package registry import ( "encoding/json" "errors" "fmt" "io/ioutil" "net/http" "net/url" "strings" "github.com/docker/docker/pkg/log" ) // scans string for api version in the URL path. returns the trimmed hostname, if version found, string and API version. func scanForApiVersion(hostname string) (string, APIVersion) { var ( chunks []string apiVersionStr string ) if strings.HasSuffix(hostname, "/") { chunks = strings.Split(hostname[:len(hostname)-1], "/") apiVersionStr = chunks[len(chunks)-1] } else { chunks = strings.Split(hostname, "/") apiVersionStr = chunks[len(chunks)-1] } for k, v := range apiVersions { if apiVersionStr == v { hostname = strings.Join(chunks[:len(chunks)-1], "/") return hostname, k } } return hostname, DefaultAPIVersion } func NewEndpoint(hostname string) (*Endpoint, error) { var ( endpoint Endpoint trimmedHostname string err error ) if !strings.HasPrefix(hostname, "http") { hostname = "https://" + hostname } trimmedHostname, endpoint.Version = scanForApiVersion(hostname) endpoint.URL, err = url.Parse(trimmedHostname) if err != nil { return nil, err } endpoint.URL.Scheme = "https" if _, err := endpoint.Ping(); err != nil { log.Debugf("Registry %s does not work (%s), falling back to http", endpoint, err) // TODO: Check if http fallback is enabled endpoint.URL.Scheme = "http" if _, err = endpoint.Ping(); err != nil { return nil, errors.New("Invalid Registry endpoint: " + err.Error()) } } return &endpoint, nil } type Endpoint struct { URL *url.URL Version APIVersion } // Get the formated URL for the root of this registry Endpoint func (e Endpoint) String() string { return fmt.Sprintf("%s/v%d/", e.URL.String(), e.Version) } func (e Endpoint) VersionString(version APIVersion) string { return fmt.Sprintf("%s/v%d/", e.URL.String(), version) } func (e Endpoint) Ping() (RegistryInfo, error) { if e.String() == IndexServerAddress() { // Skip the check, we now this one is valid // (and we never want to fallback to http in case of error) return RegistryInfo{Standalone: false}, nil } req, err := http.NewRequest("GET", e.String()+"_ping", nil) if err != nil { return RegistryInfo{Standalone: false}, err } resp, _, err := doRequest(req, nil, ConnectTimeout) if err != nil { return RegistryInfo{Standalone: false}, err } defer resp.Body.Close() jsonString, err := ioutil.ReadAll(resp.Body) if err != nil { return RegistryInfo{Standalone: false}, fmt.Errorf("Error while reading the http response: %s", err) } // If the header is absent, we assume true for compatibility with earlier // versions of the registry. default to true info := RegistryInfo{ Standalone: true, } if err := json.Unmarshal(jsonString, &info); err != nil { log.Debugf("Error unmarshalling the _ping RegistryInfo: %s", err) // don't stop here. Just assume sane defaults } if hdr := resp.Header.Get("X-Docker-Registry-Version"); hdr != "" { log.Debugf("Registry version header: '%s'", hdr) info.Version = hdr } log.Debugf("RegistryInfo.Version: %q", info.Version) standalone := resp.Header.Get("X-Docker-Registry-Standalone") log.Debugf("Registry standalone header: '%s'", standalone) // Accepted values are "true" (case-insensitive) and "1". if strings.EqualFold(standalone, "true") || standalone == "1" { info.Standalone = true } else if len(standalone) > 0 { // there is a header set, and it is not "true" or "1", so assume fails info.Standalone = false } log.Debugf("RegistryInfo.Standalone: %t", info.Standalone) return info, nil }