Capability on FsFlow

FsFlow.Env

Mon, 01 Jan 0001 00:00:00 +0000

Request token for projecting a value from a dependency.

Remarks

Builders read the dependency from the environment, apply the projection, and then reuse the existing lift/bind behavior for the projected value. If the projection returns a Result, Async, Task, ValueTask, ColdTask, option, or voption, the existing workflow rules still apply.

Examples

type IClock =
     abstract UtcNow : unit -&gt; DateTimeOffset

 type ClockCaps =
     inherit Needs&lt;IClock&gt;
     abstract Clock : IClock

 let readClockNow : Flow&lt;#ClockCaps, unit, DateTimeOffset&gt; =
     flow {
         let! now = Env&lt;IClock&gt; _.UtcNow
         return now
     }

FsFlow.CapabilityModule.environment

Mon, 01 Jan 0001 00:00:00 +0000

Reads the application environment from the environment.

FsFlow.MissingCapability

Mon, 01 Jan 0001 00:00:00 +0000

Describes a missing service-provider capability.

FsFlow.Needs

Mon, 01 Jan 0001 00:00:00 +0000

Describes the capability contract for a single dependency.

Remarks

Named cap-set interfaces inherit this contract once and then expose the dependency through a member such as Clock or Logger. Workflow builders can accept any environment that implements Needs<'dep>, which lets larger runtimes satisfy smaller boundaries.

Examples

type IClock =
     abstract UtcNow : unit -&gt; DateTimeOffset

 type ClockCaps =
     inherit Needs&lt;IClock&gt;
     abstract Clock : IClock

FsFlow.LayerModule.provideLayer

Mon, 01 Jan 0001 00:00:00 +0000

Provides a derived environment from a layer flow to a downstream flow.

FsFlow.CapabilityModule.runtime

Mon, 01 Jan 0001 00:00:00 +0000

Reads the current runtime from the environment.

FsFlow.CapabilityModule.service

Mon, 01 Jan 0001 00:00:00 +0000

Reads a service from the environment using the provided projection.

FsFlow.CapabilityModule.serviceFromProvider

Mon, 01 Jan 0001 00:00:00 +0000

Reads a service from IServiceProvider and fails when it is not registered.