seaweedfs/go/operation/lookup.go
2014-06-02 09:22:23 -07:00

89 lines
2.1 KiB
Go

package operation
import (
"code.google.com/p/weed-fs/go/util"
"encoding/json"
"errors"
_ "fmt"
"math/rand"
"net/url"
"strings"
"time"
)
type Location struct {
Url string `json:"url,omitempty"`
PublicUrl string `json:"publicUrl,omitempty"`
}
type LookupResult struct {
VolumeId string `json:"volumeId,omitempty"`
Locations []Location `json:"locations,omitempty"`
Error string `json:"error,omitempty"`
}
var (
vc VidCache
)
func Lookup(server string, vid string) (ret *LookupResult, err error) {
locations, cache_err := vc.Get(vid)
if cache_err != nil {
if ret, err = do_lookup(server, vid); err == nil {
vc.Set(vid, ret.Locations, 1*time.Minute)
}
} else {
ret = &LookupResult{VolumeId: vid, Locations: locations}
}
return
}
func do_lookup(server string, vid string) (*LookupResult, error) {
values := make(url.Values)
values.Add("volumeId", vid)
jsonBlob, err := util.Post("http://"+server+"/dir/lookup", values)
if err != nil {
return nil, err
}
var ret LookupResult
err = json.Unmarshal(jsonBlob, &ret)
if err != nil {
return nil, err
}
if ret.Error != "" {
return nil, errors.New(ret.Error)
}
return &ret, nil
}
func LookupFileId(server string, fileId string) (fullUrl string, err error) {
parts := strings.Split(fileId, ",")
if len(parts) != 2 {
return "", errors.New("Invalid fileId " + fileId)
}
lookup, lookupError := Lookup(server, parts[0])
if lookupError != nil {
return "", lookupError
}
if len(lookup.Locations) == 0 {
return "", errors.New("File Not Found")
}
return "http://" + lookup.Locations[rand.Intn(len(lookup.Locations))].PublicUrl + "/" + fileId, nil
}
func LookupVolumeIds(server string, vids []string) (map[string]LookupResult, error) {
values := make(url.Values)
for _, vid := range vids {
values.Add("volumeId", vid)
}
jsonBlob, err := util.Post("http://"+server+"/vol/lookup", values)
if err != nil {
return nil, err
}
ret := make(map[string]LookupResult)
err = json.Unmarshal(jsonBlob, &ret)
if err != nil {
return nil, errors.New(err.Error() + " " + string(jsonBlob))
}
return ret, nil
}