CassandraLens

Query, explore, and manage Apache Cassandra databases directly from Visual Studio Code.

⚠️ Early Access - Version 0.1.0: This is the initial public release with core functionality. We're actively developing new features and appreciate your feedback!

Overview

CassandraLens brings powerful Apache Cassandra database management capabilities to VS Code. Execute CQL queries, browse schemas, manage connections, and more—all without leaving your editor.

Perfect for:

Cassandra developers who live in VS Code
Database administrators managing Cassandra clusters
Data engineers working with CQL
Anyone who prefers keyboard-driven database tools

✨ Features

🚀 CQL Query Execution

Execute CQL queries with rich syntax highlighting and inline results.

Keyboard Shortcut: Ctrl+Enter (Windows/Linux) or Cmd+Enter (macOS)
Run All Queries: Execute entire file with ▶ Run All button
Per-Statement Execution: Click ▶ Run button on individual statements
Execution Time Tracking: See query performance metrics
Result Formats: View results in table or JSON format
Multi-Connection Support: Use @conn directive to target specific clusters

📊 Interactive Query Results

View and explore query results in a clean, tabular interface.

Pagination: Navigate large result sets with configurable page sizes (100/250/500 rows)
Column Metadata: See data types and column information
Copy-Friendly: Easy selection and copying of result data
Execution Metrics: View row counts and execution times

🗂️ Schema Explorer

Browse your Cassandra database structure in an intuitive tree view.

Keyspace Navigation: Expand keyspaces to view tables and user-defined types
Table Inspection: See all columns with data types and key designations
Quick Actions: Right-click for Browse Data, Describe Table, Copy Name operations
System Keyspace Filtering: Optionally hide system keyspaces
Schema Caching: Fast performance with intelligent caching
Refresh on Demand: Update schema view with a click

🔌 Connection Management

Save and manage multiple Cassandra cluster connections.

Multiple Connections: Save unlimited connection profiles
Secure Password Storage: Credentials stored in VS Code's secure storage
Quick Switching: Switch between clusters with Command Palette
Auto-Connect: Automatically reconnect to last-used cluster on startup
Connection Status: Visual indicators show active connections
Edit & Delete: Manage saved connections easily

⚡ IntelliSense & CodeLens

Smart code assistance for CQL queries.

Keyword Completion: Intelligent suggestions for CQL commands
Syntax Highlighting: Full CQL language support
CodeLens Buttons: Inline ▶ Run buttons in CQL files
Connection Indicators: See which cluster queries will execute against
Multi-Connection Warnings: Alerts when file uses multiple clusters

🎯 Advanced Features

@conn Directive: Target specific clusters per query

-- @conn Production-Cluster
SELECT * FROM users WHERE user_id = 123;

-- @conn Staging-Cluster
SELECT * FROM users WHERE user_id = 123;

Context Menu Actions: Right-click on schema items for:

Browse Table Data
Describe Table
Copy Names/Paths
Refresh Schema

Status Bar Integration: See connection status and query results at a glance

📦 Installation

From VS Code Marketplace

Open VS Code
Press Ctrl+Shift+X (Windows/Linux) or Cmd+Shift+X (macOS)
Search for "CassandraLens"
Click Install

From Command Line

code --install-extension gnana997.cassandra-lens

From VSIX File

Download the .vsix file from GitHub Releases
Open VS Code
Press Ctrl+Shift+P → Extensions: Install from VSIX...
Select the downloaded file

🚀 Quick Start

1. Add Your First Connection

Click the + icon in the CassandraLens sidebar
Or run command: CassandraLens: Add Connection

2. Configure Connection

Enter your cluster details:

Name: "My Cluster"
Contact Points: localhost (or your cluster IPs)
Port: 9042 (default CQL port)
Local Datacenter: datacenter1
Username/Password: (if authentication enabled)

3. Connect

Click Save to create the connection
Click Connect or right-click → Connect to Connection

4. Browse Schema

Expand your keyspace in the tree view
Explore tables and columns

5. Run Your First Query

Create a new .cql file or click New Query
Type your CQL query
Press Ctrl+Enter (Windows/Linux) or Cmd+Enter (macOS)
View results in the query results panel!

⚙️ Configuration

CassandraLens can be customized through VS Code settings. Access via:

File → Preferences → Settings → Search for "CassandraLens"
Or edit settings.json directly

Available Settings

Setting	Type	Default	Description
`cassandraLens.connection.autoConnectOnStartup`	`boolean`	`true`	Automatically connect to the most recently used connection when VS Code starts
`cassandraLens.schema.filterSystemKeyspaces`	`boolean`	`false`	Hide system keyspaces (system, system_auth, etc.) in the schema tree
`cassandraLens.schema.cacheEnabled`	`boolean`	`true`	Enable caching of schema metadata to improve performance
`cassandraLens.query.defaultPageSize`	`number`	`100`	Default number of rows to display per page (100, 250, or 500)
`cassandraLens.query.completionMessageFormat`	`string`	`"detailed"`	Format of query completion messages: `"minimal"`, `"detailed"`, or `"verbose"`
`cassandraLens.query.completionMessageDuration`	`number`	`3000`	Duration (ms) to show completion messages in status bar (1000-10000)
`cassandraLens.editor.codeLensMode`	`string`	`"detailed"`	CodeLens display mode: `"off"`, `"minimal"`, `"standard"`, or `"detailed"`
`cassandraLens.editor.warnOnConnectionSwitch`	`boolean`	`true`	Show confirmation when @conn directive switches connections

Example Configuration

{
  "cassandraLens.connection.autoConnectOnStartup": true,
  "cassandraLens.query.defaultPageSize": 250,
  "cassandraLens.query.completionMessageFormat": "verbose",
  "cassandraLens.editor.codeLensMode": "detailed",
  "cassandraLens.schema.filterSystemKeyspaces": true
}

CodeLens Modes Explained

Off: No CodeLens buttons (use keyboard shortcuts only)
Minimal: ▶ Run All button and connection indicator at file top
Standard: Minimal + multi-connection warning
Detailed: All above + ▶ Run buttons on each statement (Recommended)

⌨️ Keyboard Shortcuts & Commands

Default Keyboard Shortcuts

Command	Windows/Linux	macOS	Description
Execute Query	`Ctrl+Enter`	`Cmd+Enter`	Run selected query or query at cursor

Available Commands

All commands are accessible via Command Palette (Ctrl+Shift+P / Cmd+Shift+P):

Connection Management:

CassandraLens: Add Connection - Create a new connection profile
CassandraLens: Connect - Connect to a saved cluster
CassandraLens: Switch Connection - Switch active connection
CassandraLens: Disconnect - Close current connection
CassandraLens: Edit Connection - Modify connection settings
CassandraLens: Delete Connection - Remove saved connection
CassandraLens: Refresh Connections - Reload connection list

Query Operations:

CassandraLens: Execute Query - Run current query (Ctrl+Enter)
CassandraLens: New Query - Create new CQL editor

Schema Operations:

CassandraLens: Browse Table Data - View table contents
CassandraLens: Describe Table - Show table structure
CassandraLens: Copy Keyspace Name - Copy to clipboard
CassandraLens: Copy Table Name - Copy to clipboard
CassandraLens: Copy Column Name - Copy to clipboard
CassandraLens: Copy Column Path - Copy qualified path
CassandraLens: Refresh - Refresh schema node

Customizing Shortcuts

You can customize keyboard shortcuts:

Open Command Palette (Ctrl+Shift+P / Cmd+Shift+P)
Type "Preferences: Open Keyboard Shortcuts"
Search for "CassandraLens"
Click the pencil icon to edit

📋 Requirements

Minimum Requirements

VS Code: Version 1.105.0 or higher
Cassandra: Apache Cassandra 3.x, 4.x, or DataStax Enterprise
Network: Access to Cassandra cluster on port 9042 (default)

Supported Cassandra Versions

Apache Cassandra 3.11.x
Apache Cassandra 4.0.x
Apache Cassandra 4.1.x
DataStax Enterprise 6.8.x
DataStax Astra (cloud-hosted Cassandra)

🎯 Current Status - Version 0.1.0

This is the initial public release of CassandraLens. Core features are stable and ready for daily use, but we're actively adding new functionality based on community feedback.

✅ What Works Now

✅ CQL query execution with syntax highlighting
✅ Schema browsing (keyspaces, tables, columns, types)
✅ Multiple saved connection profiles
✅ Secure credential storage
✅ Query results in table/JSON format
✅ CodeLens inline execution buttons
✅ @conn directive for multi-cluster workflows
✅ Context menu schema operations
✅ Auto-reconnect on startup
✅ Execution time tracking
✅ Query result export (CSV, JSON)

🚧 Known Limitations

Results limited to 500 rows per page
No query result export (CSV/JSON) yet
Limited support for complex UDTs (User-Defined Types)
No visual query builder
Schema operations (CREATE/ALTER/DROP) via CQL only

🔮 Roadmap - Coming Soon

We're actively working on these features for upcoming releases:

v0.2.0 (Next Release)

[ ] Enhanced error handling and suggestions
[ ] Query history and favorites
[ ] Table-level IntelliSense (column completion)
[ ] Performance improvements for large schemas

Future Releases

[ ] Visual schema designer (CREATE TABLE via UI)
[ ] Query builder with drag-and-drop
[ ] Import data from files (CSV, JSON)
[ ] Multi-cluster monitoring dashboard
[ ] Advanced UDT support
[ ] DataStax Astra one-click connect

Have a feature request? Open an issue - we'd love to hear from you!

🐛 Known Issues

Connection Issues

"All hosts unreachable" error

Ensure Cassandra cluster is running: nodetool status
Verify contact points and port in connection settings
Check firewall allows port 9042
Confirm local datacenter name matches your cluster

"Authentication failed" error

Double-check username and password
Ensure PasswordAuthenticator is enabled in cassandra.yaml
Try creating a new connection profile

Query Issues

"Timeout" errors

Increase cassandraLens.query.queryTimeout setting
Add LIMIT clause to large queries
Check cluster health and load

General Issues

Extension not activating

Check Output panel: View → Output → Select "CassandraLens"
Look for activation errors
Restart VS Code
Reinstall extension if needed

For other issues: Check GitHub Issues or open a new issue

🤝 Contributing

We welcome contributions! CassandraLens is open source and community-driven.

Ways to Contribute

Report Bugs: Open an issue with details
Request Features: Share your ideas in GitHub Issues
Submit Pull Requests: Fork, code, and submit PRs
Improve Documentation: Help make our docs better
Share Feedback: Let us know how you use CassandraLens!

Development Setup

# Clone repository
git clone https://github.com/gnana997/cassandra-lens.git
cd cassandra-lens

# Install dependencies
npm install

# Compile and watch for changes
npm run watch

# Run extension in Extension Development Host
Press F5 in VS Code

💬 Support & Feedback

Get Help

Issues: GitHub Issues
Discussions: GitHub Discussions
Documentation: This README and inline help

Feedback

We're constantly improving CassandraLens. Your feedback helps shape future releases!

⭐ Star the repo if you find it useful
📣 Share with other Cassandra developers
💡 Suggest features via GitHub Issues
🐛 Report bugs to help us improve

After using CassandraLens, you'll be prompted to share feedback after executing 10 queries. You can also manually share feedback anytime:

Command Palette: CassandraLens: Send Feedback
Choose from: Share Feedback, Report Bug, Request Feature, or View Documentation

Your feedback helps us prioritize features and improvements! All tracking is privacy-first—we never see your queries or connection details.

📄 License

This extension is licensed under the MIT License.

🙏 Acknowledgments

Built with cassandra-driver - DataStax Node.js driver for Apache Cassandra
Inspired by SQLTools and other excellent database extensions
Icon design inspired by Apache Cassandra logo

📊 Badges & Stats

Enjoying CassandraLens? Please consider leaving a review on the marketplace!

Made with ❤️ for the Cassandra community

Report Bug · Request Feature · View Roadmap

CassandraLens

Gnana997

CassandraLens

Overview

✨ Features

🚀 CQL Query Execution

📊 Interactive Query Results

🗂️ Schema Explorer

🔌 Connection Management

⚡ IntelliSense & CodeLens

🎯 Advanced Features

📦 Installation

From VS Code Marketplace

From Command Line

From VSIX File

🚀 Quick Start

1. Add Your First Connection

2. Configure Connection

3. Connect

4. Browse Schema

5. Run Your First Query

⚙️ Configuration

Available Settings

Example Configuration

CodeLens Modes Explained

⌨️ Keyboard Shortcuts & Commands

Default Keyboard Shortcuts

Available Commands

Customizing Shortcuts

📋 Requirements

Minimum Requirements

Supported Cassandra Versions

🎯 Current Status - Version 0.1.0

✅ What Works Now

🚧 Known Limitations

🔮 Roadmap - Coming Soon

🐛 Known Issues

Connection Issues

Query Issues

General Issues

🤝 Contributing

Ways to Contribute

Development Setup

💬 Support & Feedback

Get Help

Feedback

Share Your Experience

📄 License

🙏 Acknowledgments

📊 Badges & Stats