github.com/m3db/m3@v1.5.0/src/cluster/services/leader/options.go (about)

     1  // Copyright (c) 2017 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package leader
    22  
    23  import (
    24  	"errors"
    25  
    26  	"github.com/m3db/m3/src/cluster/services"
    27  )
    28  
    29  var (
    30  	errMissingSid   = errors.New("leader options must specify service ID")
    31  	errMissingEOpts = errors.New("leader options election opts cannot be nil")
    32  )
    33  
    34  // Options describe options for creating a leader service.
    35  type Options interface {
    36  	// Service the election is campaigning for.
    37  	ServiceID() services.ServiceID
    38  	SetServiceID(sid services.ServiceID) Options
    39  
    40  	ElectionOpts() services.ElectionOptions
    41  	SetElectionOpts(e services.ElectionOptions) Options
    42  
    43  	Validate() error
    44  }
    45  
    46  // NewOptions returns an instance of leader options.
    47  func NewOptions() Options {
    48  	return options{
    49  		eo: services.NewElectionOptions(),
    50  	}
    51  }
    52  
    53  type options struct {
    54  	sid services.ServiceID
    55  	eo  services.ElectionOptions
    56  }
    57  
    58  func (o options) ServiceID() services.ServiceID {
    59  	return o.sid
    60  }
    61  
    62  func (o options) SetServiceID(sid services.ServiceID) Options {
    63  	o.sid = sid
    64  	return o
    65  }
    66  
    67  func (o options) ElectionOpts() services.ElectionOptions {
    68  	return o.eo
    69  }
    70  
    71  func (o options) SetElectionOpts(eo services.ElectionOptions) Options {
    72  	o.eo = eo
    73  	return o
    74  }
    75  
    76  func (o options) Validate() error {
    77  	if o.sid == nil {
    78  		return errMissingSid
    79  	}
    80  
    81  	// This shouldn't happen since we have sane defaults but prevents user error.
    82  	if o.eo == nil {
    83  		return errMissingEOpts
    84  	}
    85  
    86  	return nil
    87  }