A ZLayer[E, A, B] describes how to build one or more services in your
application. Services can be injected into effects via ZIO#provide. Effects
can require services via ZIO.service."
Layer can be thought of as recipes for producing bundles of services, given their dependencies (other services).
Construction of services can be effectful and utilize resources that must be acquired and safely released when the services are done being utilized.
By default layers are shared, meaning that if the same layer is used twice the layer will only be allocated a single time.
Because of their excellent composition properties, layers are the idiomatic way in ZIO to create services that depend on other services.
- Companion:
- object
Value members
Concrete methods
Combines this layer with the specified layer, producing a new layer that has the inputs and outputs of = both.
Combines this layer with the specified layer, producing a new layer that has the inputs and outputs of = both.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer, and the outputs of both layers.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer, and the outputs of both layers.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer, and the outputs of both layers.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer, and the outputs of both layers.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer as well as any leftover inputs, and the outputs of the specified layer.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer as well as any leftover inputs, and the outputs of the specified layer.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer as well as any leftover inputs, and the outputs of the specified layer.
Feeds the output services of this layer into the input of the specified layer, resulting in a new layer with the inputs of this layer as well as any leftover inputs, and the outputs of the specified layer.
Provides an effect with part of its required environment, eliminating its dependency on the services output by this layer.
Provides an effect with part of its required environment, eliminating its dependency on the services output by this layer.
Builds a layer into a ZIO value. Any resources associated with this layer will be released when the specified scope is closed unless their scope has been extended. This allows building layers where the lifetime of some of the services output by the layer exceed the lifetime of the effect the layer is provided to.
Builds a layer into a ZIO value. Any resources associated with this layer will be released when the specified scope is closed unless their scope has been extended. This allows building layers where the lifetime of some of the services output by the layer exceed the lifetime of the effect the layer is provided to.
Recovers from all errors.
Recovers from all errors.
Taps the layer, printing the result of calling .toString on the value.
Taps the layer, printing the result of calling .toString on the value.
Taps the layer, printing the result of calling .toString on the value.
Prefixes the output with the given message.
Taps the layer, printing the result of calling .toString on the value.
Prefixes the output with the given message.
Extends the scope of this layer, returning a new layer that when provided to an effect will not immediately release its associated resources when that effect completes execution but instead when the scope the resulting effect depends on is closed.
Extends the scope of this layer, returning a new layer that when provided to an effect will not immediately release its associated resources when that effect completes execution but instead when the scope the resulting effect depends on is closed.
Constructs a layer dynamically based on the output of this layer.
Constructs a layer dynamically based on the output of this layer.
Feeds the error or output services of this layer into the input of either
the specified failure or success layers, resulting in a new layer with
the inputs of this layer, and the error or outputs of the specified layer.
Feeds the error or output services of this layer into the input of either
the specified failure or success layers, resulting in a new layer with
the inputs of this layer, and the error or outputs of the specified layer.
Feeds the error or output services of this layer into the input of either
the specified failure or success layers, resulting in a new layer with
the inputs of this layer, and the error or outputs of the specified layer.
Feeds the error or output services of this layer into the input of either
the specified failure or success layers, resulting in a new layer with
the inputs of this layer, and the error or outputs of the specified layer.
Creates a fresh version of this layer that will not be shared.
Creates a fresh version of this layer that will not be shared.
Builds this layer and uses it until it is interrupted. This is useful when your entire application is a layer, such as an HTTP server.
Builds this layer and uses it until it is interrupted. This is useful when your entire application is a layer, such as an HTTP server.
Returns a new layer whose output is mapped by the specified function.
Returns a new layer whose output is mapped by the specified function.
Returns a layer with its error channel mapped using the specified function.
Returns a layer with its error channel mapped using the specified function.
Returns a layer with its full cause of failure mapped using the specified
function. This can be used to transform errors while preserving the
original structure of Cause.
Returns a layer with its full cause of failure mapped using the specified
function. This can be used to transform errors while preserving the
original structure of Cause.
- See also:
Returns a scoped effect that, if evaluated, will return the lazily computed result of this layer.
Returns a scoped effect that, if evaluated, will return the lazily computed result of this layer.
Translates effect failure into death of the fiber, making all failures unchecked and not a part of the type of the layer.
Translates effect failure into death of the fiber, making all failures unchecked and not a part of the type of the layer.
Executes this layer and returns its output, if it succeeds, but otherwise executes the specified layer.
Executes this layer and returns its output, if it succeeds, but otherwise executes the specified layer.
Returns a new layer that produces the outputs of this layer but also passes through the inputs.
Returns a new layer that produces the outputs of this layer but also passes through the inputs.
Projects out part of one of the services output by this layer using the specified function.
Projects out part of one of the services output by this layer using the specified function.
Returns a layer that produces a reloadable version of this service.
Returns a layer that produces a reloadable version of this service.
Returns a layer that produces a reloadable version of this service, where the reloading schedule is derived from the layer input.
Returns a layer that produces a reloadable version of this service, where the reloading schedule is derived from the layer input.
Returns a layer that produces a reloadable version of this service.
Returns a layer that produces a reloadable version of this service.
Retries constructing this layer according to the specified schedule.
Retries constructing this layer according to the specified schedule.
Performs the specified effect if this layer succeeds.
Performs the specified effect if this layer succeeds.
Performs the specified effect if this layer fails.
Performs the specified effect if this layer fails.
Performs the specified effect if this layer fails.
Performs the specified effect if this layer fails.
Converts a layer that requires no services into a scoped runtime, which can be used to execute effects.
Converts a layer that requires no services into a scoped runtime, which can be used to execute effects.
Replaces the layer's output with Unit.
Replaces the layer's output with Unit.
When used with ZIO.provide and ZLayer.make macros (and their variants), this will suppress the unused layer warning that is normally emitted, and will actually include the layer for its side-effects.
Combines this layer the specified layer, producing a new layer that has the inputs of both, and the outputs of both combined using the specified function.
Combines this layer the specified layer, producing a new layer that has the inputs of both, and the outputs of both combined using the specified function.