nmon/internal/groups/service.go

package groups

import (
	"context"
	"time"

	"github.com/v10networks/nmon/internal/clock"
	"github.com/v10networks/nmon/internal/p95"
	"github.com/v10networks/nmon/internal/store"
)

// Inventory is the part of the inventory database this package reads.
// store.Store implements it.
type Inventory interface {
	GetGroup(ctx context.Context, id int64) (*store.GroupRef, error)
	ListGroups(ctx context.Context) ([]store.Group, error)
	GroupMembers(ctx context.Context, groupID int64, from, to time.Time) ([]store.GroupMember, error)
	GetInterface(ctx context.Context, id string) (*store.Interface, error)
}

// Relation maps interface IDs to a related interface ID.
type Relation func(ctx context.Context, ifaceIDs []string) (map[string]string, error)

// Options configures a Service.
type Options struct {
	Query     p95.Querier
	Inventory Inventory
	// Zone is the timezone of group months. A group spans devices and so
	// sites; it uses the site default, not a member's override.
	Zone *time.Location
	// LagParent maps a LAG member interface to its LAG interface. Nothing
	// collects ifStackTable yet, so until discovery supplies this, nil means
	// "no LAG relations known" and no member is ever dropped as a LAG duplicate.
	LagParent Relation
	// LinkPeer maps an interface to the interface at the other end of its
	// link. LLDP neighbours are not in the inventory yet; nil means none known
	// and no group is ever flagged as mixing both ends of a link.
	LinkPeer Relation
	Clock    clock.Clock
}

// Service computes group traffic.
type Service struct {
	o  Options
	rd *p95.Reader
}

// NewService returns a Service.
func NewService(o Options) *Service {
	if o.Clock == nil {
		o.Clock = clock.Real()
	}
	if o.Zone == nil {
		o.Zone = time.UTC
	}
	return &Service{o: o, rd: p95.NewReader(o.Query)}
}