Intermediate tutorial: Creating HTTP requests from Web services

In this tutorial you will create a Web service driver that retrieves weather information from the OpenWeatherMap API.


Before you begin, it is recommended that you complete the Beginner tutorial.

Download and install the following tools:

You will then need to get an OpenWeatherMap API key by creating an account at and visiting the My API Keys section.


  1. Create a directory for the project by running the following commands:

    mkdir weather
    cd weather
    npm init --yes
  2. Add a kibana section to the package.json file as follows:

      "name": "weather",
      "version": "1.0.0",
      "description": "",
      "main": "index.js",
      "scripts": {
        "test": "echo \"Error: no test specified\" && exit 1"
      "author": "",
      "license": "ISC",
      "kibana": {
        "version": "5.6.10"
  3. Add the web-service-interface package by running the following command:

    npm install @sirensolutions/web-service-interface
  4. Add the axios package by running the following command:

    npm install axios
  5. Create a subdirectory to hold the source code of the driver:

    mkdir src
  6. Consider what you would like your input and output to look like. To get a response from OpenWeatherMap, you must supply two items in the request:

    • The name of a city

    • An API key

      You can then extract the fields you are interested in processing in Siren Investigate from the response.

  7. Create the file src/MyWeatherService.js with the following contents:

    "use strict"
    import { ServiceDefinition, WebServiceError } from '@sirensolutions/web-service-interface';
    import axios from 'axios';
    export class MyWeatherService extends ServiceDefinition { (1)
      name = 'weatherservice';
      inputSchema = {
        city_name: {
          type: 'text',
          description: 'name of the city to get weather information for',
          required: true
      outputConfiguration = { (2)
        weather: {
            name: 'keyword',
            main: 'text',
            location: 'geo_point',
            temperature: 'long'
      // Called to invoke the service. The inputs argument will have fields described in this.inputSchema
      async invoke(inputs) { (3)
        // The API endpoint to send a query to
        const url = '';
        // Parameters are added to the end of a URL:
        // E.g.<your-api-key>
        const params = {
          q: inputs.city_name,
          appid: '<your-api-key>' (4)
        const headers = {
          'Content-Type': 'application/json'
        // The axios library is used here, but you can use a different library/implementation for querying an API
        const response = await axios.get(url, { params, headers })
          .catch(error => Promise.reject(error.response && error.response.status < 500 ? new WebServiceError( : error)); (5)
        // Must return objects with the same structure as in this.outputConfiguration. These are stored in Elasticsearch automatically.
        return {
          weather: [{
    1 You need to export the class so that you can import it later in the index.js file.
    2 The outputConfiguration used here specifies that the objects be stored in dedicated indices: web-services-example-web-service-group-MyWeatherService-results-weather. For more information, see the Storing in dedicated data indices section of the Output configuration topic.
    3 The invoke function uses the async flag, which allows you to await the response from OpenWeatherMap. This saves you from having to write out a chain of callback handlers. The invoke function queries the OpenWeatherMap API with the city and the API key.
    4 Make sure to replace <your-api-key> with your API key.
    5 Here, you catch any errors if they should occur. There are two types of error that you can expect: a WebServiceError, which indicates invalid input or configuration, and any generic error which indicates a fault with the code or the external API. For more information, see Error handling
  8. Create a file named index.js with the following contents:

    "use strict";
    import { registerServices } from '@sirensolutions/web-service-interface';
    import { MyWeatherService } from './src/MyWeatherService'; (1)
    export default registerServices('weather', [MyWeatherService]);
    1 You import the weather Web service into the index.js file, so that you can register it to a Web service group named weather in the next line.
  9. It’s ready to go! Copy the whole project directory to the plugins folder in Siren Investigate by running the following command:

    cp -r . path/to/investigate/plugins/weather
  10. Start Elasticsearch by running the following commands:

    cd path/to/elasticsearch
  11. Go the directory where Siren Investigate has been installed:

    cd path/to/investigate
  12. Open the config/investigate.yml file and add the following snippet to enable Web services if it is not present:

        enabled: true
  13. Start Siren Investigate by running the following command:

  14. Open Siren Investigate in your browser (running on http://localhost:5606 by default), and click on the Web services dashboard.

    Web services dashboard

  15. Select weather openweathermap as the active Web service profile in the Query Web services visualization and click Save.

    The Query Web services visualization

  16. Enter a string in the message field and click Query; you should see the result of your request in the Invocation Results visualization.

    The result of the invocation

Next steps