# Watson APIs Node.js SDK

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Node.js client library to use the Watson APIs.

<details>
  <summary>Table of Contents</summary>

  * [Before you begin](#before-you-begin)
  * [Installation](#installation)
  * [Usage](#usage)
  * [Client-side usage](#client-side-usage)
  * [Authentication](#authentication)
    * [IAM](#iam)
    * [Username and password](#username-and-password)
    * [API key](#api-key)
  * [Sending request headers](#sending-request-headers)
  * [Parsing HTTP response](#parsing-http-response)
  * [Data collection opt-out](#data-collection-opt-out)
  * [Documentation](#documentation)
  * [Questions](#questions)
  * [IBM Watson services](#ibm-watson-services)
    * [Authorization](#authorization)
    * [Assistant v2](#assistant-v2)
    * [Assistant v1](#assistant-v1)
    * [Discovery](#discovery)
    * [Language Translator v3](#language-translator-v3)
    * [Language Translator v2](#language-translator-v2)
    * [Natural Language Classifier](#natural-language-classifier)
    * [Natural Language Understanding](#natural-language-understanding)
    * [Personality Insights](#personality-insights)
    * [Speech to Text](#speech-to-text)
    * [Text to Speech](#text-to-speech)
    * [Tone Analyzer](#tone-analyzer)
    * [Visual Recognition](#visual-recognition)
  * [Composing Services](#composing-services)
  * [Debug](#debug)
  * [Tests](#tests)
  * [License](#license)
  * [Contributing](#contributing)

</details>

## Before you begin
* You need an [IBM Cloud][ibm-cloud-onboarding] account.

## Installation

```sh
npm install watson-developer-cloud
```

## Usage

The [examples][examples] folder has basic and advanced examples. The examples within each service assume that you already have [service credentials](#getting-credentials). 

Credentials are checked for in the following order:

1. Hard-coded or programatic credentials passed to the service constructor

2. Environment variables:
- `SERVICE_NAME_USERNAME` and `SERVICE_NAME_PASSWORD` environment properties (or `SERVICE_NAME_API_KEY` when appropriate) and, optionally, `SERVICE_NAME_URL`
- If using IAM: `SERVICE_NAME_IAM_APIKEY` and optionally `SERVICE_NAME_IAM_URL`, or `SERVICE_NAME_IAM_ACCESS_TOKEN`

3. IBM-Cloud-supplied credentials (via the `VCAP_SERVICES` JSON-encoded environment property)

If you run your app in IBM Cloud, the SDK gets credentials from the [`VCAP_SERVICES`][vcap_services] environment variable. 

### Client-side usage

See the `examples/` folder for [Browserify](http://browserify.org/) and [Webpack](http://webpack.github.io/) client-side SDK examples (with server-side generation of auth tokens.)

Note: not all services currently support CORS, and therefore not all services can be used client-side.
Of those that do, most require an auth token to be generated server-side via the [Authorization Service](#authorization).

## Authentication
Watson services are migrating to token-based Identity and Access Management (IAM) authentication.

- With some service instances, you authenticate to the API by using **[IAM](#iam)**.
- In other instances, you authenticate by providing the **[username and password](#username-and-password)** for the service instance.

### Getting credentials
To find out which authentication to use, view the service credentials. You find the service credentials for authentication the same way for all Watson services:

1. Go to the IBM Cloud [Dashboard](https://console.bluemix.net/dashboard/apps?category=ai) page.
1. Either click an existing Watson service instance or click [**Create resource > AI**](https://console.bluemix.net/catalog/?category=ai) and create a service instance.
1. Click **Show** to view your service credentials.
1. Copy the `url` and either `apikey` or `username` and `password`.

### IAM

Some services use token-based Identity and Access Management (IAM) authentication. IAM authentication uses a service API key to get an access token that is passed with the call. Access tokens are valid for approximately one hour and must be regenerated.

You supply either an IAM service **API key** or an **access token**:

- Use the API key to have the SDK manage the lifecycle of the access token. The SDK requests an access token, ensures that the access token is valid, and refreshes it if necessary.
- Use the access token if you want to manage the lifecycle yourself. For details, see [Authenticating with IAM tokens](https://console.bluemix.net/docs/services/watson/getting-started-iam.html). If you want to switch to API key, override your stored IAM credentials with an IAM API key.

#### Supplying the IAM API key

```js
// in the constructor, letting the SDK manage the IAM token
const discovery = new DiscoveryV1({
  url: '<service_url>',
  version: '<version-date>',
  iam_apikey: '<iam_api_key>',
  iam_url: '<iam_url>', // optional - the default value is https://iam.bluemix.net/identity/token
});
```

#### Supplying the access token

```js
// in the constructor, assuming control of managing IAM token
const discovery = new DiscoveryV1({
  url: '<service_url>',
  version: '<version-date>',
  iam_access_token: '<access-token>'
});
```

```js
// after instantiation, assuming control of managing IAM token
const discovery = new DiscoveryV1({
  url: '<service_url>',
  version: '<version-date>'
});

discovery.setAccessToken('<access-token>')
```

### Username and password

```javascript
var DiscoveryV1 = require('watson-developer-cloud/discovery/v1');

var discovery = new DiscoveryV1({
    version: '{version}',
    username: '{username}',
    password: '{password}'
  });
```

### Sending request headers

Custom headers can be passed with any request. Each method has an optional parameter `headers` which can be used to pass in these custom headers, which can override headers that we use as parameters.

For example, this is how you can pass in custom headers to Watson Assistant service. In this example, the `'custom'` value for `'Accept-Language'` will override the default header for `'Accept-Language'`, and the `'Custom-Header'` while not overriding the default headers, will additionally be sent with the request.

```js
var assistant = new watson.AssistantV1({
/* username, password, version, url, etc... */
});

assistant.message({
  workspace_id: 'something',
  input: {'text': 'Hello'},
  headers: {
    'Custom-Header': 'custom',
    'Accept-Language': 'custom'
  
  }
},  function(err, result, response) {
  if (err)
    console.log('error:', err);
  else
    console.log(JSON.stringify(result, null, 2));
});

```

### Parsing HTTP response

To retrieve the HTTP response, all methods can be called with a callback function with three parameters, with the third being the response. Users for example may retrieve the response headers with this usage pattern.

Here is an example of how to access the response headers for Watson Assistant:

```js
var assistant = new watson.AssistantV1({
/* username, password, version, url, etc... */
});

assistant.message(params,  function(err, result, response) {
  if (err)
    console.log('error:', err);
  else
    console.log(response.headers);
});

```

### Data collection opt-out

By default, [all requests are logged](https://console.bluemix.net/docs/services/watson/getting-started-logging.html). This can be disabled of by setting the `X-Watson-Learning-Opt-Out` header when creating the service instance:

```js
var myInstance = new watson.WhateverServiceV1({
  /* username, password, version, url, etc... */
  headers: {
    "X-Watson-Learning-Opt-Out": true
  }
});
```

### Configuring the HTTP client

The HTTP client can be configured to disable SSL verification. Note that this has serious security implications - only do this if you really mean to! ⚠️

To do this, set `disable_ssl_verification` to `true` in the service constructor, like below:

```
const discovery = new DiscoveryV1({
  url: '<service_url>',
  version: '<version-date>',
  iam_apikey: '<iam_api_key>',
  disable_ssl_verification: true, // this will disable SSL verification for any request made with this object
});
```

## Documentation

You can find links to the documentation at https://console.bluemix.net/developer/watson/documentation. Find the service that you're interested in, click **API reference**, and then select the **Node** tab.

There are also auto-generated JSDocs available at http://watson-developer-cloud.github.io/node-sdk/master/

## Questions

If you are having difficulties using the APIs or have a question about the Watson services, please ask a question at [dW Answers](https://developer.ibm.com/answers/questions/ask/?topics=watson) or [Stack Overflow](http://stackoverflow.com/questions/ask?tags=ibm-watson-cognitive).

## IBM Watson services

### Authorization

The Authorization service can generate auth tokens for situations where providing the service username/password is undesirable.

Tokens are valid for 1 hour and may be sent using the `X-Watson-Authorization-Token` header or the `watson-token` query param.
Note that the token is supplied URL-encoded, and will not be accepted if it is double-encoded in a querystring.

> _NOTE_: Authenticating with the `X-Watson-Authorization-Token` header or the `watson-token` query param is now deprecated. The token continues to work with Cloud Foundry services, but is not supported for services that use Identity and Access Management (IAM) authentication. For details see [Authenticating with IAM tokens](https://console.bluemix.net/docs/services/watson/getting-started-iam.html#iam) or the README in the IBM Watson SDK you use.
The Authorization SDK now supports returning IAM Access Tokens when instantiated with an IAM API key.

```javascript
var watson = require('watson-developer-cloud');

// to get an IAM Access Token
var authorization = new watson.AuthorizationV1({
  iam_apikey: '<Service API key>',
  iam_url: '<IAM endpoint URL - OPTIONAL>',
});

authorization.getToken(function (err, token) {
  if (!token) {
    console.log('error:', err);
  } else {
    // Use your token here
  }
});

// to get a Watson Token - NOW DEPRECATED
var authorization = new watson.AuthorizationV1({
  username: '<Text to Speech username>',
  password: '<Text to Speech password>',
  url: 'https://stream.watsonplatform.net/authorization/api', // Speech tokens
});

authorization.getToken({
  url: 'https://stream.watsonplatform.net/text-to-speech/api'
},
function (err, token) {
  if (!token) {
    console.log('error:', err);
  } else {
    // Use your token here
  }
});
```

### Assistant v2

> Watson Assistant v2 API is released in beta. For details, see the ["Introducing Watson Assistant"](https://www.ibm.com/blogs/watson/2018/03/the-future-of-watson-conversation-watson-assistant/) blog post.

Use the [Assistant][conversation] service to determine the intent of a message.

Note: You must first create a workspace via IBM Cloud. See [the documentation](https://console.bluemix.net/docs/services/conversation/index.html#about) for details.

```js
var AssistantV2 = require('watson-developer-cloud/assistant/v2');

var assistant = new AssistantV2({
  username: '<username>',
  password: '<password>',
  url: 'https://gateway.watsonplatform.net/assistant/api/',
  version: '2018-09-19'
});

assistant.message(
  {
    input: { text: "What's the weather?" },
    assistant_id: '<assistant id>',
    session_id: '<session id>',
  },
  function(err, response) {
    if (err) {
      console.error(err);
    } else {
      console.log(JSON.stringify(response, null, 2));
    }
  }
);
```

### Assistant v1

Use the [Assistant][conversation] service to determine the intent of a message.

Note: You must first create a workspace via IBM Cloud. See [the documentation](https://console.bluemix.net/docs/services/conversation/index.html#about) for details.

```js
var AssistantV1 = require('watson-developer-cloud/assistant/v1');

var assistant = new AssistantV1({
  username: '<username>',
  password: '<password>',
  url: 'https://gateway.watsonplatform.net/assistant/api/',
  version: '2018-02-16'
});

assistant.message(
  {
    input: { text: "What's the weather?" },
    workspace_id: '<workspace id>'
  },
  function(err, response) {
    if (err) {
      console.error(err);
    } else {
      console.log(JSON.stringify(response, null, 2));
    }
  }
);
```


### Conversation

This service has been renamed to Assistant.

### Discovery

Use the [Discovery Service][discovery] to search and analyze structured and unstructured data.

```javascript
var DiscoveryV1 = require('watson-developer-cloud/discovery/v1');

var discovery = new DiscoveryV1({
  username: '<username>',
  password: '<password>',
  url: 'https://gateway.watsonplatform.net/discovery/api/',
  version: '2017-09-01'
});

discovery.query(
  {
    environment_id: '<environment_id>',
    collection_id: '<collection_id>',
    query: 'my_query'
  },
  function(err, response) {
    if (err) {
      console.error(err);
    } else {
      console.log(JSON.stringify(response, null, 2));
    }
  }
);

```
### Language Translator v3

Translate text from one language to another or idenfity a language using the [Language Translator][language_translator] service.

```javascript
const LanguageTranslatorV3 = require('watson-developer-cloud/language-translator/v3');

const languageTranslator = new LanguageTranslatorV3({
  iam_apikey: '<apikey>',
  url: 'https://gateway.watsonplatform.net/language-translator/api/',
  version: 'YYYY-MM-DD',
});

languageTranslator.translate(
  {
    text: 'A sentence must have a verb',
    source: 'en',
    target: 'es'
  },
  function(err, translation) {
    if (err)  {
      console.log('error:', err);
    } else  {
      console.log(JSON.stringify(translation, null, 2));
  }
);

languageTranslator.identify(
  {
    text:
      'The language translator service takes text input and identifies the language used.'
  },
  function(err, language) {
    if (err)  {
      console.log('error:', err);
    } else {
      console.log(JSON.stringify(language, null, 2));
    }
  }
);
```

### Language Translator v2

**Note:** Language Translator v3 is now available. The v2 Language Translator API will no longer be available after July 31, 2018. To take advantage of the latest service enhancements, migrate to the v3 API. View the [Migrating to Language Translator v3](https://console.bluemix.net/docs/services/language-translator/migrating.html) page for more information.

Translate text from one language to another or idenfity a language using the [Language Translator][language_translator] service.

```javascript
var LanguageTranslatorV2 = require('watson-developer-cloud/language-translator/v2');

var languageTranslator = new LanguageTranslatorV2({
  username: '<username>',
  password: '<password>',
  url: 'https://gateway.watsonplatform.net/language-translator/api/'
});

languageTranslator.translate(
  {
    text: 'A sentence must have a verb',
    source: 'en',
    target: 'es'
  },
  function(err, translation) {
    if (err)  {
      console.log('error:', err);
    } else  {
      console.log(JSON.stringify(translation, null, 2));
  }
);

languageTranslator.identify(
  {
    text:
      'The language translator service takes text input and identifies the language used.'
  },
  function(err, language) {
    if (err)  {
      console.log('error:', err);
    } else {
      console.log(JSON.stringify(language, null, 2));
    }
  }
);
```


### Natural Language Classifier

Use [Natural Language Classifier](https://console.bluemix.net/docs/services/natural-language-classifier/getting-started.html) service to create a classifier instance by providing a set of representative strings and a set of one or more correct classes for each as training. Then use the trained classifier to classify your new question for best matching answers or to retrieve next actions for your application.

```javascript
var NaturalLanguageClassifierV1 = require('watson-developer-cloud/natural-language-classifier/v1');

var classifier = new NaturalLanguageClassifierV1({
  username: '<username>',
  password: '<password>',
  url: 'https://gateway.watsonplatform.net/natural-language-classifier/api/'
});

classifier.classify(
  {
    text: 'Is it sunny?',
    classifier_id: '<classifier-id>'
  },
  function(err, response) {
    if (err) {
      console.log('error:', err);
    } else {
      console.log(JSON.stringify(response, null, 2));
    }
  }
);
```

See this [example](https://github.com/watson-developer-cloud/node-sdk/blob/master/examples/natural_language_classifier.v1.js) to learn how to create a classifier.


### Natural Language Understanding

Use Natural Language Understanding is a collection of natural language processing APIs that help you understand sentiment,
 keywords, entities, high-level concepts and more.

```javascript
var fs = require('fs');
var NaturalLanguageUnderstandingV1 = require('watson-developer-cloud/natural-language-understanding/v1.js');

var nlu = new NaturalLanguageUnderstandingV1({
  username: '<username>',
  password: '<password>',
  version: '2018-04-05',
  url: 'https://gateway.watsonplatform.net/natural-language-understanding/api/'
});

nlu.analyze(
  {
    html: file_data, // Buffer or String
    features: {
      concepts: {},
      keywords: {}
    }
  },
  function(err, response) {
    if (err) {
      console.log('error:', err);
    } else {
      console.log(JSON.stringify(response, null, 2));
    }
  }
);
```


### Personality Insights

Analyze text in English and get a personality profile by using the
[Personality Insights][personality_insights] service.

```javascript
var PersonalityInsightsV3 = require('watson-developer-cloud/personality-insights/v3');

var personalityInsights = new PersonalityInsightsV3({
  username: '<username>',
  password: '<password>',
  version: '2016-10-19',
  url: 'https://gateway.watsonplatform.net/personality-insights/api/'
});

personalityInsights.profile(
  {
    content: 'Enter more than 100 unique words here...',
    content_type: 'text/plain',
    consumption_preferences: true
  },
  function(err, response) {
    if (err) {
      console.log('error:', err);
    } else {
      console.log(JSON.stringify(response, null, 2));
    }
  }
);
```


### Speech to Text

Use the [Speech to Text][speech_to_text] service to recognize the text from a `.wav` file.

```javascript
var SpeechToTextV1 = require('watson-developer-cloud/speech-to-text/v1');
var fs = require('fs');

var speechToText = new SpeechToTextV1({
  username: '<username>',
  password: '<password>',
  url: 'https://stream.watsonplatform.net/speech-to-text/api/'
});

var params = {
  // From file
  audio: fs.createReadStream('./resources/speech.wav'),
  content_type: 'audio/l16; rate=44100'
};

speechToText.recognize(params, function(err, res) {
  if (err)
    console.log(err);
  else
    console.log(JSON.stringify(res, null, 2));
});

// or streaming
fs.createReadStream('./resources/speech.wav')
  .pipe(speechToText.recognizeUsingWebSocket({ content_type: 'audio/l16; rate=44100' }))
  .pipe(fs.createWriteStream('./transcription.txt'));
```


### Text to Speech

Use the [Text to Speech][text_to_speech] service to synthesize text into a .wav file.

```js
var TextToSpeechV1 = require('watson-developer-cloud/text-to-speech/v1');
var fs = require('fs');

var textToSpeech = new TextToSpeechV1({
  username: '<username>',
  password: '<password>',
  url: 'https://stream.watsonplatform.net/text-to-speech/api/'
});

var params = {
  text: 'Hello from IBM Watson',
  voice: 'en-US_AllisonVoice', // Optional voice
  accept: 'audio/wav'
};

// Synthesize speech, correct the wav header, then save to disk
// (wav header requires a file length, but this is unknown until after the header is already generated and sent)
textToSpeech
  .synthesize(params, function(err, audio) {
    if (err) {
      console.log(err);
      return;
    }
    textToSpeech.repairWavHeader(audio);
    fs.writeFileSync('audio.wav', audio);
    console.log('audio.wav written with a corrected wav header');
});
```

### Tone Analyzer

Use the [Tone Analyzer][tone_analyzer] service to analyze the
emotion, writing and social tones of a text.

```js
var ToneAnalyzerV3 = require('watson-developer-cloud/tone-analyzer/v3');

var toneAnalyzer = new ToneAnalyzerV3({
  username: '<username>',
  password: '<password>',
  version: '2016-05-19',
  url: 'https://gateway.watsonplatform.net/tone-analyzer/api/'
});

toneAnalyzer.tone(
  {
    tone_input: 'Greetings from Watson Developer Cloud!',
    content_type: 'text/plain'
  },
  function(err, tone) {
    if (err) {
      console.log(err);
    } else {
      console.log(JSON.stringify(tone, null, 2));
    }
  }
);
```


### Visual Recognition

Use the [Visual Recognition][visual_recognition] service to recognize the
following picture.

<img src="https://visual-recognition-demo.ng.bluemix.net/images/samples/5.jpg" />

```js
var VisualRecognitionV3 = require('watson-developer-cloud/visual-recognition/v3');
var fs = require('fs');

var visualRecognition = new VisualRecognitionV3({
  url: '<service_url>',
  version: '2018-03-19',
  iam_apikey: '<iam_api_key>',
});

var params = {
  images_file: fs.createReadStream('./resources/car.png')
};

visualRecognition.classify(params, function(err, res) {
  if (err) {
    console.log(err);
  } else {
    console.log(JSON.stringify(res, null, 2));
  }
});
```


## Composing services

### Integration of Tone Analyzer with Conversation
Sample code for [integrating Tone Analyzer and Conversation][conversation_tone_analyzer_example] is provided in the [examples directory][examples].

## Unauthenticated requests
By default, the library tries to use Basic Auth and will ask for `api_key` or `username` and `password` and send an `Authorization: Basic XXXXXXX`. You can avoid this by using:

`use_unauthenticated`.

```javascript
var watson = require('watson-developer-cloud');

var assistant = new watson.AssistantV1({
  use_unauthenticated: true
});
```

## Debug

This library relies on the `request` npm module writted by
[request][request_github] to call the Watson Services. To debug the apps, add
'request' to the `NODE_DEBUG` environment variable:

```sh
$ NODE_DEBUG='request' node app.js
```
where `app.js` is your Node.js file.

## Tests
Running all the tests:
```sh
$ npm test
```

Running a specific test:
```sh
$ mocha -g '<test name>'
```

## Open source @ IBM
[Find more open source projects on the IBM Github Page.](http://ibm.github.io/)

## License

This library is licensed under Apache 2.0. Full license text is available in
[COPYING][license].

## Contributing

See [CONTRIBUTING](https://github.com/watson-developer-cloud/node-sdk/blob/master/.github/CONTRIBUTING.md).

[assistant]: https://www.ibm.com/watson/services/conversation/
[conversation]: https://www.ibm.com/watson/services/conversation/
[discovery]: https://www.ibm.com/watson/services/discovery/
[personality_insights]: https://www.ibm.com/watson/services/personality-insights/
[visual_recognition]: https://www.ibm.com/watson/services/visual-recognition/
[tone_analyzer]: https://www.ibm.com/watson/services/tone-analyzer/
[text_to_speech]: https://www.ibm.com/watson/services/text-to-speech/
[speech_to_text]: https://www.ibm.com/watson/services/speech-to-text/
[language_translator]: https://www.ibm.com/watson/services/language-translator/
[ibm_cloud]: https://console.bluemix.net
[watson-dashboard]: https://console.bluemix.net/dashboard/apps?category=watson
[npm_link]: https://www.npmjs.com/package/watson-developer-cloud
[request_github]: https://github.com/request/request
[dialog_migration]: https://console.bluemix.net/docs/services/conversation/index.html
[examples]: https://github.com/watson-developer-cloud/node-sdk/tree/master/examples
[document_conversion_integration_example]: https://github.com/watson-developer-cloud/node-sdk/tree/master/examples/document_conversion_integration.v1.js
[conversation_tone_analyzer_example]: https://github.com/watson-developer-cloud/node-sdk/tree/master/examples/conversation_tone_analyzer_integration
[license]: http://www.apache.org/licenses/LICENSE-2.0
[vcap_services]: https://console.bluemix.net/docs/services/watson/getting-started-variables.html
[ibm-cloud-onboarding]: http://console.bluemix.net/registration?target=/developer/watson&cm_sp=WatsonPlatform-WatsonServices-_-OnPageNavLink-IBMWatson_SDKs-_-Node

