option only has an effect for InitialListStrategy::ListWatch.

pub fn any_semantic(self) -> Self

Sets list semantic to Any to improve list performance

NB: This option only has an effect for InitialListStrategy::ListWatch.

pub fn disable_bookmarks(self) -> Self

Disables watch bookmarks to simplify watch handling

This is not recommended to use with production watchers as it can cause desyncs. See #219 for details.

pub fn page_size(self, page_size: u32) -> Self

Limits the number of objects retrieved in each list operation during resync.

This can reduce the memory consumption during resyncs, at the cost of requiring more API roundtrips to complete.

NB: This option only has an effect for InitialListStrategy::ListWatch.

pub fn streaming_lists(self) -> Self

Kubernetes 1.27 Streaming Lists Sets list semantic to Stream to make use of watch bookmarks

Trait Implementations

impl Clone for Config

fn clone(&self) -> Config

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Config

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

Formats the value using the given formatter.

impl Default for Config

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for Config

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Config