Create Apps from HDFS Data in Qlik Sense Cloud

Qlik Sense Cloud allows you to create and share data visualizations and interact with information in new ways. The CData Connect Server creates a virtual database for HDFS and can be used to generate an OData API (natively consumable in Qlik Sense Cloud) for HDFS. By pairing Qlik Sense Cloud with the CData Connect Server, you get live connectivity to all of your SaaS and cloud-based Big Data and NoSQL sources — no need to migrate your data or write your integrations. Simply connect to Connect Server from Qlik Sense Cloud as you would any other REST service and get instant, live access to your HDFS data.

In this article, we walk through two connections:

1. Connecting to HDFS in Connect Server
2. Connecting to Connect Server from Qlik Sense Cloud to create a model and build a simple dashboard

Configure Connect Server to Connect to HDFS

To connect to HDFS data from Qlik Sense Cloud, you need to configure HDFS access from your Connect Server instance. This means creating a user, connecting to HDFS, adding OData endpoints, and (optionally) configuring CORS.

Add a Connect Server User

Create a Connect Server User to connect to HDFS from Qlik Sense Cloud.

1. Click Users -> Add
2. Configure a User
3. Click Save Changes and make note of the Authtoken for the new user

Connect to HDFS from Connect Server

CData Connect Server uses a straightforward, point-and-click interface to connect to data sources and generate APIs.

1. Open Connect Server and click Connections
2. Select "HDFS" from Available Data Sources
3. Enter the necessary authentication properties to connect to HDFS.
   
   

   In order to authenticate, set the following connection properties:

   • Host: Set this value to the host of your HDFS installation.
   • Port: Set this value to the port of your HDFS installation. Default port: 50070
4. Click Save Changes
5. Click Privileges -> Add, and add the new user (or an existing user) with the appropriate permissions (SELECT is all that is required for Reveal)

Add HDFS OData Endpoints in Connect Server

After connecting to HDFS, create OData Endpoint for the desired table(s).

1. Click OData -> Tables -> Add Tables
2. Select the HDFS database
3. Select the table(s) you wish to work with and click Next
4. (Optional) Edit the resource to select specific fields and more
5. Save the settings

(Optional) Configure Cross-Origin Resource Sharing (CORS)

When accessing and connecting to multiple domains from an application such as Ajax, there is a possibility of violating the limitations of cross-site scripting. In that case, configure the CORS settings in OData -> Settings.

• Enable cross-origin resource sharing (CORS): ON
• Allow all domains without '*': ON
• Access-Control-Allow-Methods: GET, PUT, POST, OPTIONS
• Access-Control-Allow-Headers: Authorization

Save the changes to the settings.

Create a Qlik Sense App from HDFS Data

With the connection to HDFS and OData endpoints created, we are ready to add HDFS data to a Qlik Sense app for visualizations, analytics, reporting, and more.

Create a New App and Upload Data

1. Log into your Qlik Sense instance and click the button to create a new app
2. Name and configure the new app and click "Create"
3. In the workspace, click to open the new app
4. Click to add data from files and other sources
5. Select the REST connector and set the configuration properties. For the most part, you will use the default values, with the following exceptions:
   • URL: Set this to the API endpoint for your HDFS table, using the @CSV URL parameter to ensure a CSV response (i.e. CONNECT_SERVER_URL/api.rsc/HDFS_Files?@CSV)
   • Authentication Schema: Set this to "Basic"
   • User Name: Set this to the user name you configured above
   • Password: Set this to the Authtoken for the above user
6. Click "Create" to query Connect Server for the HDFS data
7. Check "CSV has header" and under "Tables," select "CSV_source"
8. Select columns and click "Add data"

Generate Insights or Customize Your App

With the data loaded into Qlik Sense, you are ready to begin discovering insights. Click "Generate insights" to let Qlik analyze your data. Otherwise, you can build custom visualizations, reports, and dashboards based on your HDFS data.

More Information & Free Trial

Now, you have created a simple but powerful dashboard from live HDFS data. For more information on creating OData feeds from HDFS (and more than 200 other data sources), visit the Connect Server page. Sign up for a free trial and start working with live HDFS data in Qlik Sense Cloud.