Debugging in Botpress

3 minutes read

Debugging is a process of finding and resolving bugs in a computer program. We will use VSCode debugging and Botpress logging capability to find and resolve bugs in our bot. Logging in Botpress is an invaluable tool that will provide better visibility into your bots flow. Using logging in your bot can help you find critical things and gain unprecedented insight into how your bot is performing. When we deploy our bot into production, it should run smoothly with no errors or crash as it will affect our customers, but sometimes it might happen that the bot stopped responding because of connection errors, API related errors or because of application logic.

If we provide enough logging into our bot, it will help us walkthrough each step in the log and find out exactly what happened before the error. To add more control we will use debugger keyword in our actions and hooks to add breakpoints and analyze in memory values. Looking at this flow can help us solve the problem. In this post we will see how we can use VScode debugger, Botpress SDK logging and plain JavaScript console.log to log at critical places in our Bot.

Note: debugger keyword should be removed before deploying your bot in a production environment.

We will combine VSCode debugging and Botpress logger to find and fix issues. For logging we will use both Botpress logging panel and browsers debugging console using below two methods

• Botpress SDK
• Javascript console.log

Botpress SDK

Botpress SDK provides logger to log messages into your Botpress panel and it is the recommended logging approach. This provides the following log levels.

• debug
• error
• info
• warn

For example: bp.logger.info('About to push data to MySQL') Check this tutorial.

Javascript console.log

Javascript console.log, provides a logger to display variable state that was defined before this statement and also print text messages that will be valuable to the user, this will mostly come handy when you are trying to enable logging in your custom component. You can check the console logs in browser’s debug console.

Let us reuse and change the bot we created here

/**
   * Validates Email Signature
   * @title Email Signature validation utility
   * @category Utility
   * @author Abhishek Raj Simon
   * @param {string} value - Pass email here
   */
const myAction = async value => {
  const userId = event.target
  const botId = event.botId
  const emailString = value
  const emailfilter = /^\w+[\+\.\w-]*([\w-]+\.)*\w+[\w-]*\.([a-z]{2,4}|\d+)$/i
  
  temp.isEmailValid = emailfilter.test(emailString)
}

return myAction(args.value)

Above action will be used to validate the email signature, but this action has a flaw, which we will try to debug and fix.

Start your Botpress server. Once it is up, trigger your bot through emulator. It will ask you to enter an email address. Please enter a valid email address when prompted and it will try to validate the email signature.

Here it failed, even though we entered a correct email address. Let us try to debug this, by adding 3 additional statements debugger, console.log & bp.logger.info in our ValidateEmailSignature custom action.

debugger
console.log(`IsEmailValid: ${temp.isEmailValid} EmailString: ${emailString}`)
bp.logger.info(`IsEmailValid: ${temp.isEmailValid} EmailString: ${emailString}`);

Let us also enable the file output (out\bp\data\global\botpress.config.json) for our logs by making the fileOutput.enabled: true so that it creates a log file in the Botpress working directory.

Note: This will be useful in your deployment as you cannot see console.log content, when Botpress is running as a background process.

Restart the Botpress server from VSCode’s debug option to start debugging. Since we added a debugger keyword in our custom action, this time it will break on the the debugger line. Here you can inspect the value of temp.isEmailValid variable and we can see that even when we entered correct email address it failed the validation.

As you can see we are receiving proper email address in our custom action, but still the regex test method returns false.

After carefully examining the regex one can find out that a email signature should always have a @ symbol, that is missing in our emailfilter regex. Let us modify our regex to /^\w+[\+\.\w-]*@([\w-]+\.)*\w+[\w-]*\.([a-z]{2,4}|\d+)$/i and trigger the bot again. This time it should properly validate the entered email address.

Here is the correct ValidateEmailSignature action file content

const bodyParser = require("body-parser")

/**
   * Validates Email Signature
   * @title Email Signature validation utility
   * @category Utility
   * @author Abhishek Raj Simon
   * @param {string} value - Pass email here
   */
const myAction = async value => {
  const userId = event.target
  const botId = event.botId
  const emailString = value
  const emailfilter = /^\w+[\+\.\w-]*@([\w-]+\.)*\w+[\w-]*\.([a-z]{2,4}|\d+)$/i
  bp.logger.info(emailString)
  temp.isEmailValid = emailfilter.test(emailString)
  debugger
  console.log(`IsEmailValid: ${temp.isEmailValid} EmailString: ${emailString}`)
  bp.logger.info(`IsEmailValid: ${temp.isEmailValid} EmailString: ${emailString}`);
}

return myAction(args.value)

You can also download the bot export from Github.