Integrating the CData JDBC Driver for Linear with Ignition SCADA

Ignition is an industrial supervisory control and data acquisition (SCADA) and industrial Internet of Things (IIoT) platform from Inductive Automation. Its central Gateway service manages device connections, tags, and database connections. Ignition doesn't ship with a connector for Linear, so reaching Linear data usually means custom middleware or manual exports.

The CData JDBC Driver for Linear bridges this gap by exposing Linear as a standard Java Database Connectivity (JDBC) data source. Ignition treats any JDBC driver as a standard database connection. Once the driver is registered in the Gateway, you can query live Linear data from the Script Console, SQL Bridge, tags, or a Perspective or Vision screen, without replication, custom connectors, or extract, transform, load (ETL) pipelines.

This guide outlines the steps to install and commission Ignition, register the CData JDBC Driver for Linear, create the connection, and verify it with a live query.

Prerequisites

• Ignition for Windows (Windows 10/11 or Windows Server), with administrator rights to install a Windows service
• CData JDBC Driver for Linear
• A Linear account with valid credentials and application programming interface (API) access enabled
• A supported desktop browser (Google Chrome, Mozilla Firefox, Microsoft Edge, or Safari) to open the Gateway web interface

Step 1: Install and set up Ignition

If Ignition is already installed and running, skip to Step 2.

Download Ignition

1. Go to the Inductive Automation downloads page and download Ignition for Windows.
2. This single download is the full Ignition Gateway installer. It includes both the Gateway service and the Designer Launcher, so you don't need a separate Designer download.

Install Ignition

1. Run the installer, accept the license agreement, and choose an install location.
2. Leave Install as a Windows Service checked so the Gateway starts with Windows.
3. Finish the installer. The Gateway service starts, and a browser window opens to http://localhost:8088 and shows the Commissioning wizard. If the page shows a Browser Not Supported notice, open the same address in Chrome, Firefox, Edge, or Safari.

Commission the Gateway

1. In the Commission Ignition Gateway wizard, set a Gateway Name and create an administrator username and password.
2. Accept the End User License Agreement, then start a trial or activate a purchased Ignition license.
3. When commissioning finishes, log in with the administrator account. You land on the Gateway Home page.

Note: A trial shows a countdown timer on every Gateway page, and the timer resets when the Gateway service restarts. This is fine for testing, but production use requires a license.

Step 2: Register the CData JDBC Driver in Ignition

Ignition lets you upload any third-party JDBC driver through the Gateway web interface, without touching the file system directly.

1. Log in to the Gateway as an administrator.
2. Go to Connections > Databases > Settings, open the Drivers tab, and click Create JDBC Driver.
3. In the dialog, enter the following:
   • Name: Linear
   • Classname: cdata.jdbc.linear.LinearDriver
   • Driver Type: Generic
   • Default Validation Query: SELECT id FROM Team LIMIT 1
   
4. Click Create JDBC Driver. In current Ignition 8.3 releases, the create dialog doesn't include a Java archive (JAR) file upload field, so you add the JAR file in the next step.
5. Open the menu at the right of the new driver row, choose Manage JAR files, upload cdata.jdbc.linear.jar from the lib folder of the driver installation, and save.
6. Confirm the driver shows an INSTALLED status in the drivers list.

Step 3: Create the Linear connection

1. Go to Connections > Databases > Connections and click Create Database Connection.
2. On the Driver Selection step, select Linear and click Next.
3. On the Database Setup step, set the Name to Linear. Leave Username empty and select None for Password, because the credentials go in the connect URL.
4. In Connect URL, enter the connection string:

   jdbc:linear:AuthScheme=APIKey;APIKey=myAPIKey;

   
5. Click Create Database Connection and confirm the connection shows a VALID status on the Database Connections page.

Connection properties for Linear

You can authenticate to Linear with a personal API key or with OAuth 2.0. The API key is the simplest option for connecting with your own Linear account.

Authenticating with an API Key

Set the following connection properties:

• AuthScheme: Set this to APIKey.
• APIKey: A Linear personal API key.

To create a personal API key, log in to Linear, open Settings > Security & access > Personal API keys, select New API key, and create it. Copy the key immediately, because Linear shows it only once.

Authenticating with OAuth

OAuth requires a custom OAuth application registered in Linear (Settings > API > OAuth applications), which provides the OAuthClientId and OAuthClientSecret. Two flows are supported:

• Authorization code: Set AuthScheme to OAuth, InitiateOAuth to GETANDREFRESH, and provide OAuthClientId, OAuthClientSecret, and the CallbackURL defined in your application (e.g., http://localhost:33333). The driver opens Linear in your browser so you can grant access.
• Client credentials: Set AuthScheme to OAuthClient and provide OAuthClientId and OAuthClientSecret. This authenticates the application itself, with no browser interaction, and suits machine-to-machine integrations.

By default, the driver requests the read,write scopes. The driver refreshes the access token automatically when it expires.

Note: If a password or token contains a semicolon, the connect URL breaks, so reset it to a value without one.

Step 4: Query live Linear data from Ignition

With the connection valid, you can query live Linear data from the Designer.

1. Open the Ignition Designer Launcher, select your Gateway (click Add Designer and enter http://localhost:8088 if it isn't listed), and click Open Designer. Log in with the Gateway administrator account.
2. Open or create a project. The Designer opens with the Project Browser, Tag Browser, and Component Palette panels.
3. In the Designer, go to Tools > Script Console. In the Multiline Buffer, enter a test query and click Execute. Replace Team with any table available in your Linear connection:

   print system.db.runQuery(
       "SELECT id, name FROM Team LIMIT 10",
       "Linear")

   
4. A successful query prints PyDataset rows:10 cols:2 in the Interactive Interpreter panel, which confirms Ignition retrieved live data from Linear through the CData JDBC Driver.

Note: The connection name in the script must match the name you gave the connection in Step 3.

Step 5: Verify the results

1. Print the rows and compare the values with the same records in Linear:

   ds = system.db.runQuery("SELECT id, name FROM Team LIMIT 10", "Linear")
   for row in ds:
       print row["id"], row["name"]

2. Optionally, run a second query against another table and a filtered query to confirm schema discovery and filtering.
3. Optionally, restart the Gateway service and confirm the connection returns to VALID.

Troubleshooting

Test the driver outside Ignition

To confirm the driver works independently of the Gateway, run this standalone Java example. The cdata.jdbc.linear.jar and cdata.jdbc.linear.lic files must be in the same directory and on the classpath.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class CDataExample {
    public static void main(String[] args) throws Exception {
        Class.forName("cdata.jdbc.linear.LinearDriver");
        String connectionString = "jdbc:linear:AuthScheme=APIKey;APIKey=myAPIKey;";
        try (Connection conn = DriverManager.getConnection(connectionString)) {
            Statement stmt = conn.createStatement();
            ResultSet rs = stmt.executeQuery("SELECT id, name FROM Team LIMIT 10");
            while (rs.next()) {
                System.out.println(rs.getString("id") + ", " + rs.getString("name"));
            }
        }
    }
}

Build live, governed Linear connectivity in Ignition with CData

With the CData JDBC Driver for Linear registered, your team can query live Linear data from Ignition without ETL infrastructure, manual exports, or custom integration code, and reuse the same connection in tags, SQL Bridge, and Perspective or Vision screens.

Start your free trial today to see how you can give Ignition live, secure access to hundreds of external systems with CData.