Golang PrefixEndKey Examples

Example #1

File: zone.go Project: hahan/cockroach

// Get retrieves the zone configuration for the specified key. If the
// key is empty, all zone configurations are returned. Otherwise, the
// leading "/" path delimiter is stripped and the zone configuration
// matching the remainder is retrieved. Note that this will retrieve
// the default zone config if "key" is equal to "/", and will list all
// configs if "key" is equal to "". The body result contains
// JSON-formatted output for a listing of keys and YAML-formatted
// output for retrieval of a zone config.
func (zh *zoneHandler) Get(path string, r *http.Request) (body []byte, contentType string, err error) {
	// Scan all zones if the key is empty.
	if len(path) == 0 {
		sr := <-zh.kvDB.Scan(&storage.ScanRequest{
			RequestHeader: storage.RequestHeader{
				Key:    storage.KeyConfigZonePrefix,
				EndKey: storage.PrefixEndKey(storage.KeyConfigZonePrefix),
				User:   storage.UserRoot,
			},
			MaxResults: maxGetResults,
		})
		if sr.Error != nil {
			err = sr.Error
			return
		}
		if len(sr.Rows) == maxGetResults {
			glog.Warningf("retrieved maximum number of results (%d); some may be missing", maxGetResults)
		}
		var prefixes []string
		for _, kv := range sr.Rows {
			trimmed := bytes.TrimPrefix(kv.Key, storage.KeyConfigZonePrefix)
			prefixes = append(prefixes, url.QueryEscape(string(trimmed)))
		}
		// JSON-encode the prefixes array.
		contentType = "application/json"
		if body, err = json.Marshal(prefixes); err != nil {
			err = util.Errorf("unable to format zone configurations: %v", err)
		}
	} else {
		zoneKey := storage.MakeKey(storage.KeyConfigZonePrefix, storage.Key(path[1:]))
		var ok bool
		config := &storage.ZoneConfig{}
		if ok, _, err = kv.GetI(zh.kvDB, zoneKey, config); err != nil {
			return
		}
		// On get, if there's no zone config for the requested prefix,
		// return a not found error.
		if !ok {
			err = util.Errorf("no config found for key prefix %q", path)
			return
		}
		var out []byte
		if out, err = yaml.Marshal(config); err != nil {
			err = util.Errorf("unable to marshal zone config %+v to yaml: %v", config, err)
			return
		}
		if !utf8.ValidString(string(out)) {
			err = util.Errorf("config contents not valid utf8: %q", out)
			return
		}
		contentType = "text/yaml"
		body = out
	}

	return
}

Example #2

File: zone.go Project: Zemnmez/cockroach

// Get retrieves the zone configuration for the specified key. If the
// key is empty, all zone configurations are returned. Otherwise, the
// leading "/" path delimiter is stripped and the zone configuration
// matching the remainder is retrieved. Note that this will retrieve
// the default zone config if "key" is equal to "/", and will list all
// configs if "key" is equal to "". The body result contains
// JSON-formmatted output via the GetZoneResponse struct.
func (zh *zoneHandler) Get(path string, r *http.Request) (body []byte, contentType string, err error) {
	contentType = "application/json"

	// Scan all zones if the key is empty.
	if len(path) == 0 {
		sr := <-zh.kvDB.Scan(&storage.ScanRequest{
			StartKey:   storage.KeyConfigZonePrefix,
			EndKey:     storage.PrefixEndKey(storage.KeyConfigZonePrefix),
			MaxResults: maxGetResults,
		})
		if sr.Error != nil {
			err = sr.Error
			return
		}
		if len(sr.Rows) == maxGetResults {
			glog.Warningf("retrieved maximum number of results (%d); some may be missing", maxGetResults)
		}
		var prefixes []string
		for _, kv := range sr.Rows {
			trimmed := bytes.TrimPrefix(kv.Key, storage.KeyConfigZonePrefix)
			prefixes = append(prefixes, url.QueryEscape(string(trimmed)))
		}
		// JSON-encode the prefixes array.
		if body, err = json.Marshal(prefixes); err != nil {
			err = util.Errorf("unable to format zone configurations: %v", err)
		}
	} else {
		zoneKey := storage.MakeKey(storage.KeyConfigZonePrefix, storage.Key(path[1:]))
		gr := <-zh.kvDB.Get(&storage.GetRequest{Key: zoneKey})
		if gr.Error != nil {
			return
		}
		// On get, if there's no zone config for the requested prefix,
		// return a not found error.
		if gr.Value.Bytes == nil {
			err = util.Errorf("no config found for key prefix %q", path)
			return
		}
		if !utf8.ValidString(string(gr.Value.Bytes)) {
			err = util.Errorf("config contents not valid utf8: %q", gr.Value)
			return
		}
		body = gr.Value.Bytes
	}

	return
}