Spring Lens

Spring Lens is a developer observability and diagnostics tool for Spring Boot applications that provides deep visibility into your application's runtime behavior with zero application code changes. Inspired by Laravel Telescope, Spring Lens helps developers understand what happens inside their application by collecting and visualizing information about:

• Spring Beans
• HTTP Requests and Responses
• SQL Queries
• Method Executions
• Events
• Caches
• Scheduled Tasks
• Async Operations
• Application Startup

Simply add Spring Lens as a dependency and start exploring your application's internals.

Why Spring Lens?

Modern Spring Boot applications are highly dynamic and heavily rely on auto-configuration, proxies, asynchronous execution, and runtime infrastructure.

Understanding:

• why startup is slow,
• which beans depend on each other,
• which SQL queries were executed,
• how requests flow through your application,
• or where performance bottlenecks exist

often requires multiple tools, log analysis, and custom instrumentation.

Spring Lens aims to provide all of these insights in one place.

Features

Bean Explorer

Inspect your application's Spring container in real time.

Features include:

• Bean definitions
• Bean instances
• Initialization duration
• Scope information
• Dependency graph
• Lazy initialization visibility
• Factory methods
• Bean origin and resource location
• Proxy information
• Startup instance

HTTP Request Monitoring

Observe incoming HTTP traffic similar to Laravel Telescope's request watcher.

Captured information includes:

• HTTP method
• URI and query parameters
• Request headers
• Request body
• Response headers
• Response body
• Response status
• Execution duration
• Client IP address
• Correlated SQL executions

SQL Query Tracking

Monitor database activity generated during request processing.

Features:

• Executed SQL statements
• Execution duration
• Bound parameters
• Exception information
• Request correlation
• Slow query detection

Method Execution Monitoring

Track application method execution timings.

Features:

• Method name
• Class name
• Execution duration
• Exception information
• Request correlation
• Package filtering

Startup Diagnostics

Understand exactly how your application starts.

Features:

• Bean initialization instance
• Slow bean detection
• Startup bottleneck analysis
• Dependency chain visualization

Dependency Graph Visualization

Explore your Spring application as an interactive graph.

Visualize:

• Bean dependencies
• Bean dependents
• Circular dependencies
• Application architecture

Zero Configuration Philosophy

Spring Lens is designed around a simple principle:

Developers should not modify application code to gain observability.

No annotations.

No custom APIs.

No manual registration.

Simply add the dependency:

<dependency>
    <groupId>io.github.sdlc-pro</groupId>
    <artifactId>spring-lens-starter</artifactId>
    <version>1.0.0</version>
</dependency>

and Spring Lens automatically integrates with your application.

Architecture

Spring Lens consists of several independent modules:

spring-lens-core
spring-lens-insight
spring-lens-storage
spring-lens-exposure
spring-lens-ui
spring-lens-autoconfigure
spring-lens-starter

spring-lens-core

Provides shared abstractions and infrastructure:

• Repository API
• Pagination
• Filtering
• Sorting
• Shared contracts

spring-lens-insight

Responsible for runtime information collection:

• Bean observations
• HTTP observations
• SQL observations
• Method observations

spring-lens-storage

Persistence implementations for collected data.

Supported storage providers:

• In-memory
• Redis
• Custom implementations

spring-lens-exposure

Exposes collected data through:

• REST API
• Actuator endpoints
• CLI integration
• JMX support

spring-lens-ui

Default modern UI for insight visualization

spring-lens-autoconfigure

Connects modules together using Spring Boot auto-configuration.

spring-lens-starter

Convenient dependency for end users.

Supported Spring Versions

Spring Boot	Support
3.x	✅
2.x	Planned

Design Goals

Spring Lens is built around the following principles:

• Zero application code changes
• Production-safe defaults
• Low overhead
• Modular architecture
• Extensible storage model
• Framework-native integration
• Developer-first experience

Roadmap

Planned Features

• SQL query monitoring
• Cache monitoring
• Event monitoring
• Scheduler monitoring
• Async execution tracking
• Distributed tracing support
• And many more...

Comparison

Feature	Spring Lens	Spring Boot Actuator	Laravel Telescope
Bean Explorer	✅	❌	❌
Request Monitoring	✅	Partial	✅
SQL Monitoring	✅	❌	✅
Dependency Graph	✅	❌	❌
Startup Diagnostics	✅	Partial	❌
Zero Code Changes	✅	✅	✅

Philosophy

Spring Lens is not intended to replace:

• Spring Boot Actuator
• Micrometer
• OpenTelemetry
• Prometheus

Instead, Spring Lens focuses on one specific problem:

Giving developers a clear and intuitive understanding of what their Spring application is doing internally.

Contributing

Contributions, ideas, feature requests, and discussions are welcome.

If you have suggestions or would like to contribute, please open an issue or submit a pull request.

Inspiration

Spring Lens is heavily inspired by:

• Laravel Telescope
• Spring Boot Actuator
• OpenTelemetry
• Micrometer
• Spring Boot Admin

Status

Spring Lens is currently under active development.