@ -333,6 +333,8 @@ To improve the user experience and further assist the user in configuring a give
* Associates a provider, to attach a well defined semantic to a property, so that a tool can discover the list of potential values based on the project's context.
The `name` attribute of each hint refers to the `name` of a property.
In the <<configuration-metadata-format,initial example shown earlier>>, we provide five values for the `spring.jpa.hibernate.ddl-auto` property: `none`, `validate`, `update`, `create`, and `create-drop`.
@ -378,6 +380,7 @@ If your IDE supports it, this is by far the most effective approach to auto-comp
The **handle-as** provider lets you substitute the type of the property to a more high-level type.
This typically happens when the property has a `java.lang.String` type, because you do not want your configuration classes to rely on classes that may not be on the classpath.
@ -545,6 +553,7 @@ It is actually used internally as a `org.springframework.core.io.Resource` but c
@ -20,6 +20,7 @@ Please refer to the plugin's documentation to learn more:
* {spring-boot-maven-plugin-api}[API]
[[build-tool-plugins-gradle-plugin]]
== Spring Boot Gradle Plugin
The Spring Boot Gradle Plugin provides Spring Boot support in Gradle, letting you package executable jar or war archives, run Spring Boot applications, and use the dependency management provided by `spring-boot-dependencies`.
@ -103,7 +104,6 @@ The following nested elements can be used with the task:
@ -290,12 +290,14 @@ In this document, we describe to approach using AWS Elastic Beanstalk.
[[cloud-deployment-aws-beanstalk]]
==== AWS Elastic Beanstalk
As described in the official https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/create_deploy_Java.html[Elastic Beanstalk Java guide], there are two main options to deploy a Java application.
You can either use the "`Tomcat Platform`" or the "`Java SE platform`".
[[cloud-deployment-aws-tomcat-platform]]
===== Using the Tomcat Platform
This option applies to Spring Boot projects that produce a war file.
No special configuration is required.
@ -303,6 +305,7 @@ You need only follow the official guide.
[[cloud-deployment-aws-java-se-platform]]
===== Using the Java SE Platform
This option applies to Spring Boot projects that produce a jar file and run an embedded web container.
Elastic Beanstalk environments run an nginx instance on port 80 to proxy the actual application, running on port 5000.
@ -344,6 +347,7 @@ You can also create single instance environments by using the CLI and the follow
[[cloud-deployment-aws-summary]]
==== Summary
This is one of the easiest ways to get to AWS, but there are more things to cover, such as how to integrate Elastic Beanstalk into any CI / CD tool, use the Elastic Beanstalk Maven plugin instead of the CLI, and others.
There is a https://exampledriven.wordpress.com/2017/01/09/spring-boot-aws-elastic-beanstalk-example/[blog post] covering these topics more in detail.
@ -62,6 +62,7 @@ If you are getting started with Spring Boot or 'Spring' in general, start with <
[[boot-documentation-workingwith]]
== Working with Spring Boot
Ready to actually start using Spring Boot? <<using-spring-boot.adoc#using-boot, We have you covered>>:
@ -73,6 +74,7 @@ Ready to actually start using Spring Boot? <<using-spring-boot.adoc#using-boot,
[[boot-documentation-learning]]
== Learning About Spring Boot Features
Need more details about Spring Boot's core features?
<<spring-boot-features.adoc#boot-features, The following content is for you>>:
@ -86,6 +88,7 @@ Need more details about Spring Boot's core features?
[[boot-documentation-production]]
== Moving to Production
When you are ready to push your Spring Boot application to production, we have <<production-ready-features.adoc#production-ready, some tricks>> that you might like:
@ -95,6 +98,7 @@ When you are ready to push your Spring Boot application to production, we have <
[[boot-documentation-advanced]]
== Advanced Topics
Finally, we have a few topics for more advanced users:
@ -597,7 +597,7 @@ You can enable HTTP/2 support in your Spring Boot application with the configpro
Both `h2` (HTTP/2 over TLS) and `h2c` (HTTP/2 over TCP) are supported.
To use `h2`, SSL must also be enabled.
When SSL is not enabled, `h2c` will be used.
The details of the `h2` support depend on the chosen web server and the application environment, since that protocol is not supported out-of-the-box by all JDK 8 releases.
The details of the `h2` support depend on the chosen web server and the application environment, since that protocol is not supported out-of-the-box by all JDK 8 releases.
@ -620,6 +620,7 @@ Starting Tomcat 9.0.x on JDK 8 with HTTP/2 and SSL enabled but without that nati
This error is not fatal, and the application still starts with HTTP/1.1 SSL support.
[[howto-configure-http2-jetty]]
==== HTTP/2 with Jetty
For HTTP/2 support, Jetty requires the additional `org.eclipse.jetty.http2:http2-server` dependency.
@ -1271,6 +1272,8 @@ The following example configures `HttpComponentsClientRequestFactory` with an `H
=== Configure the TcpClient used by a Reactor Netty-based WebClient
When Reactor Netty is on the classpath a Reactor Netty-based `WebClient` is auto-configured.
@ -1286,6 +1289,7 @@ TIP: Note the use of `ReactorResourceFactory` for the connection provider and ev
This ensures efficient sharing of resources for the server receiving requests and the client making requests.
[[howto-logging]]
== Logging
Spring Boot has no mandatory logging dependency, except for the Commons Logging API, which is typically provided by Spring Framework's `spring-jcl` module.
@ -1868,6 +1872,7 @@ Spring Boot provides properties in the `spring.data.web` namespace for customizi
Note that if you are using Spring Data REST, you must use the properties in the `spring.data.rest` namespace instead.
=== Expose Spring Data Repositories as REST Endpoint
Spring Data REST can expose the `Repository` implementations as REST endpoints for you,
@ -2309,6 +2314,7 @@ For more about Spring Security, see the {spring-security}[Spring Security projec
If you define a `@Configuration` with a `WebSecurityConfigurerAdapter` or a `SecurityFilterChain` bean in your application, it switches off the default webapp security settings in Spring Boot.
=== Change the UserDetailsService and Add User Accounts
If you provide a `@Bean` of type `AuthenticationManager`, `AuthenticationProvider`, or `UserDetailsService`, the default `@Bean` for `InMemoryUserDetailsManager` is not created.
@ -693,6 +693,7 @@ If no `HealthIndicator` returns a status that is known to the `StatusAggregator`
TIP: The `HealthContributorRegistry` can be used to register and unregister health indicators at runtime.
[[production-ready-health-indicators]]
==== Auto-configured HealthIndicators
The following `HealthIndicators` are auto-configured by Spring Boot when appropriate.
@ -787,6 +788,7 @@ Additional `HealthIndicators` are available but not enabled by default:
[[production-ready-health-indicators-writing]]
==== Writing Custom HealthIndicators
To provide custom health information, you can register Spring beans that implement the {spring-boot-actuator-module-code}/health/HealthIndicator.java[`HealthIndicator`] interface.
You need to provide an implementation of the `health()` method and return a `Health` response.
@ -905,6 +907,7 @@ TIP: To handle the error automatically, consider extending from `AbstractReactiv
[[reactive-health-indicators-autoconfigured]]
==== Auto-configured ReactiveHealthIndicators
The following `ReactiveHealthIndicators` are auto-configured by Spring Boot when appropriate:
@ -935,6 +938,7 @@ TIP: If necessary, reactive indicators replace the regular ones.
Also, any `HealthIndicator` that is not handled explicitly is wrapped automatically.
[[production-ready-health-groups]]
==== Health Groups
It's sometimes useful to organize health indicators into groups that can be used for different purposes.
@ -2324,6 +2328,7 @@ There are convenience static functions in `RestTemplateExchangeTags` and `WebCli
[[production-ready-metrics-tomcat]]
==== Tomcat Metrics
Auto-configuration will enable the instrumentation of Tomcat only when an `MBeanRegistry` is enabled.
By default, the `MBeanRegistry` is disabled, but you can enable it by setting configprop:server.tomcat.mbeanregistry.enabled[] to `true`.
@ -2425,7 +2430,6 @@ Auto-configuration will enable the instrumentation of all available RabbitMQ con
[[production-ready-metrics-integration]]
==== Spring Integration Metrics
Spring Integration provides {spring-integration-docs}system-management.html#micrometer-integration[Micrometer support] automatically whenever a `MeterRegistry` bean is available.
@ -2615,7 +2619,7 @@ NOTE: By default, metrics from all `MeterBinder` beans will be automatically bou
[[production-ready-metrics-per-meter-properties]]
[[production-ready-metrics-customizing]]
=== Customizing Individual Metrics
If you need to apply customizations to specific `Meter` instances you can use the `io.micrometer.core.instrument.config.MeterFilter` interface.
@ -2653,6 +2657,7 @@ As the order of common tags cannot be guaranteed using this approach, Graphite u
[[production-ready-metrics-per-meter-properties]]
==== Per-meter Properties
In addition to `MeterFilter` beans, it's also possible to apply a limited set of customization on a per-meter basis using properties.
Per-meter customizations apply to any all meter IDs that start with the given name.
@ -2835,6 +2840,7 @@ If your Cloud Foundry UAA or Cloud Controller services use self-signed certifica
[[production-ready-custom-context-path]]
=== Custom Context Path
If the server's context-path has been configured to anything other than `/`, the Cloud Foundry endpoints will not be available at the root of the application.
For example, if `server.servlet.context-path=/app`, Cloud Foundry endpoints will be available at `/app/cloudfoundryapplication/*`.
@ -53,6 +53,7 @@ This will also turn off logging of the application's active profiles.
TIP: To add additional logging during startup, you can override `logStartupInfo(boolean)` in a subclass of `SpringApplication`.
[[boot-features-startup-failure]]
=== Startup Failure
If your application fails to start, registered `FailureAnalyzers` get a chance to provide a dedicated error message and a concrete action to fix the problem.
@ -428,6 +429,8 @@ Spring Boot ships with the `BufferingApplicationStartup` variant; this implement
Applications can ask for the bean of type `BufferingApplicationStartup` in any component.
Additionally, Spring Boot Actuator will {spring-boot-actuator-restapi-docs}/#startup[expose a `startup` endpoint to expose this information as a JSON document].
[[boot-features-external-config]]
== Externalized Configuration
Spring Boot lets you externalize your configuration so that you can work with the same application code in different environments.
@ -714,6 +717,7 @@ If you want to support your own locations, see the `ConfigDataLocationResolver`
YAML documents need to be converted from their hierarchical format to a flat structure that can be used with the Spring `Environment`.
For example, consider the following YAML document:
@ -1633,6 +1640,7 @@ See the `setAdditionalProfiles()` method in {spring-boot-module-api}/SpringAppli
Profile groups, which are described in the <<boot-features-profiles-groups,next section>> can also be used to add active profiles if a given profile is active.
[[boot-features-profiles-groups]]
=== Profile Groups
Occasionally the profiles that you define and use in your application are too fine-grained and become cumbersome to use.
@ -1688,6 +1696,7 @@ TIP: When you deploy your application to a servlet container or application serv
This prevents logging performed by the container or other applications that have been deployed to it from appearing in your application's logs.
[[boot-features-logging-format]]
=== Log Format
The default log output from Spring Boot resembles the following example:
@ -2102,6 +2111,7 @@ If you attempt to do so, making changes to the configuration file results in an
The `<springProfile>` tag lets you optionally include or exclude sections of configuration based on the active Spring profiles.
Profile sections are supported anywhere within the `<configuration>` element.
@ -2128,6 +2138,7 @@ The following listing shows three sample profiles:
[[boot-features-logback-environment-properties]]
==== Environment Properties
The `<springProperty>` tag lets you expose properties from the Spring `Environment` for use within Logback.
Doing so can be useful if you want to access values from your `application.properties` file in your Logback configuration.
@ -2411,6 +2422,8 @@ See {spring-boot-autoconfigure-module-code}/web/ResourceProperties.java[`Resourc
This feature has been thoroughly described in a dedicated https://spring.io/blog/2014/07/24/spring-framework-4-1-handling-static-web-resources[blog post] and in Spring Framework's {spring-framework-docs}/web.html#mvc-config-static-resources[reference documentation].
====
[[boot-features-spring-mvc-welcome-page]]
==== Welcome Page
Spring Boot supports both static and templated welcome pages.
@ -2576,6 +2589,8 @@ Applications can ensure that such exceptions are recorded with the request metri
If you want to display a custom HTML error page for a given status code, you can add a file to an `/error` directory.
@ -2660,7 +2675,6 @@ To do so, set the `spring.security.filter.dispatcher-types` property to `async,
[[boot-features-spring-hateoas]]
==== Spring HATEOAS
If you develop a RESTful API that makes use of hypermedia, Spring Boot provides auto-configuration for Spring HATEOAS that works well with most applications.
@ -2786,6 +2800,7 @@ Any resources with a path in `+/webjars/**+` are served from jar files if they a
TIP: Spring WebFlux applications do not strictly depend on the Servlet API, so they cannot be deployed as war files and do not use the `src/main/webapp` directory.
[[boot-features-webflux-welcome-page]]
==== Welcome Page
Spring Boot supports both static and templated welcome pages.
@ -3147,6 +3162,7 @@ The `spring-messaging` module of the Spring Framework provides support for RSock
See the {spring-framework-docs}/web-reactive.html#rsocket-spring[RSocket section] of the Spring Framework reference for more details, including an overview of the RSocket protocol.
Spring Boot provides RSocket server auto-configuration.
@ -3455,12 +3472,14 @@ Alternatively, you can define your own `OpaqueTokenIntrospector` bean for servle
[[boot-features-security-authorization-server]]
==== Authorization Server
Currently, Spring Security does not provide support for implementing an OAuth 2.0 Authorization Server.
However, this functionality is available from the {spring-security-oauth2}[Spring Security OAuth] project, which will eventually be superseded by Spring Security completely.
Until then, you can use the `spring-security-oauth2-autoconfigure` module to easily set up an OAuth 2.0 authorization server; see its https://docs.spring.io/spring-security-oauth2-boot/[documentation] for instructions.
[[boot-features-security-saml]]
=== SAML 2.0
@ -3863,6 +3882,7 @@ Both the commercial and open source editions can be used with Spring Boot.
[[boot-features-jooq-codegen]]
==== Code Generation
In order to use jOOQ type-safe queries, you need to generate Java classes from your database schema.
You can follow the instructions in the {jooq-docs}/#jooq-in-7-steps-step3[jOOQ user manual].
@ -3899,6 +3919,7 @@ The following listing shows an example:
[[boot-features-jooq-dslcontext]]
==== Using DSLContext
The fluent API offered by jOOQ is initiated through the `org.jooq.DSLContext` interface.
Spring Boot auto-configures a `DSLContext` as a Spring Bean and connects it to your application `DataSource`.
Unless the configprop:spring.jooq.sql-dialect[] property has been configured, Spring Boot determines the SQL dialect to use for your datasource.
If Spring Boot could not detect the dialect, it uses `DEFAULT`.
@ -3928,6 +3950,7 @@ NOTE: Spring Boot can only auto-configure dialects supported by the open source
[[boot-features-jooq-customizing]]
==== Customizing jOOQ
More advanced customizations can be achieved by defining your own `DefaultConfigurationCustomizer` bean that will be invoked prior to creating the `org.jooq.Configuration` `@Bean`.
This takes precedence to anything that is applied by the auto-configuration.
@ -4417,6 +4440,7 @@ You can choose to disable the repositories support with the following property:
----
[[boot-features-cassandra]]
=== Cassandra
https://cassandra.apache.org/[Cassandra] is an open source, distributed database management system designed to handle large amounts of data across many commodity servers.
If you need to test an auto-configuration that only operates in a Servlet or Reactive web application context, use the `WebApplicationContextRunner` or `ReactiveWebApplicationContextRunner` respectively.
It is also possible to test what happens when a particular class and/or package is not present at runtime.
Spring Boot ships with a `FilteredClassLoader` that can easily be used by the runner.
@ -7422,6 +7447,7 @@ The version can be customized via the `kotlin-coroutines.version` property.
TIP: `org.jetbrains.kotlinx:kotlinx-coroutines-reactor` dependency is provided by default if one bootstraps a Kotlin project with at least one reactive dependency on https://start.spring.io/#!language=kotlin[start.spring.io].
[[boot-features-kotlin-configuration-properties]]
=== @ConfigurationProperties
`@ConfigurationProperties` when used in combination with <<boot-features-external-config-constructor-binding,`@ConstructorBinding`>> supports classes with immutable `val` properties as shown in the following example:
@ -7499,6 +7525,8 @@ The other issue is that putting your application's code and all its dependencies
Since you probably recompile your code more often than you upgrade the version of Spring Boot you use, it’s often better to separate things a bit more.
If you put jar files in the layer before your application classes, Docker often only needs to change the very bottom layer and can pick others up from its cache.
[[boot-layering-docker-images]]
=== Layering Docker Images
To make it easier to create optimized Docker images, Spring Boot supports adding a layer index file to the jar.
@ -7537,9 +7565,14 @@ Spring Boot also supports layering for war files with the help of a `layers.idx`
For Maven, refer to the {spring-boot-maven-plugin-docs}#repackage-layers[packaging layered jar or war section] for more details on adding a layer index to the archive.
For Gradle, refer to the {spring-boot-gradle-plugin-docs}#packaging-layered-archives[packaging layered jar or war section] of the Gradle plugin documentation.
[[boot-features-container-images-building]]
=== Building Container Images
Spring Boot applications can be containerized <<boot-features-container-images-docker,using Dockerfiles>>, or by <<boot-features-container-images-buildpacks,using Cloud Native Buildpacks to create docker compatible container images that you can run anywhere>>.
[[boot-features-container-images-docker]]
==== Dockerfiles
While it is possible to convert a Spring Boot fat jar into a docker image with just a few lines in the Dockerfile, we will use the <<boot-layering-docker-images,layering feature>> to create an optimized docker image.
@ -7601,6 +7634,7 @@ Of course, a Dockerfile can be written without using the jarmode.
You can use some combination of `unzip` and `mv` to move things to the right layer but jarmode simplifies that.
[[boot-features-container-images-buildpacks]]
==== Cloud Native Buildpacks
Dockerfiles are just one way to build docker images.
@ -7621,6 +7655,8 @@ NOTE: In order to achieve reproducible builds and container image caching, Build
You should ensure that your application does not rely on that metadata at runtime.
Spring Boot can use that information when serving static resources, but this can be disabled with configprop:spring.web.resources.cache.use-last-modified[]
[[boot-features-whats-next]]
== What to Read Next
If you want to learn more about any of the classes discussed in this section, you can check out the {spring-boot-api}/[Spring Boot API documentation] or you can browse the {spring-boot-code}[source code directly].
Phillip Webb
4 years ago