func (c *NameLookupCache) CreateImageStore(op trace.Operation, storeName string) (*url.URL, error) {
store, err := util.ImageStoreNameToURL(storeName)
if err != nil {
return nil, err
}
// Check for existence and rehydrate the cache if it exists on disk.
_, err = c.GetImageStore(op, storeName)
// we expect this not to exist.
if err == nil {
return nil, os.ErrExist
}
c.storeCacheLock.Lock()
defer c.storeCacheLock.Unlock()
store, err = c.DataStore.CreateImageStore(op, storeName)
if err != nil {
return nil, err
}
// Create the root image
scratch, err := c.DataStore.WriteImage(op, &Image{Store: store}, Scratch.ID, nil, "", nil)
if err != nil {
return nil, err
}
indx := index.NewIndex()
c.storeCache[*store] = indx
if err = indx.Insert(scratch); err != nil {
return nil, err
}
return store, nil
}
// GetImageStore checks to see if a named image store exists and returls the
// URL to it if so or error.
func (c *NameLookupCache) GetImageStore(op trace.Operation, storeName string) (*url.URL, error) {
store, err := util.ImageStoreNameToURL(storeName)
if err != nil {
return nil, err
}
c.storeCacheLock.Lock()
defer c.storeCacheLock.Unlock()
// check the cache
_, ok := c.storeCache[*store]
if !ok {
infof("Refreshing image cache from datastore.")
// Store isn't in the cache. Look it up in the datastore.
storeName, err := util.ImageStoreName(store)
if err != nil {
return nil, err
}
// If the store doesn't exist, we'll fall out here.
_, err = c.DataStore.GetImageStore(op, storeName)
if err != nil {
return nil, err
}
idx := index.NewIndex()
c.storeCache[*store] = idx
// Add Scratch
scratch, err := c.DataStore.GetImage(op, store, Scratch.ID)
if err != nil {
log.Errorf("ImageCache Error: looking up scratch on %s: %s", store.String(), err)
return nil, ErrCorruptImageStore
}
if err = idx.Insert(scratch); err != nil {
return nil, err
}
// XXX after creating the indx and populating the map, we can put the rest in a go routine
// Fall out here if there are no images. We should at least have a scratch.
images, err := c.DataStore.ListImages(op, store, nil)
if err != nil {
return nil, err
}
debugf("Found %d images", len(images))
// Build image map to simplify tree traversal.
imageMap := make(map[string]*Image, len(images))
for _, img := range images {
if img.ID == Scratch.ID {
continue
}
imageMap[img.Self()] = img
}
for k := range imageMap {
parentTree(k, idx, imageMap)
}
}
return store, nil
}