func logsStackInstance()

in cmd/hub/api/instance.go [782:855]
72 lines of code
21 McCabe index (conditional complexity)

func logsStackInstance(selector, operationId, filename string) error {
	instance, err := stackInstanceBy(selector)
	if err != nil {
		return err
	}
	if instance == nil {
		return error404
	}
	ops := instance.InflightOperations
	if len(ops) == 0 {
		return errors.New("No inflight operations")
	}
	var op InflightOperation
	if operationId == "" {
		op = ops[len(ops)-1]
	} else {
		for i := range ops {
			if operationId == ops[i].Id {
				op = ops[i]
			}
		}
	}
	if op.Id == "" {
		return errors.New("No inflight operation found")
	}
	if op.Location == "" {
		return errors.New("Inflight operation has no location")
	}
	path := fmt.Sprintf("%s/%s?log=true", tasksResource, op.Location)
	code, body, err := get2(hubApi(), path) // TODO stream log into file
	if err != nil {
		return err
	}
	if code != 200 {
		return fmt.Errorf("Got %d HTTP fetching HubCTL Stack Instance log, expected 200 HTTP", code)
	}
	if len(body) == 0 {
		return fmt.Errorf("Got empty HubCTL Stack Instance log")
	}

	if filename == "" {
		filename = fmt.Sprintf("logs.%s.%s.txt", instance.Domain, op.Id)
	}
	var file io.WriteCloser
	if filename == "-" {
		file = os.Stdout
	} else {
		info, _ := os.Stat(filename)
		if info != nil {
			if info.IsDir() {
				filename = fmt.Sprintf("%s/%s", filename, op.Id)
			} else {
				if !config.Force {
					log.Fatalf("Log `%s` exists, use --force / -f to overwrite", filename)
				}
			}
		}
		var err error
		file, err = os.Create(filename)
		if err != nil {
			return fmt.Errorf("Unable to create %s: %v", filename, err)
		}
		defer file.Close()
	}
	written, err := file.Write(body)
	if written != len(body) {
		return fmt.Errorf("Unable to write %s: %v", filename, err)
	}
	if config.Verbose && filename != "-" {
		log.Printf("Wrote %s", filename)
	}

	return nil
}