How to Access Live Google Spanner Data in Visual Studio Code via Cline

Cline is an autonomous coding agent right in your IDE, capable of creating/editing files, running commands, using the browser, and more with your permission every step of the way. When paired with CData Code Assist MCP for Google Spanner, you get live access to CRM data within your IDE, enabling you to build, test, and validate data-driven features using real-time schema and records without ever leaving your development environment.

CData Code Assist MCP provides schema-aware context to AI tools — whether you're using it for AI-assisted code generation in IDEs like Cursor and Cline, or for querying live data through chat interfaces like Claude Desktop.

This article outlines how to run CData Code Assist MCP for Google Spanner on WSL (Windows Subsystem for Linux) and connect to it from the Cline extension in Visual Studio Code on Windows.

Background

Code Assist MCP is typically designed for clients like Claude Desktop. However, when attempting to use it via the Cline extension in Windows VS Code, the following error occurred:

MCP error -32000: Connection closed

This issue is suspected to be caused by I/O handling problems in the stdio transport implementation on the Windows version of the Cline extension.

• Related GitHub Issue: https://github.com/cline/cline/issues/3464
• Additionally, environment variables such as PATH may not be inherited correctly when launching processes like Java or Node.

Prerequisites

• Visual Studio Code installed on Windows
• Cline extension installed and configured in VS Code
• Windows Subsystem for Linux (WSL) installed with a working Linux distribution (e.g., Ubuntu)
• Java 21+ JRE installed in WSL
• CData Code Assist MCP for Google Spanner installed on Windows

Step 1: Authenticate with Google Spanner (on Windows)

Before running Code Assist MCP in WSL, you must complete authentication flow in a Windows environment. This ensures all necessary credentials are generated and stored properly. Find and run "CData Code Assist MCP for Google Spanner" or execute the JAR file to open the configuration wizard.

java -jar "C:\Program Files\CData\CData Code Assist MCP for Google Spanner 20XX\lib\cdata.mcp.googlespanner.jar"

Connecting to Google Spanner

Google Spanner uses the OAuth authentication standard. To authenticate using OAuth, you can use the embedded credentials or register an app with Google.

See the Getting Started guide in the CData driver documentation for more information.

Configuring Code Assist MCP

Name your configuration (e.g. cdatagooglespanner), enter the required connection properties, and click "Connect."

👁 The Code Assist MCP configuration wizard (Google Sheets is shown).

Upon successful connection, the following directory and files will be created:

C:\Users\<username>\AppData\Roaming\CData\googlespanner Provider\
 |-- cdatagooglespanner.mcp
 |-- (other supporting config files)

Step 2: Copy the Code Assist MCP Configuration into WSL

Next, copy the entire configuration folder from Windows into your WSL environment.

mkdir -p ~/.config/CData/
cp -r /mnt/c/Users/<username>/AppData/Roaming/CData/"googlespanner Provider" ~/.config/CData/

Ensure the destination path matches exactly: ~/.config/CData/googlespanner Provider/.

Step 3: Install Code Assist MCP on WSL

Install Java and place the Code Assist MCP JAR in the desired location within WSL:

sudo apt update
sudo apt install openjdk-21-jre-headless
sudo mkdir -p /opt/cdata/mcp_googlespanner/lib
sudo cp /mnt/c/Program\ Files/CData/CData\ Code\ Assist\ MCP\ for\ Google Spanner\ 20XX/lib/cdata.mcp.googlespanner.jar /opt/cdata/mcp_googlespanner/lib/

Step 4: Configure Cline

Now, configure the Cline extension to launch Code Assist MCP inside WSL using the wsl command.

Create or update cline_mcp_settings.json with the following content:

{
 "mcpServers": {
 "cdatagooglespanner": {
 "autoApprove": ["*"],
 "disabled": false,
 "timeout": 60,
 "type": "stdio",
 "command": "wsl",
 "args": [
 "-d",
 "Ubuntu", // Replace with your installed WSL distro name
 "--",
 "/usr/bin/java",
 "-jar",
 "/opt/cdata/mcp_googlespanner/lib/cdata.mcp.googlespanner.jar",
 "cdatagooglespanner"
 ],
 "env": {
 "JAVA_TOOL_OPTIONS": "-Xmx2g"
 }
 }
 }
}

Note: Replace Ubuntu with your actual WSL distribution name (e.g., Ubuntu-22.04). Run wsl -l in PowerShell or CMD to confirm.

Step 5: Interact with Live Data in Cline

From within Visual Studio Code, you can now run MCP commands through the Cline extension.

cdatagooglespanner_get_tables
cdatagooglespanner_get_columns Customer

If configured correctly, these commands will return a list of available Google Spanner objects and metadata, allowing you to interact with your CRM schema in real time.

Try natural language prompts like:

• "Generate a React form to create a new Google Spanner Lead."
• "Write a Python function to pull Opportunities closed this quarter."

Build with Code Assist MCP. Deploy with CData Drivers.

Download Code Assist MCP for free and give your AI tools schema-aware access to live Google Spanner data during development. When you're ready to move to production, CData Google Spanner Drivers deliver the same SQL-based access with enterprise-grade performance, security, and reliability.

Visit the CData Community to share insights, ask questions, and explore what's possible with MCP-powered AI workflows.