Create a Basic Authentication Connector

🕐 5 min read

Use cases
Instructions

The basic authentication boilerplate is a connector that ingests Excel data and uses the built-in TACO Excel file parser from a basic authentication endpoint.

Use cases

Basic authentication
Custom authentication
Excel
Built-in Excel parser

Instructions

To create your basic authentication connector, we recommend that you first create a sample basic authentication connector and edit the generated files. It’s easier to get all the files and directory structure your connector needs by just using an existing example.

To create your basic authentication connector, do the following steps.

Step 1: Create a boilerplate basic authentication connector

Enter the following command to create the connector:
```
taco create my-basic-auth-connector --boilerplate basic-auth 
```
This creates a directory with the earthquake data boilerplate code, which is included with the toolkit.
Change directories to the my-basic-auth-connector directory.
```
cd my-basic-auth-connector
```
Build the connector by entering the following command:
```
taco build
```
This command clears any previous or existing build caches, then installs the dependencies, then builds the frontend code and the backend code (handlers), then copies the connector.json file (the configuration file).

Step 2: Configure your connector’s properties

In your new basic authentication connector directory, find and open the connector.json file.

{
  "name": "my-basic-auth-connector",
  "version": "1.0.0",
  "tableau-version": {
    "min": "2022.3"
  },
  "vendor": {
    "name": "vendor-name",
    "support-link": "https://vendor-name.com",
    "email": "support@vendor-name.com"
  },
  "permission": {
    "api": {
      "https://*.usgs.gov/": [
        "GET",
        "POST",
        "HEAD"
      ]
    }
  },
  "auth": {
    "type": "custom"
  },
  "window": {
    "height": 800,
    "width": 600
  }
}

Make the following changes:

Change the general properties.

Name	Value
name	Your connector’s directory name
displayName	Your connector’s name. This is the name that appears in the Tableau connectors area.
version	Your connector’s version
min	The earliest Tableau version your connector supports

Change the company properties.

Name	Value
vendor.name	Your company name
vendor.support-link	Your company’s URL
vendor.email	Your company’s email

Change the permissions.

Name	Value
permission.api	The URI for the API that the connector is allowed to access, along with the methods (POST, GET, PUT, PATCH, DELETE) that the connector is allowed to use.

Verify the authentication value.

Name Value

auth.type Set to custom

custom covers basic authentication (username and password) and custom authentication (API keys or tokens). For more information about authentication, see the Authentication section in the Considerations for Building Your Connector topic.

Name	Value
auth.type	Set to `custom`

Change the HTML pane size.

Name	Value
window.height	The height of the connector HTML pane
window.width	The width of the connector HTML pane

Step 3: Edit the user interface

When you open a web data connector in Tableau, the connector displays an HTML page that links to your JavaScript code and to your connector’s handlers. Optionally, this page can also display a user interface for your users to select the data that they want to download.

To create a user interface (UI) for your connector, open the /app/index.html file and make any edits for your connector.

<!DOCTYPE html>
<html>

<head>
  <title>Basic Auth Sample Connector</title>
  <meta http-equiv="Cache-Control" content="no-store" />
  <link rel="icon" href="data:,">
  <link href="index.css" rel="stylesheet" />
  <script src="index.ts" type="module" defer></script>
</head>

<body>
  <p id="error" style="display: block; margin-top: 2em; height: 5px; text-align: center; color: red;"></p>

  <div class="box m-auto ">
    <div class="card">
      <div class="card-header">
        Basic Auth Sample Connector
      </div>

      <div class="card-body">
        <label for="userName" class="form-label">User Name</label>
        <input type="text" id="username" class="form-control mb-3" placeholder="User Name">

        <label for="Password" class="form-label">Password</label>
        <input type="password" id="password" class="form-control mb-4" placeholder="Password">

        <div class=" text-center">
          <button type="button" class="btn btn-success" id="submitButton" disabled>
            Please wait while settings load...
          </button>
        </div>
      </div>

    </div>
  </div>

</body>

</html>

Some notes about what the code is doing:

The meta tag prevents your browser from caching the page.
The index.css file is used to simplify styling and formatting.
The index.ts file is the code for your connector.
The input type="text" is the form field for the username.
The input type="password" is the form field for the password.

Step 4: Edit the connector object

Now that you’ve created a user interface, it’s time to edit the JavaScript code for the connector’s button. The code is in the /app/index.js file.

The connector object is used to submit data from the connector UI to connector handlers.

const connector = new Connector(() => {
  connectorInitialized = true
  enableButtonWhenReady()
})

The following code shows how a connector sets variables (for example, secrets, handlerInputs) for the connector object before submitting.

 function submit() {
   const username = document.querySelector<HTMLInputElement>('#username')?.value
   const password = document.querySelector<HTMLInputElement>('#password')?.value
   if (!username || !password) {
     return
   }

   connector.secrets = { username, password }
   connector.handlerInputs = [
     {
       fetcher: 'DataFetcher',
       parser: 'taco:excel-file-parser',
       data: {},
       name: 'unique-workbook-name',
     },
   ]

   connector.submit()
 }

For more information about the Connector object, see Class Connector in the SDK documentation.

Step 5: Update the fetcher file

If your data is complex and needs preprocessing, use the TACO Toolkit library to prepare your data. The following is the default code in the handlers/DataFetcher.js file that gets the data:

import { Fetcher, FetchUtils, FetchOptions, getBasicAuthHeader } from '@tableau/taco-toolkit/handlers'

export default class DataFetcher extends Fetcher {
  async *fetch({ secrets }: FetchOptions) {
    const { username, password } = secrets
    const headers = getBasicAuthHeader(username, password)

    // PLACEHOLDER: the url is NOT real endpoint.
    // Replace the url with actual endpoint that supports basic auth for corresponding file type.
    // Note: the permission setting in connector.json also needs to be updated accordingly.
    const url = 'https://www.example.com/api/user'

    yield await FetchUtils.loadExcelData(url, { headers })
  }
}

For information about FetchUtils.loadExcelData, see loadExcelData

Step 6: Build your connector

Enter these commands to build, pack, and run your new connector:

taco build

taco pack

taco run Desktop