Example #1
0
// makeWatchHandler returns a handler for the given watch
func makeWatchHandler(logOutput io.Writer, params interface{}) watch.HandlerFunc {
	script := params.(string)
	logger := log.New(logOutput, "", log.LstdFlags)
	fn := func(idx uint64, data interface{}) {
		// Create the command
		cmd, err := ExecScript(script)
		if err != nil {
			logger.Printf("[ERR] agent: Failed to setup watch: %v", err)
			return
		}
		cmd.Env = append(os.Environ(),
			"CONSUL_INDEX="+strconv.FormatUint(idx, 10),
		)

		// Collect the output
		output, _ := circbuf.NewBuffer(WatchBufSize)
		cmd.Stdout = output
		cmd.Stderr = output

		// Setup the input
		var inp bytes.Buffer
		enc := json.NewEncoder(&inp)
		if err := enc.Encode(data); err != nil {
			logger.Printf("[ERR] agent: Failed to encode data for watch '%s': %v", script, err)
			return
		}
		cmd.Stdin = &inp

		// Run the handler
		if err := cmd.Run(); err != nil {
			logger.Printf("[ERR] agent: Failed to invoke watch handler '%s': %v", script, err)
		}

		// Get the output, add a message about truncation
		outputStr := string(output.Bytes())
		if output.TotalWritten() > output.Size() {
			outputStr = fmt.Sprintf("Captured %d of %d bytes\n...\n%s",
				output.Size(), output.TotalWritten(), outputStr)
		}

		// Log the output
		logger.Printf("[DEBUG] agent: watch handler '%s' output: %s", script, outputStr)
	}
	return fn
}
Example #2
0
// check is invoked periodically to perform the script check
func (c *CheckMonitor) check() {
	// Create the command
	cmd, err := ExecScript(c.Script)
	if err != nil {
		c.Logger.Printf("[ERR] agent: failed to setup invoke '%s': %s", c.Script, err)
		c.Notify.UpdateCheck(c.CheckID, structs.HealthCritical, err.Error())
		return
	}

	// Collect the output
	output, _ := circbuf.NewBuffer(CheckBufSize)
	cmd.Stdout = output
	cmd.Stderr = output

	// Start the check
	if err := cmd.Start(); err != nil {
		c.Logger.Printf("[ERR] agent: failed to invoke '%s': %s", c.Script, err)
		c.Notify.UpdateCheck(c.CheckID, structs.HealthCritical, err.Error())
		return
	}

	// Wait for the check to complete
	errCh := make(chan error, 2)
	go func() {
		errCh <- cmd.Wait()
	}()
	go func() {
		time.Sleep(30 * time.Second)
		errCh <- fmt.Errorf("Timed out running check '%s'", c.Script)
	}()
	err = <-errCh

	// Get the output, add a message about truncation
	outputStr := string(output.Bytes())
	if output.TotalWritten() > output.Size() {
		outputStr = fmt.Sprintf("Captured %d of %d bytes\n...\n%s",
			output.Size(), output.TotalWritten(), outputStr)
	}

	c.Logger.Printf("[DEBUG] agent: check '%s' script '%s' output: %s",
		c.CheckID, c.Script, outputStr)

	// Check if the check passed
	if err == nil {
		c.Logger.Printf("[DEBUG] agent: Check '%v' is passing", c.CheckID)
		c.Notify.UpdateCheck(c.CheckID, structs.HealthPassing, outputStr)
		return
	}

	// If the exit code is 1, set check as warning
	exitErr, ok := err.(*exec.ExitError)
	if ok {
		if status, ok := exitErr.Sys().(syscall.WaitStatus); ok {
			code := status.ExitStatus()
			if code == 1 {
				c.Logger.Printf("[WARN] agent: Check '%v' is now warning", c.CheckID)
				c.Notify.UpdateCheck(c.CheckID, structs.HealthWarning, outputStr)
				return
			}
		}
	}

	// Set the health as critical
	c.Logger.Printf("[WARN] agent: Check '%v' is now critical", c.CheckID)
	c.Notify.UpdateCheck(c.CheckID, structs.HealthCritical, outputStr)
}