BootUI

BootUI is a Spring Boot 4 starter that adds an embedded, local-only developer console to your application.

It is served by the host application at /bootui/, uses internal /bootui/api/** endpoints, and packages the browser UI into the starter so consuming applications do not need Node.js or npm.

Features

BootUI exposes these panels in the same order as the application menu. See the feature details guide for explanations and screenshots for every panel.

Feature	What it helps with
Overview	See runtime identity, versions, ports, active profiles, activation reason, and safety state.
Startup Timeline	Inspect Spring Boot startup steps and durations when startup data is available.
Memory	Review JVM heap, non-heap, memory pools, garbage collectors, and suggested JVM options.
Health	Explore the Actuator health tree and contributor details.
Metrics	Browse Micrometer meters, tags, measurements, and a local live chart for selected metrics.
Conditions	Understand why auto-configuration classes matched, did not match, or were unconditional.
Beans	Search Spring beans by name, type, scope, resource, dependency, and BootUI classification.
Mappings	Review HTTP routes, handlers, methods, patterns, and produces/consumes metadata.
Configuration	Inspect effective configuration values, metadata, masking, and local runtime overrides.
Profile Diff	Compare profile-specific property sources and values while preserving secret masking.
Loggers	Inspect and change logger levels at runtime through the Actuator loggers endpoint.
Log Tail	Read recent application logs and stream new local log events from the running process.
Traces	Inspect distributed tracing spans collected by the embedded OTLP receiver with a per-trace waterfall view.
AI Usage	Summarize Spring AI chat conversations, token usage, latency, and model details from OpenTelemetry spans.
HTTP Probe	Send local-only HTTP requests to the app and inspect response status, headers, and body.
DevTools	Check Spring Boot DevTools status, LiveReload availability, and restart controls.
Dev Services	Inspect Docker Compose snapshots, Testcontainers beans, service connection metadata, and bounded logs.
Scheduled Tasks	View registered scheduled tasks and their trigger metadata.
Data	Explore Spring Data repositories, domain types, IDs, and query methods.
Cache	Inspect Spring Cache managers, caches, metrics, annotations, and confirmed clear actions.
Security	Inspect Spring Security filter chains and best-effort endpoint rule explanations.
Vulnerabilities	Review dependency inventory and local OSV vulnerability scan results.

Some panels depend on optional Spring, Actuator, or development infrastructure. When data is unavailable, BootUI returns stable empty responses or shows an explanatory empty state. The sidebar also dims panels whose backing classpath or endpoint support is unavailable so you can spot empty sections immediately.

Setup

1) Prerequisites

• Java 25
• Spring Boot 4.x application
• Maven or your application's Maven Wrapper

2) Add the starter dependency

<dependency>
  <groupId>com.julien-dubois.bootui</groupId>
  <artifactId>bootui-spring-boot-starter</artifactId>
  <version>0.1.0-alpha.4</version>
</dependency>

3) Run your app in development mode

./mvnw spring-boot:run -Dspring-boot.run.profiles=dev

BootUI also activates automatically when spring-boot-devtools is on the classpath. To force it on or off:

bootui.enabled=AUTO
bootui.enabled=ON
bootui.enabled=OFF

prod and production profiles disable BootUI unless bootui.enabled=ON is set. Invalid bootui.enabled values fail closed and keep BootUI disabled.

4) Open BootUI

Visit: http://localhost:8080/bootui

Configuration and safety

BootUI is intended for local development only. By default it:

• activates in AUTO mode only for dev / local profiles or DevTools
• rejects non-loopback requests
• masks secret-like configuration values
• exposes the local Actuator endpoints used by BootUI panels when BootUI is active
• disables itself for prod / production profiles
• stores runtime configuration overrides in .bootui/application-bootui.properties, not in your source config files

Common properties:

Property	Default	Description
bootui.enabled	AUTO	AUTO, ON, or OFF.
bootui.enabled-profiles	dev,local	Profiles that activate BootUI in auto mode.
bootui.disabled-profiles	prod,production	Profiles that disable BootUI unless forced on.
bootui.allow-non-localhost	false	Explicit opt-out of loopback-only protection.
bootui.expose-values	MASKED	MASKED, METADATA_ONLY, or FULL; FULL can disclose secrets and should stay local.
bootui.overrides-file	.bootui/application-bootui.properties	Runtime override persistence file.
bootui.cache.clear-enabled	true	Enables Spring Cache clear actions after explicit browser confirmation.
bootui.dev-services.restart-enabled	false	Enables restart controls for bean-backed Testcontainers services. Disabled by default.
bootui.dev-services.log-tail-bytes	65536	Maximum bytes returned by one Dev Services log request.

Runtime overrides

The Configuration panel can create, update, and delete local runtime overrides. Overrides are stored in .bootui/application-bootui.properties by default, loaded at high precedence on the next startup, and never modify your application source configuration. Already-bound @ConfigurationProperties beans may keep their previous value until the app restarts; BootUI returns that warning with every override mutation.

Troubleshooting

Symptom	Check
/bootui returns 404	Use the dev or local profile, add DevTools, or set bootui.enabled=ON.
BootUI is disabled in prod	This is intentional; only bootui.enabled=ON can force activation with a disabled profile.
Browser is rejected	BootUI accepts loopback callers by default. Use bootui.allow-non-localhost=true only for a trusted local network.
A panel is empty	Enable the relevant Actuator endpoint or optional Spring module; BootUI degrades to stable empty DTOs when data is unavailable.
Startup Timeline is empty	Configure BufferingApplicationStartup in the host app.
Secrets are hidden	Default exposure is MASKED; use METADATA_ONLY to hide all values or FULL only in trusted local sessions.

Repository modules

• bootui-spring-boot-starter: dependency to add to your app
• bootui-autoconfigure: Spring Boot auto-configuration
• bootui-ui: Vue 3 frontend packaged into the starter
• bootui-core: shared DTOs and core helpers
• bootui-sample-app: demo and integration sample app

More docs

• Feature details: panel-by-panel guide with screenshots
• Sample app walkthrough: the demo app behind the screenshots and Playwright suite
• CHANGELOG.md: release notes
• CONTRIBUTING.md: contributor workflow, build, test, and publishing instructions
• SECURITY.md: threat model and security policy
• docs/SPECIFICATION.md: full product and technical specification
• docs/PLAN.md: implementation roadmap

License

Licensed under the Apache License, Version 2.0.