X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/f553dd496de6b30bf7263424c17e4be4452b593e..3ede205bf0e5af7a88e04009cd66ff111e0729c3:/sdk/go/arvadosclient/arvadosclient.go diff --git a/sdk/go/arvadosclient/arvadosclient.go b/sdk/go/arvadosclient/arvadosclient.go index fae26c1019..8cdfa484bd 100644 --- a/sdk/go/arvadosclient/arvadosclient.go +++ b/sdk/go/arvadosclient/arvadosclient.go @@ -14,6 +14,7 @@ import ( "os" "regexp" "strings" + "time" ) type StringMatcher func(string) bool @@ -25,6 +26,14 @@ var MissingArvadosApiHost = errors.New("Missing required environment variable AR var MissingArvadosApiToken = errors.New("Missing required environment variable ARVADOS_API_TOKEN") var ErrInvalidArgument = errors.New("Invalid argument") +// A common failure mode is to reuse a keepalive connection that has been +// terminated (in a way that we can't detect) for being idle too long. +// POST and DELETE are not safe to retry automatically, so we minimize +// such failures by always using a new or recently active socket. +var MaxIdleConnectionDuration = 30 * time.Second + +var RetryDelay = 2 * time.Second + // Indicates an error that was returned by the API server. type APIServerError struct { // Address of server returning error, of the form "host:port". @@ -58,6 +67,9 @@ type Dict map[string]interface{} // Information about how to contact the Arvados server type ArvadosClient struct { + // https + Scheme string + // Arvados API server, form "host:port" ApiServer string @@ -76,18 +88,11 @@ type ArvadosClient struct { // Discovery document DiscoveryDoc Dict -} -// APIConfig struct consists of: -// APIToken string -// APIHost string -// APIHostInsecure bool -// ExternalClient bool -type APIConfig struct { - APIToken string - APIHost string - APIHostInsecure bool - ExternalClient bool + lastClosedIdlesAt time.Time + + // Number of retries + Retries int } // Create a new ArvadosClient, initialized with standard Arvados environment @@ -99,12 +104,14 @@ func MakeArvadosClient() (ac ArvadosClient, err error) { external := matchTrue.MatchString(os.Getenv("ARVADOS_EXTERNAL_CLIENT")) ac = ArvadosClient{ + Scheme: "https", ApiServer: os.Getenv("ARVADOS_API_HOST"), ApiToken: os.Getenv("ARVADOS_API_TOKEN"), ApiInsecure: insecure, Client: &http.Client{Transport: &http.Transport{ TLSClientConfig: &tls.Config{InsecureSkipVerify: insecure}}}, - External: external} + External: external, + Retries: 2} if ac.ApiServer == "" { return ac, MissingArvadosApiHost @@ -113,16 +120,20 @@ func MakeArvadosClient() (ac ArvadosClient, err error) { return ac, MissingArvadosApiToken } + ac.lastClosedIdlesAt = time.Now() + return ac, err } // CallRaw is the same as Call() but returns a Reader that reads the // response body, instead of taking an output object. func (c ArvadosClient) CallRaw(method string, resourceType string, uuid string, action string, parameters Dict) (reader io.ReadCloser, err error) { - var req *http.Request - + scheme := c.Scheme + if scheme == "" { + scheme = "https" + } u := url.URL{ - Scheme: "https", + Scheme: scheme, Host: c.ApiServer} if resourceType != API_DISCOVERY_RESOURCE { @@ -152,36 +163,73 @@ func (c ArvadosClient) CallRaw(method string, resourceType string, uuid string, } } - if method == "GET" || method == "HEAD" { - u.RawQuery = vals.Encode() - if req, err = http.NewRequest(method, u.String(), nil); err != nil { - return nil, err - } - } else { - if req, err = http.NewRequest(method, u.String(), bytes.NewBufferString(vals.Encode())); err != nil { - return nil, err - } - req.Header.Add("Content-Type", "application/x-www-form-urlencoded") + retryable := false + switch method { + case "GET", "HEAD", "PUT", "OPTIONS", "DELETE": + retryable = true } - // Add api token header - req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", c.ApiToken)) - if c.External { - req.Header.Add("X-External-Client", "1") + // Non-retryable methods such as POST are not safe to retry automatically, + // so we minimize such failures by always using a new or recently active socket + if !retryable { + if time.Since(c.lastClosedIdlesAt) > MaxIdleConnectionDuration { + c.lastClosedIdlesAt = time.Now() + c.Client.Transport.(*http.Transport).CloseIdleConnections() + } } // Make the request + var req *http.Request var resp *http.Response - if resp, err = c.Client.Do(req); err != nil { - return nil, err - } - if resp.StatusCode == http.StatusOK { - return resp.Body, nil + for attempt := 0; attempt <= c.Retries; attempt++ { + if method == "GET" || method == "HEAD" { + u.RawQuery = vals.Encode() + if req, err = http.NewRequest(method, u.String(), nil); err != nil { + return nil, err + } + } else { + if req, err = http.NewRequest(method, u.String(), bytes.NewBufferString(vals.Encode())); err != nil { + return nil, err + } + req.Header.Add("Content-Type", "application/x-www-form-urlencoded") + } + + // Add api token header + req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", c.ApiToken)) + if c.External { + req.Header.Add("X-External-Client", "1") + } + + resp, err = c.Client.Do(req) + if err != nil { + if retryable { + time.Sleep(RetryDelay) + continue + } else { + return nil, err + } + } + + if resp.StatusCode == http.StatusOK { + return resp.Body, nil + } + + defer resp.Body.Close() + + switch resp.StatusCode { + case 408, 409, 422, 423, 500, 502, 503, 504: + time.Sleep(RetryDelay) + continue + default: + return nil, newAPIServerError(c.ApiServer, resp) + } } - defer resp.Body.Close() - return nil, newAPIServerError(c.ApiServer, resp) + if resp != nil { + return nil, newAPIServerError(c.ApiServer, resp) + } + return nil, err } func newAPIServerError(ServerAddress string, resp *http.Response) APIServerError { @@ -225,7 +273,7 @@ func newAPIServerError(ServerAddress string, resp *http.Response) APIServerError // Returns a non-nil error if an error occurs making the API call, the // API responds with a non-successful HTTP status, or an error occurs // parsing the response body. -func (c ArvadosClient) Call(method string, resourceType string, uuid string, action string, parameters Dict, output interface{}) error { +func (c ArvadosClient) Call(method, resourceType, uuid, action string, parameters Dict, output interface{}) error { reader, err := c.CallRaw(method, resourceType, uuid, action, parameters) if reader != nil { defer reader.Close()