github.com/juju/juju@v0.0.0-20240430160146-1752b71fcf00/worker/fanconfigurer/manifold.go (about)

     1  // Copyright 2017 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  package fanconfigurer
     5  
     6  import (
     7  	"github.com/juju/clock"
     8  	"github.com/juju/errors"
     9  	"github.com/juju/worker/v3"
    10  	"github.com/juju/worker/v3/dependency"
    11  
    12  	apifanconfigurer "github.com/juju/juju/api/agent/fanconfigurer"
    13  	"github.com/juju/juju/api/base"
    14  )
    15  
    16  // ManifoldConfig defines the names of the manifolds on which a
    17  // Manifold will depend.
    18  type ManifoldConfig struct {
    19  	// These are the dependency resource names.
    20  	APICallerName string
    21  	Clock         clock.Clock
    22  }
    23  
    24  // Manifold returns a dependency manifold that runs a fan configurer
    25  // worker, using the resource names defined in the supplied config.
    26  func Manifold(config ManifoldConfig) dependency.Manifold {
    27  	return dependency.Manifold{
    28  		Inputs: []string{
    29  			config.APICallerName,
    30  		},
    31  		Output: func(in worker.Worker, out interface{}) error {
    32  			inWorker, _ := in.(*FanConfigurer)
    33  			if inWorker == nil {
    34  				return errors.Errorf("in should be a %T; got %T", inWorker, in)
    35  			}
    36  			switch outPointer := out.(type) {
    37  			case *bool:
    38  				*outPointer = true
    39  			default:
    40  				return errors.Errorf("out should be *bool; got %T", out)
    41  			}
    42  			return nil
    43  		},
    44  		Start: func(context dependency.Context) (worker.Worker, error) {
    45  			var apiCaller base.APICaller
    46  			if err := context.Get(config.APICallerName, &apiCaller); err != nil {
    47  				return nil, errors.Trace(err)
    48  			}
    49  
    50  			facade := apifanconfigurer.NewFacade(apiCaller)
    51  
    52  			fanconfigurer, err := NewFanConfigurer(FanConfigurerConfig{
    53  				Facade: facade,
    54  			}, config.Clock)
    55  			return fanconfigurer, errors.Annotate(err, "creating fanconfigurer orchestrator")
    56  		},
    57  	}
    58  }