Querying Using the Discovery API

Documentation

• Discovery API docs

Supporting Courses

• Node.js Basics: Remember to check out our Node course if you want more help understanding how to write a Node app that can consume an API like this.
• Express Basics: Express is used for the web client code that users interact with.
• REST API Basics: This short course explains how REST APIs (like the Watson APIs) are designed and used.

Final Project Files

This finished code is available for download as a zip or from our GitHub repo. Individual files available for this video:

• .env
• app.js

---

Code for Copy/Paste

.env

# Discovery Service
DISCOVERY_URL=https://gateway.watsonplatform.net/discovery/api
DISCOVERY_COLLECTION_ID=<add your collection ID>
DISCOVERY_ENVIRONMENT_ID=<add your environment ID>
DISCOVERY_USERNAME=<add your username>
DISCOVERY_PASSWORD=<add your password>
DISCOVERY_VERSION_DATE=2017-10-17

# Environment variables
INTENT_CONFIDENCE=0.75

app.js (wrapper)

var discovery = new watsonDiscovery({
  url: process.env.DISCOVERY_URL,
  username: process.env.DISCOVERY_USERNAME || '<username>',
  password: process.env.DISCOVERY_PASSWORD || '<password>',
  version_date: process.env.DISCOVERY_VERSION_DATE,
  version: 'v1'
});

var intentConfidence = process.env.INTENT_CONFIDENCE;

app.js (else if)

    // Check the confidence level and forward text to the Discovery service, if needed
    else if (data.input.text !== "start conversation" && data.intents.length > 0 && data.intents[0].confidence < intentConfidence) {
      // Log the Conversation repsonse for us to explore
      console.log("Logging the response from the Conversation service:");
      console.log(data);

      // return discovery data
      var response = {
        "input": {"text": req.body.input.text},
        "context": data.context,
        "output": {"text": []}
      };

      var version_date = process.env.DISCOVERY_VERSION_DATE;
      var environment_id = process.env.DISCOVERY_ENVIRONMENT_ID;
      var collection_id = process.env.DISCOVERY_COLLECTION_ID;

      discovery.query({
          version_date: version_date,
          environment_id: environment_id,
          collection_id: collection_id,
          query: req.body.input.text,
          count: 5
        },
        (err, data) => {
          if (err) {
            console.log("Error: ");
            console.log(err);
            return res.status(err.code || 500).json(err);
          }

          if (data.results.length > 0) {
            for(var i = 0; i < data.results.length; i++) {
              response.output.text.push(data.results[i]); // keep this use-case agnostic;
            }
          } else {
            response.output.text.push("I cannot find an answer to your question.");
          }

          return res.json(response);
        }
      );
    }