pub trait RuntimePlugin:
Debug
+ Send
+ Sync {
// Provided methods
fn order(&self) -> Order { ... }
fn config(&self) -> Option<FrozenLayer> { ... }
fn runtime_components(
&self,
current_components: &RuntimeComponentsBuilder,
) -> Cow<'_, RuntimeComponentsBuilder> { ... }
}
Expand description
Runtime plugin trait
A RuntimePlugin
is the unit of configuration for augmenting the client with new behavior.
Runtime plugins can register interceptors, set runtime components, and modify configuration.
Provided Methods§
Sourcefn order(&self) -> Order
fn order(&self) -> Order
Runtime plugin ordering.
There are two runtime plugin “levels” that run in the following order:
- Service runtime plugins - runtime plugins that pertain to the entire service.
- Operation runtime plugins - runtime plugins relevant only to a single operation.
This function is used to determine runtime plugin order within those levels. So
regardless of this Order
value, service runtime plugins will still always execute before
operation runtime plugins. However, Defaults
service runtime plugins will run before Overrides
service runtime plugins.
Sourcefn config(&self) -> Option<FrozenLayer>
fn config(&self) -> Option<FrozenLayer>
Optionally returns additional config that should be added to the ConfigBag
.
As a best practice, a frozen layer should be stored on the runtime plugin instance as
a member, and then cloned upon return since that clone is cheap. Constructing a new
Layer
and freezing it will require a lot of allocations.
Sourcefn runtime_components(
&self,
current_components: &RuntimeComponentsBuilder,
) -> Cow<'_, RuntimeComponentsBuilder>
fn runtime_components( &self, current_components: &RuntimeComponentsBuilder, ) -> Cow<'_, RuntimeComponentsBuilder>
Returns a RuntimeComponentsBuilder
to incorporate into the final runtime components.
The order of runtime plugins determines which runtime components “win”. Components set by later runtime plugins will override those set by earlier runtime plugins.
If no runtime component changes are desired, just return an empty builder.
This method returns a Cow
for flexibility. Some implementers may want to store the components builder
as a member and return a reference to it, while others may need to create the builder every call. If possible,
returning a reference is preferred for performance.
Components configured by previous runtime plugins are in the current_components
argument, and can be used
to create nested/wrapped components, such as a connector calling into an inner (customer provided) connector.