gsheet-to-json-csv_download.go

func Download(url string, filename string, timeout int64) *u.ErrorResponse {
	u.GeneralLogger.Println("Downloading", url, "...")
	client := http.Client{
		Timeout: time.Duration(timeout * int64(time.Second)),
	}
	resp, err := client.Get(url)
	if err != nil {
		u.ErrorLogger.Println("Cannot download file from the given url", err)
		return u.ReturnErrorResponse(err, "Cannot download file from the given url")
	}

	if resp.StatusCode != 200 {
		u.ErrorLogger.Printf("Response from the URL was %d, but expecting 200", resp.StatusCode)
		return u.ReturnErrorResponse(
			errors.New("Response returned with a status different from 200"),
			"Response returned with a status different from 200",
		)
	}
	if resp.Header["Content-Type"][0] != "text/csv" {
		u.ErrorLogger.Printf("The file downloaded has content type '%s', expected 'text/csv'.", resp.Header["Content-Type"])
		return u.ReturnErrorResponse(
			errors.New("Downloaded file didn't contain the expected content-type: 'text/csv'"),
			"Downloaded file didn't contain the expected content-type: 'text/csv'",
		)
	}

	b, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		u.ErrorLogger.Println("Cannot read Body of Response", err)
		return u.ReturnErrorResponse(err, "Cannot read Body of Response")
	}

	err = ioutil.WriteFile(filename, b, 0644)
	if err != nil {
		u.ErrorLogger.Println("Cannot write to file", err)
		return u.ReturnErrorResponse(err, "Cannot write to file")
	}

	u.GeneralLogger.Println("Doc downloaded in ", filename)

	return u.ReturnErrorResponse(nil, "")
}