memorySbiStore.go

package nucleus

import (
	"encoding/json"

	"code.fbi.h-da.de/danet/gosdn/controller/interfaces/southbound"
	"code.fbi.h-da.de/danet/gosdn/controller/nucleus/errors"
	"code.fbi.h-da.de/danet/gosdn/controller/store"
)

// MemorySbiStore provides a in-memory implementation for sbis.
type MemorySbiStore struct {
	Store           map[string]southbound.LoadedSbi
	nameLookupTable map[string]string
}

// NewMemorySbiStore returns a specific in-memory store for a type T.
func NewMemorySbiStore() southbound.Store {
	return &MemorySbiStore{
		Store:           make(map[string]southbound.LoadedSbi),
		nameLookupTable: make(map[string]string),
	}
}

// Add adds a item to the store.
func (t *MemorySbiStore) Add(item southbound.SouthboundInterface) error {
	var sbi southbound.LoadedSbi

	b, err := json.Marshal(item)
	if err != nil {
		return err
	}
	err = json.Unmarshal(b, &sbi)
	if err != nil {
		return err
	}

	_, ok := t.Store[sbi.ID]
	if ok {
		return nil
	}

	t.Store[sbi.ID] = sbi
	t.nameLookupTable[item.Name()] = sbi.ID

	return nil
}

// Update updates a existing sbi.
func (t *MemorySbiStore) Update(item southbound.SouthboundInterface) error {
	_, ok := t.Store[item.ID().String()]
	if ok {
		return nil
	}

	var sbi southbound.LoadedSbi

	b, err := json.Marshal(item)
	if err != nil {
		return err
	}
	err = json.Unmarshal(b, &sbi)
	if err != nil {
		return err
	}

	t.Store[item.ID().String()] = sbi
	t.nameLookupTable[item.Name()] = item.ID().String()

	return nil
}

// Delete deletes a sbi from the store.
func (t *MemorySbiStore) Delete(item southbound.SouthboundInterface) error {
	delete(t.Store, item.ID().String())

	return nil
}

// Get takes a sbi's UUID or name and returns the sbi.
func (t *MemorySbiStore) Get(query store.Query) (southbound.LoadedSbi, error) {
	// First search for direct hit on UUID.
	item, ok := t.Store[query.ID.String()]
	if !ok {
		// Second search for name
		id, ok := t.nameLookupTable[query.Name]
		if !ok {
			return item, errors.ErrCouldNotFind{ID: query.ID, Name: query.Name}
		}

		item, ok := t.Store[id]
		if !ok {
			return item, errors.ErrCouldNotFind{ID: query.ID, Name: query.Name}
		}

		return item, nil
	}

	return item, nil
}

// GetAll returns all stored sbis.
func (t *MemorySbiStore) GetAll() ([]southbound.LoadedSbi, error) {
	var allItems []southbound.LoadedSbi

	for _, item := range t.Store {
		allItems = append(allItems, item)
	}

	return allItems, nil
}