func()

in appinsights/transmitter.go [61:135]
58 lines of code
14 McCabe index (conditional complexity)

func (transmitter *httpTransmitter) Transmit(payload []byte, items telemetryBufferItems) (*transmissionResult, error) {
	diagnosticsWriter.Printf("--------- Transmitting %d items ---------", len(items))
	startTime := time.Now()

	// Compress the payload
	var postBody bytes.Buffer
	gzipWriter := gzip.NewWriter(&postBody)
	if _, err := gzipWriter.Write(payload); err != nil {
		diagnosticsWriter.Printf("Failed to compress the payload: %s", err.Error())
		gzipWriter.Close()
		return nil, err
	}

	gzipWriter.Close()

	req, err := http.NewRequest("POST", transmitter.endpoint, &postBody)
	if err != nil {
		return nil, err
	}

	req.Header.Set("Content-Encoding", "gzip")
	req.Header.Set("Content-Type", "application/x-json-stream")
	req.Header.Set("Accept-Encoding", "gzip, deflate")

	resp, err := transmitter.client.Do(req)
	if err != nil {
		diagnosticsWriter.Printf("Failed to transmit telemetry: %s", err.Error())
		return nil, err
	}

	defer resp.Body.Close()

	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		diagnosticsWriter.Printf("Failed to read response from server: %s", err.Error())
		return nil, err
	}

	duration := time.Since(startTime)

	result := &transmissionResult{statusCode: resp.StatusCode}

	// Grab Retry-After header
	if retryAfterValue, ok := resp.Header[http.CanonicalHeaderKey("Retry-After")]; ok && len(retryAfterValue) == 1 {
		if retryAfterTime, err := time.Parse(time.RFC1123, retryAfterValue[0]); err == nil {
			result.retryAfter = &retryAfterTime
		}
	}

	// Parse body, if possible
	response := &backendResponse{}
	if err := json.Unmarshal(body, &response); err == nil {
		result.response = response
	}

	// Write diagnostics
	if diagnosticsWriter.hasListeners() {
		diagnosticsWriter.Printf("Telemetry transmitted in %s", duration)
		diagnosticsWriter.Printf("Response: %d", result.statusCode)
		if result.response != nil {
			diagnosticsWriter.Printf("Items accepted/received: %d/%d", result.response.ItemsAccepted, result.response.ItemsReceived)
			if len(result.response.Errors) > 0 {
				diagnosticsWriter.Printf("Errors:")
				for _, err := range result.response.Errors {
					if err.Index < len(items) {
						diagnosticsWriter.Printf("#%d - %d %s", err.Index, err.StatusCode, err.Message)
						diagnosticsWriter.Printf("Telemetry item:\n\t%s", string(items[err.Index:err.Index+1].serialize()))
					}
				}
			}
		}
	}

	return result, nil
}