Procedure

To add the webhook details, complete the following steps:

1. In your assistant, go to Environments and open the environment where you want to configure the webhook.

2. Click the icon to open the environment settings.

3. On the Environment settings page, click Pre-message webhook.

   For the Classic experience, complete the following steps:

   • For the assistant that you want to configure, click the icon, and then choose Settings.

   • Click Webhooks > Pre-message webhook.

4. Set the Pre-message webhook switch to Enabled.

5. In the Synchronous event, select from one of the following options:

   • Continue processing user input without webhook update if there is an error.

   • Return an error to the client if the webhook call fails.

   For more information see, Configuring webhook error handling for preprocessing.

6. In the URL field, add the URL for the external application to which you want to send HTTP POST request callouts.

   For example, you might write a Cloud Functions web action that checks if a message is in a language other than English, and send it to the Language Translator service to convert it to English. Specify the URL for your web action, as in this example:

   https://us-south.functions.cloud.ibm.com/api/v1/web/my_org_dev/default/translateToEnglish.json
   

   You must specify a URL that uses the SSL protocol, so specify a URL that begins with https.

7. To configure the authentication for pre-message webhooks, click Edit authentication. For detailed instructions, see Defining the authentication method for pre-message and post-message webhooks.

   • For the Classic experience, fill in the Secret field. For more information, see Adding a secret for the Classic experience only.

8. In the Timeout field, specify the time duration (in seconds) that you want the assistant to wait for a response from the webhook before it returns an error. The timeout duration cannot be shorter than 1 second or longer than 30 seconds.

9. In the Headers section, click Add header + to add any headers that you want to pass to the service, one at a time.

   For the Classic experience, the service automatically sends an authorization header with a JWT. If you want to handle the authorization yourself, add your own authorization header and the service uses it instead.

   If the external application that you call returns a response, it might be able to send a response in different formats. The webhook requires that the response is formatted in JSON. The following table illustrates how to add a header to indicate that you want the resulting value to be returned is in JSON format.

   Header example

   Header name	Header value
   Content-Type	application/json

10. After you save the header value, the string is replaced by asterisks and can't be viewed again.

11. Your webhook details are saved automatically.

Testing the webhook

Do extensive testing of your webhook before you enable it for an assistant that is used in a production environment.

The webhook is triggered when a message is sent to your assistant to be processed.

Troubleshooting the webhook

The following error codes can help you track down the cause of issues you might encounter. If you have a web chat integration, for example, you know that your webhook has an issue if every test message you submit returns a message such as There is an error with the message you just sent, but feel free to ask me something else. If this message is displayed, use a REST API tool, such as cURL, to send a test /message API request, so you can see the error code and the full message that is returned.

Webhook security for the Classic experience only

For the Classic experience, authenticate the webhook request by verifying the JSON Web Token (JWT) that is sent with the request. The webhook microservice automatically generates a JWT and sends it in the Authorization header with each webhook call:

• For new webhooks or webhooks updated through Edit authentication, the authorization header is ignored.

• For existing webhooks with a saved authentication header, the Edit authentication option is disabled.

• Updating an existing webhook to use the new authentication configuration will change its behavior.

If you need to test the JWT verification, you can add code to the external service. For example, if you specify purple unicorn in the Secret field, you can use the following code:

const jwt = require('jsonwebtoken');
...
const token = request.headers.authentication; // grab the "Authentication" header
try {
  const decoded = jwt.verify(token, 'purple unicorn');
} catch(err) {
  // error thrown if token is invalid
}

Request body

It is useful to know the format of the request body of the pre-message webhook so that your external code can process it.

The payload contains the request body of the /message (stateful or stateless) v2 API request. The event name message_received indicates that the request is generated by the pre-message webhook. For more information about the message request body, see the API reference.

{
  "payload" : { Copy of request body sent to /message }
  "event": {
      "name": "message_received"
   }
}

Skipping the assistant processing for Classic experience only

For the Classic experience, enhancements to pre-message webhooks allow watsonx Assistant to skip message processing and directly return the response from the webhook. This functionality is activated by setting the x-watson-assistant-webhook-returnheader in the webhook's HTTP response.

Response body

The service that receives the POST request from the webhook must return a JSON object (Accept: application/json).

The response body must have the following structure:

{
  "payload": {
    ...
  }
}

The response payload must include the payload from the request body. Your code can modify property values or modify context variables, but the returned message payload must follow the message method schema. For more information, see API reference.

Example 1

This example shows you how to check the language of the input text, and append the language information to the input text string.

In the pre-message webhook configuration page, the following values are specified:

For the Classic experience, there is no value in the Secret field.

• URL: https://us-south.functions.appdomain.cloud/api/v1/web/e97d2516-5ce4-4fd9-9d05-acc3dd8ennn/default/check_language
• Header name: Content-Type
• Header value: application/json

The pre-message webhook calls an IBM Cloud Functions web action name check_language.

The node.js code in the check_language web action looks as follows.

let rp = require("request-promise");

function main(params) {
console.log(JSON.stringify(params))
if (params.payload.input.text !== '') {
  // Send a request to the Watson Language Translator service to check the language of the input text.
const options = { method: 'POST',
  url: 'https://api.us-south.language-translator.watson.cloud.ibm.com/instances/572b37be-09f4-4704-b693-3bc63869nnnn/v3/identify?version=2018-05-01',
  auth: {
           'username': 'apikey',
           'password': 'nnn'
       },
headers: {
    "Content-Type":"text/plain"
},
  body: [
          params.payload.input.text
  ],
  json: true,
};
     return rp(options)
    .then(res => {
        params.payload.context.skills["actions skill"].user_defined["language"] = res.languages[0].language;
        console.log(JSON.stringify(params))
        //Append "in" plus "the language code" to the input text, surrounded by parentheses.
        const response = {
            body : {
                payload : {
                    input : {
                        text : params.payload.input.text + ' ' + '(in ' + res.languages[0].language + ')'
                    },
                },
            },
        };
        return response;
})
}
return { 
    body : params
}
};

To test the webhook, click Preview. Submit the text Buenos días. The assistant probably can't understand the input, and returns the response from your Anything else node. However, if you go to the Analyze page of your assistant and open Conversations, you can see what was submitted. Check the most recent user conversation. The log shows that the user input is Buenos días (in es). The es in parentheses represents the language code for Spanish, so the webhook worked and recognized that the submitted text was a Spanish phrase.

Example 2

This example shows you how to check the language of the incoming message, and if it's not English, translate it into English before you submit it to the assistant.

Define a sequence of web actions in IBM Cloud Functions. The first action in the sequence checks the language of the incoming text. The second action in the sequence translates the text from its original language into English.

In the pre-message webhook configuration page, the following values are specified:

For the Classic experience, there is no value in the Secret field.

• URL: https://us-south.functions.appdomain.cloud/api/v1/web/e97d2516-5ce4-4fd9-9d05-acc3dd8ennn/default/translation_sequence
• Header name: Content-Type
• Header value: application/json

The node.js code for the first web action in your sequence looks as follows:

let rp = require("request-promise");

function main(params) {
console.log(JSON.stringify(params))
if (params.payload.input.text !== '') {
const options = { method: 'POST',
  url: 'https://api.us-south.language-translator.watson.cloud.ibm.com/instances/572b37be-09f4-4704-b693-3bc63869nnnn/v3/identify?version=2018-05-01',
  auth: {
           'username': 'apikey',
           'password': 'nnn'
       },
headers: {
    "Content-Type":"text/plain"
},
  body: [
          params.payload.input.text
  ],
  json: true,
};
     return rp(options)
    .then(res => {
      //Set the language property of the incoming message to the language that was identified by Watson Language Translator. 
        params.payload.context.skills["actions skill"].user_defined["language"] = res.languages[0].language;
        console.log(JSON.stringify(params))
        return params;
})
}
else {
    params.payload.context.skills["actions skill"].user_defined["language"] = 'none'
    return params
}
};

The second web action in the sequence sends the text to the Watson Language Translator service to translate the input text from the language that was identified in the previous web action into English. The translated string is then sent to your assistant instead of the original text.

The node.js code for the second action in your sequence looks as follows:

let rp = require("request-promise");

function main(params) {
console.log(JSON.stringify(params))
//If the the incoming message is not null and is not English, translate it.
if ((params.payload.context.skills["actions skill"].user_defined.language !== 'en') && (params.payload.context.skills["actions skill"].user_defined.language !== 'none')) {
const options = { method: 'POST',
  url: 'https://api.us-south.language-translator.watson.cloud.ibm.com/instances/572b37be-09f4-4704-b693-3bc63869nnnn/v3/translate?version=2018-05-01',
  auth: {
           'username': 'apikey',
           'password': 'nnn'
       },
  headers: {
    "Content-Type":"application/json"
  },
       //The body includes the parameters that are required by the Language Translator service, the text to translate and the target language to translate it into.
  body: { 
      text: [ 
          params.payload.input.text
          ],
          target: 'en' 
  },
  json: true 
};
     return rp(options)
    .then(res => {
        params.payload.context.skills["actions skill"].user_defined["original_input"] = params.payload.input.text;
        const response = {
            body : {
                payload : {
                    "context" : params.payload.context,
                    "input" : {
                        "text" : res.translations[0].translation,
                        "options" : {
                            "export" : true
                            }
                    },
                },
            },
        };
    return response
})
}
return { 
    body : params
    }
};

When you test the webhook in the preview panel, you can submit Buenos días, and the assistant responds as if you said Good morning in English. In fact, when you check the Analyze page of your assistant and open Conversations, the log shows that the user input was Good morning.

You can add a post-message webhook to translate the message's response back into the customer's language before it is displayed. For more information, see Example 2.

Example 3

This example shows how to compose a webhook response to let watsonx Assistant skip processing the message and directly return the webhook's response.

function main(params) {
  // Your custom logic to determine the response
  let responseText = "This response is directly from the pre-message webhook.";

  const response = {
    headers: {
      "X-Watson-Assistant-Webhook-Return": "true"
    },
    body: {
      output: {
        generic: [
          {
            response_type: "text",
            text: responseText
          }
        ]
      }
    }
  };

  return response;
}

Removing the webhook

If you decide that you do not want to preprocess customer input with a webhook, complete the following steps:

1. In your assistant, go to Environments and open the environment where you want to remove the webhook.

2. Click the icon to open the environment settings.

3. On the Environment settings page, click Pre-message webhook.

   For the Classic experience, complete the following steps:

   • For the assistant that you want to configure, click the icon, and then choose Settings.

   • Click Webhooks > Pre-message webhook.

4. Do one of the following steps:

   • To stop calling a webhook to process every incoming message, set the Pre-message webhook switch to Disabled.

   • To change the webhook that you want to call, click Delete webhook.