github.com/juju/juju@v0.0.0-20240327075706-a90865de2538/worker/caasrbacmapper/manifold.go (about)

     1  // Copyright 2020 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  package caasrbacmapper
     5  
     6  import (
     7  	"github.com/juju/errors"
     8  	"github.com/juju/worker/v3"
     9  	"github.com/juju/worker/v3/dependency"
    10  	"k8s.io/client-go/informers"
    11  )
    12  
    13  type K8sBroker interface {
    14  	SharedInformerFactory() informers.SharedInformerFactory
    15  }
    16  
    17  type Logger interface {
    18  	Errorf(string, ...interface{})
    19  }
    20  
    21  type ManifoldConfig struct {
    22  	BrokerName string
    23  	Logger     Logger
    24  }
    25  
    26  func Manifold(config ManifoldConfig) dependency.Manifold {
    27  	return dependency.Manifold{
    28  		Inputs: []string{
    29  			config.BrokerName,
    30  		},
    31  		Output: manifoldOutput,
    32  		Start:  config.Start,
    33  	}
    34  }
    35  
    36  func manifoldOutput(in worker.Worker, out interface{}) error {
    37  	inMapper, ok := in.(Mapper)
    38  	if !ok {
    39  		return errors.Errorf("expected Mapper, got %T", in)
    40  	}
    41  
    42  	switch result := out.(type) {
    43  	case *Mapper:
    44  		*result = inMapper
    45  	default:
    46  		return errors.Errorf("expected Mapper, got %T", out)
    47  	}
    48  	return nil
    49  }
    50  
    51  func (c ManifoldConfig) Start(context dependency.Context) (worker.Worker, error) {
    52  	if err := c.Validate(); err != nil {
    53  		return nil, errors.Trace(err)
    54  	}
    55  
    56  	var broker K8sBroker
    57  	if err := context.Get(c.BrokerName, &broker); err != nil {
    58  		return nil, errors.Trace(err)
    59  	}
    60  
    61  	return NewMapper(c.Logger, broker.SharedInformerFactory().Core().V1().ServiceAccounts())
    62  }
    63  
    64  func (c ManifoldConfig) Validate() error {
    65  	if c.BrokerName == "" {
    66  		return errors.NotValidf("empty BrokerName")
    67  	}
    68  	if c.Logger == nil {
    69  		return errors.NotValidf("nil Logger")
    70  	}
    71  	return nil
    72  }