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
}
// 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
}