diff options
Diffstat (limited to 'vendor/github.com/Azure/go-autorest/autorest/azure/async.go')
-rw-r--r-- | vendor/github.com/Azure/go-autorest/autorest/azure/async.go | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/vendor/github.com/Azure/go-autorest/autorest/azure/async.go b/vendor/github.com/Azure/go-autorest/autorest/azure/async.go new file mode 100644 index 000000000..6e076981f --- /dev/null +++ b/vendor/github.com/Azure/go-autorest/autorest/azure/async.go @@ -0,0 +1,308 @@ +package azure + +import ( + "bytes" + "fmt" + "io/ioutil" + "net/http" + "strings" + "time" + + "github.com/Azure/go-autorest/autorest" + "github.com/Azure/go-autorest/autorest/date" +) + +const ( + headerAsyncOperation = "Azure-AsyncOperation" +) + +const ( + methodDelete = "DELETE" + methodPatch = "PATCH" + methodPost = "POST" + methodPut = "PUT" + methodGet = "GET" + + operationInProgress string = "InProgress" + operationCanceled string = "Canceled" + operationFailed string = "Failed" + operationSucceeded string = "Succeeded" +) + +// DoPollForAsynchronous returns a SendDecorator that polls if the http.Response is for an Azure +// long-running operation. It will delay between requests for the duration specified in the +// RetryAfter header or, if the header is absent, the passed delay. Polling may be canceled by +// closing the optional channel on the http.Request. +func DoPollForAsynchronous(delay time.Duration) autorest.SendDecorator { + return func(s autorest.Sender) autorest.Sender { + return autorest.SenderFunc(func(r *http.Request) (resp *http.Response, err error) { + resp, err = s.Do(r) + if err != nil { + return resp, err + } + pollingCodes := []int{http.StatusAccepted, http.StatusCreated, http.StatusOK} + if !autorest.ResponseHasStatusCode(resp, pollingCodes...) { + return resp, nil + } + + ps := pollingState{} + for err == nil { + err = updatePollingState(resp, &ps) + if err != nil { + break + } + if ps.hasTerminated() { + if !ps.hasSucceeded() { + err = ps + } + break + } + + r, err = newPollingRequest(resp, ps) + if err != nil { + return resp, err + } + + delay = autorest.GetRetryAfter(resp, delay) + resp, err = autorest.SendWithSender(s, r, + autorest.AfterDelay(delay)) + } + + return resp, err + }) + } +} + +func getAsyncOperation(resp *http.Response) string { + return resp.Header.Get(http.CanonicalHeaderKey(headerAsyncOperation)) +} + +func hasSucceeded(state string) bool { + return state == operationSucceeded +} + +func hasTerminated(state string) bool { + switch state { + case operationCanceled, operationFailed, operationSucceeded: + return true + default: + return false + } +} + +func hasFailed(state string) bool { + return state == operationFailed +} + +type provisioningTracker interface { + state() string + hasSucceeded() bool + hasTerminated() bool +} + +type operationResource struct { + // Note: + // The specification states services should return the "id" field. However some return it as + // "operationId". + ID string `json:"id"` + OperationID string `json:"operationId"` + Name string `json:"name"` + Status string `json:"status"` + Properties map[string]interface{} `json:"properties"` + OperationError ServiceError `json:"error"` + StartTime date.Time `json:"startTime"` + EndTime date.Time `json:"endTime"` + PercentComplete float64 `json:"percentComplete"` +} + +func (or operationResource) state() string { + return or.Status +} + +func (or operationResource) hasSucceeded() bool { + return hasSucceeded(or.state()) +} + +func (or operationResource) hasTerminated() bool { + return hasTerminated(or.state()) +} + +type provisioningProperties struct { + ProvisioningState string `json:"provisioningState"` +} + +type provisioningStatus struct { + Properties provisioningProperties `json:"properties,omitempty"` + ProvisioningError ServiceError `json:"error,omitempty"` +} + +func (ps provisioningStatus) state() string { + return ps.Properties.ProvisioningState +} + +func (ps provisioningStatus) hasSucceeded() bool { + return hasSucceeded(ps.state()) +} + +func (ps provisioningStatus) hasTerminated() bool { + return hasTerminated(ps.state()) +} + +func (ps provisioningStatus) hasProvisioningError() bool { + return ps.ProvisioningError != ServiceError{} +} + +type pollingResponseFormat string + +const ( + usesOperationResponse pollingResponseFormat = "OperationResponse" + usesProvisioningStatus pollingResponseFormat = "ProvisioningStatus" + formatIsUnknown pollingResponseFormat = "" +) + +type pollingState struct { + responseFormat pollingResponseFormat + uri string + state string + code string + message string +} + +func (ps pollingState) hasSucceeded() bool { + return hasSucceeded(ps.state) +} + +func (ps pollingState) hasTerminated() bool { + return hasTerminated(ps.state) +} + +func (ps pollingState) hasFailed() bool { + return hasFailed(ps.state) +} + +func (ps pollingState) Error() string { + return fmt.Sprintf("Long running operation terminated with status '%s': Code=%q Message=%q", ps.state, ps.code, ps.message) +} + +// updatePollingState maps the operation status -- retrieved from either a provisioningState +// field, the status field of an OperationResource, or inferred from the HTTP status code -- +// into a well-known states. Since the process begins from the initial request, the state +// always comes from either a the provisioningState returned or is inferred from the HTTP +// status code. Subsequent requests will read an Azure OperationResource object if the +// service initially returned the Azure-AsyncOperation header. The responseFormat field notes +// the expected response format. +func updatePollingState(resp *http.Response, ps *pollingState) error { + // Determine the response shape + // -- The first response will always be a provisioningStatus response; only the polling requests, + // depending on the header returned, may be something otherwise. + var pt provisioningTracker + if ps.responseFormat == usesOperationResponse { + pt = &operationResource{} + } else { + pt = &provisioningStatus{} + } + + // If this is the first request (that is, the polling response shape is unknown), determine how + // to poll and what to expect + if ps.responseFormat == formatIsUnknown { + req := resp.Request + if req == nil { + return autorest.NewError("azure", "updatePollingState", "Azure Polling Error - Original HTTP request is missing") + } + + // Prefer the Azure-AsyncOperation header + ps.uri = getAsyncOperation(resp) + if ps.uri != "" { + ps.responseFormat = usesOperationResponse + } else { + ps.responseFormat = usesProvisioningStatus + } + + // Else, use the Location header + if ps.uri == "" { + ps.uri = autorest.GetLocation(resp) + } + + // Lastly, requests against an existing resource, use the last request URI + if ps.uri == "" { + m := strings.ToUpper(req.Method) + if m == methodPatch || m == methodPut || m == methodGet { + ps.uri = req.URL.String() + } + } + } + + // Read and interpret the response (saving the Body in case no polling is necessary) + b := &bytes.Buffer{} + err := autorest.Respond(resp, + autorest.ByCopying(b), + autorest.ByUnmarshallingJSON(pt), + autorest.ByClosing()) + resp.Body = ioutil.NopCloser(b) + if err != nil { + return err + } + + // Interpret the results + // -- Terminal states apply regardless + // -- Unknown states are per-service inprogress states + // -- Otherwise, infer state from HTTP status code + if pt.hasTerminated() { + ps.state = pt.state() + } else if pt.state() != "" { + ps.state = operationInProgress + } else { + switch resp.StatusCode { + case http.StatusAccepted: + ps.state = operationInProgress + + case http.StatusNoContent, http.StatusCreated, http.StatusOK: + ps.state = operationSucceeded + + default: + ps.state = operationFailed + } + } + + if ps.state == operationInProgress && ps.uri == "" { + return autorest.NewError("azure", "updatePollingState", "Azure Polling Error - Unable to obtain polling URI for %s %s", resp.Request.Method, resp.Request.URL) + } + + // For failed operation, check for error code and message in + // -- Operation resource + // -- Response + // -- Otherwise, Unknown + if ps.hasFailed() { + if ps.responseFormat == usesOperationResponse { + or := pt.(*operationResource) + ps.code = or.OperationError.Code + ps.message = or.OperationError.Message + } else { + p := pt.(*provisioningStatus) + if p.hasProvisioningError() { + ps.code = p.ProvisioningError.Code + ps.message = p.ProvisioningError.Message + } else { + ps.code = "Unknown" + ps.message = "None" + } + } + } + return nil +} + +func newPollingRequest(resp *http.Response, ps pollingState) (*http.Request, error) { + req := resp.Request + if req == nil { + return nil, autorest.NewError("azure", "newPollingRequest", "Azure Polling Error - Original HTTP request is missing") + } + + reqPoll, err := autorest.Prepare(&http.Request{Cancel: req.Cancel}, + autorest.AsGet(), + autorest.WithBaseURL(ps.uri)) + if err != nil { + return nil, autorest.NewErrorWithError(err, "azure", "newPollingRequest", nil, "Failure creating poll request to %s", ps.uri) + } + + return reqPoll, nil +} |