vendor/github.com/go-kit/kit/examples/shipping/cargo/cargo.go

   1 // Package cargo contains the heart of the domain model.
   2 package cargo
   3
   4 import (
   5         "errors"
   6         "strings"
   7         "time"
   8
   9         "github.com/pborman/uuid"
  10
  11         "github.com/go-kit/kit/examples/shipping/location"
  12 )
  13
  14 // TrackingID uniquely identifies a particular cargo.
  15 type TrackingID string
  16
  17 // Cargo is the central class in the domain model.
  18 type Cargo struct {
  19         TrackingID         TrackingID
  20         Origin             location.UNLocode
  21         RouteSpecification RouteSpecification
  22         Itinerary          Itinerary
  23         Delivery           Delivery
  24 }
  25
  26 // SpecifyNewRoute specifies a new route for this cargo.
  27 func (c *Cargo) SpecifyNewRoute(rs RouteSpecification) {
  28         c.RouteSpecification = rs
  29         c.Delivery = c.Delivery.UpdateOnRouting(c.RouteSpecification, c.Itinerary)
  30 }
  31
  32 // AssignToRoute attaches a new itinerary to this cargo.
  33 func (c *Cargo) AssignToRoute(itinerary Itinerary) {
  34         c.Itinerary = itinerary
  35         c.Delivery = c.Delivery.UpdateOnRouting(c.RouteSpecification, c.Itinerary)
  36 }
  37
  38 // DeriveDeliveryProgress updates all aspects of the cargo aggregate status
  39 // based on the current route specification, itinerary and handling of the cargo.
  40 func (c *Cargo) DeriveDeliveryProgress(history HandlingHistory) {
  41         c.Delivery = DeriveDeliveryFrom(c.RouteSpecification, c.Itinerary, history)
  42 }
  43
  44 // New creates a new, unrouted cargo.
  45 func New(id TrackingID, rs RouteSpecification) *Cargo {
  46         itinerary := Itinerary{}
  47         history := HandlingHistory{make([]HandlingEvent, 0)}
  48
  49         return &Cargo{
  50                 TrackingID:         id,
  51                 Origin:             rs.Origin,
  52                 RouteSpecification: rs,
  53                 Delivery:           DeriveDeliveryFrom(rs, itinerary, history),
  54         }
  55 }
  56
  57 // Repository provides access a cargo store.
  58 type Repository interface {
  59         Store(cargo *Cargo) error
  60         Find(id TrackingID) (*Cargo, error)
  61         FindAll() []*Cargo
  62 }
  63
  64 // ErrUnknown is used when a cargo could not be found.
  65 var ErrUnknown = errors.New("unknown cargo")
  66
  67 // NextTrackingID generates a new tracking ID.
  68 // TODO: Move to infrastructure(?)
  69 func NextTrackingID() TrackingID {
  70         return TrackingID(strings.Split(strings.ToUpper(uuid.New()), "-")[0])
  71 }
  72
  73 // RouteSpecification Contains information about a route: its origin,
  74 // destination and arrival deadline.
  75 type RouteSpecification struct {
  76         Origin          location.UNLocode
  77         Destination     location.UNLocode
  78         ArrivalDeadline time.Time
  79 }
  80
  81 // IsSatisfiedBy checks whether provided itinerary satisfies this
  82 // specification.
  83 func (s RouteSpecification) IsSatisfiedBy(itinerary Itinerary) bool {
  84         return itinerary.Legs != nil &&
  85                 s.Origin == itinerary.InitialDepartureLocation() &&
  86                 s.Destination == itinerary.FinalArrivalLocation()
  87 }
  88
  89 // RoutingStatus describes status of cargo routing.
  90 type RoutingStatus int
  91
  92 // Valid routing statuses.
  93 const (
  94         NotRouted RoutingStatus = iota
  95         Misrouted
  96         Routed
  97 )
  98
  99 func (s RoutingStatus) String() string {
 100         switch s {
 101         case NotRouted:
 102                 return "Not routed"
 103         case Misrouted:
 104                 return "Misrouted"
 105         case Routed:
 106                 return "Routed"
 107         }
 108         return ""
 109 }
 110
 111 // TransportStatus describes status of cargo transportation.
 112 type TransportStatus int
 113
 114 // Valid transport statuses.
 115 const (
 116         NotReceived TransportStatus = iota
 117         InPort
 118         OnboardCarrier
 119         Claimed
 120         Unknown
 121 )
 122
 123 func (s TransportStatus) String() string {
 124         switch s {
 125         case NotReceived:
 126                 return "Not received"
 127         case InPort:
 128                 return "In port"
 129         case OnboardCarrier:
 130                 return "Onboard carrier"
 131         case Claimed:
 132                 return "Claimed"
 133         case Unknown:
 134                 return "Unknown"
 135         }
 136         return ""
 137 }