func (herd *Herd) getImageHaveLock(name string) *image.Image {
if name == "" {
return nil
}
if image := herd.imagesByName[name]; image != nil {
return image
}
connection, err := rpc.DialHTTP("tcp", herd.imageServerAddress)
if err != nil {
herd.logger.Println(err)
return nil
}
defer connection.Close()
var request imageserver.GetImageRequest
request.ImageName = name
var reply imageserver.GetImageResponse
err = connection.Call("ImageServer.GetImage", request, &reply)
if err != nil {
herd.logger.Printf("Error calling\t%s\n", err)
return nil
}
if reply.Image != nil {
if err := reply.Image.FileSystem.RebuildInodePointers(); err != nil {
herd.logger.Printf("Error building inode pointers for image: %s %s",
name, err)
return nil
}
reply.Image.FileSystem.BuildEntryMap()
reply.Image.FileSystem.BuildInodeToFilenamesTable()
reply.Image.FileSystem.BuildHashToInodesTable()
herd.imagesByName[name] = reply.Image
herd.logger.Printf("Got image: %s\n", name)
}
return reply.Image
}
func getImage(client *rpc.Client, name string) (*filesystem.FileSystem, error) {
var request imageserver.GetImageRequest
request.ImageName = name
var reply imageserver.GetImageResponse
if err := client.Call("ImageServer.GetImage", request, &reply); err != nil {
return nil, err
}
if reply.Image == nil {
return nil, errors.New(name + ": not found")
}
reply.Image.FileSystem.RebuildInodePointers()
return reply.Image.FileSystem, nil
}
func (herd *Herd) getImageHaveLock(name string) *image.Image {
if name == "" {
return nil
}
if image := herd.imagesByName[name]; image != nil {
return image
}
// Image not yet known. If it was recently found to be missing, report it
// as missing. This avoids hammering the imageserver with "are we there
// yet?", "are we there yet?", "are we there yet?" queries.
if lastCheck, ok := herd.missingImages[name]; ok {
if time.Since(lastCheck).Seconds() < 1 {
return nil
}
}
imageClient, err := srpc.DialHTTP("tcp", herd.imageServerAddress)
if err != nil {
herd.logger.Println(err)
return nil
}
defer imageClient.Close()
var request imageserver.GetImageRequest
request.ImageName = name
var reply imageserver.GetImageResponse
err = client.CallGetImage(imageClient, request, &reply)
if err != nil {
herd.logger.Printf("Error calling\t%s\n", err)
return nil
}
if reply.Image == nil {
herd.missingImages[name] = time.Now()
} else {
if err := reply.Image.FileSystem.RebuildInodePointers(); err != nil {
herd.logger.Printf("Error building inode pointers for image: %s %s",
name, err)
return nil
}
delete(herd.missingImages, name)
reply.Image.FileSystem.BuildEntryMap()
reply.Image.FileSystem.BuildInodeToFilenamesTable()
reply.Image.FileSystem.BuildHashToInodesTable()
herd.imagesByName[name] = reply.Image
herd.logger.Printf("Got image: %s\n", name)
}
return reply.Image
}