Introducing springdoc-openapi-gradle-plugin

Gradle plugin for springdoc-openapi.

This plugin allows you to generate an OpenAPI 3 specification for a Spring Boot application from a Gradle build. Compatibility Notes

The plugin is built on Gradle version 7.0.

Dependencies

This plugin has a runtime dependency on the following plugins:

1. Spring Boot Gradle plugin - org.springframework.boot
2. Gradle process plugin - com.github.psxpaul.execfork

How To Use

Gradle Groovy DSL

plugins {
    id "org.springframework.boot" version "2.7.0"
    id "org.springdoc.openapi-gradle-plugin" version "1.9.0"
}

Gradle Kotlin DSL

plugins {
    id("org.springframework.boot") version "2.7.0"
    id("org.springdoc.openapi-gradle-plugin") version "1.9.0"
}

Note: For latest versions of the plugins please check the Gradle Plugins portal.

How the plugin works?

When you add this plugin and its runtime dependency plugins to your build file, the plugin creates the following tasks:

1. forkedSpringBootRun

2. generateOpenApiDocs

Running the task generateOpenApiDocs writes the OpenAPI spec into a openapi.json file in your project's build dir.

gradle generateOpenApiDocs

When you run the gradle task generateOpenApiDocs, it starts your spring boot application in the background using forkedSpringBootRun task. Once your application is up and running generateOpenApiDocs makes a rest call to your applications doc url to download and store the open api docs file as json.

Customization

The following customizations can be done on task generateOpenApiDocs using extension openApi as follows

openApi {
	apiDocsUrl.set("https://localhost:9000/api/docs")
	outputDir.set(file("$buildDir/docs"))
	outputFileName.set("swagger.json")
	waitTimeInSeconds.set(10)
	trustStore.set("keystore/truststore.p12")
	trustStorePassword.set("changeit".toCharArray())
	groupedApiMappings.set(
		["https://localhost:8080/v3/api-docs/groupA" to "swagger-groupA.json",
			"https://localhost:8080/v3/api-docs/groupB" to "swagger-groupB.json"]
	)
	customBootRun {
		args.set(["--spring.profiles.active=special"])
	}
	requestHeaders = [
		"x-forwarded-host": "custom-host",
	"x-forwarded-port": "7000"
	]
}

Parameter	Description	Required	Default
apiDocsUrl	The URL from where the OpenAPI doc can be downloaded. If the url ends with .yaml, output will YAML format.	No	http://localhost:8080/v3/api-docs
outputDir	The output directory for the generated OpenAPI file	No	$buildDir - Your project's build dir
outputFileName	Specifies the output file name.	No	openapi.json
waitTimeInSeconds	Time to wait in seconds for your Spring Boot application to start, before we make calls to apiDocsUrl to download the OpenAPI doc	No	30 seconds
trustStore	Path to a trust store that contains custom trusted certificates.	No	<None>
trustStorePassword	Password to open Trust Store	No	<None>
groupedApiMappings	A map of URLs (from where the OpenAPI docs can be downloaded) to output file names	No	[]
customBootRun	Any bootRun property that you would normal need to start your spring boot application.	No	(N/A)
requestHeaders	customize Generated server url, relies on server.forward-headers-strategy=framework	No	(N/A)

customBootRun properties examples

customBootRun allows you to send in the properties that might be necessary to allow for the forked spring boot application that gets started to be able to start (profiles, other custom properties, etc.) customBootRun allows you can specify bootRun style parameter, such as args, jvmArgs, systemProperties and workingDir. If you don't specify customBootRun parameter, this plugin uses the parameter specified to bootRun in Spring Boot Gradle Plugin.

Passing static args

This allows for you to be able to just send the static properties when executing Spring application in generateOpenApiDocs.

openApi {
    customBootRun {
        args = ["--spring.profiles.active=special"] 
    }
}

Passing straight from gradle

This allows for you to be able to just send in whatever you need when you generate docs.

./gradlew generateOpenApiDocs -Dspring.profiles.active=special

and as long as the config looks as follows that value will be passed into the forked spring boot application.

openApi {
    customBootRun {
         systemProperties = System.properties
    }
}

Trust Store Configuration

If you have restricted your application to HTTPS only and prefer not to include your certificate in Java's cacerts file, you can configure your own set of trusted certificates through plugin properties, ensuring SSL connections are established.

Generating a Trust Store

To create your own Trust Store, utilize the Java keytool command:

keytool -storepass changeit -noprompt -import -alias ca -file [CERT_PATH]/ca.crt -keystore [KEYSTORE_PATH]/truststore.p12 -deststoretype PKCS12

Grouped API Mappings Notes

The groupedApiMappings customization allows you to specify multiple URLs/file names for use within this plugin. This configures the plugin to ignore the apiDocsUrl and outputFileName parameters and only use those found in groupedApiMappings. The plugin will then attempt to download each OpenAPI doc in turn as it would for a single OpenAPI doc.

Building the plugin

1. Clone the repo git@github.com:springdoc/springdoc-openapi-gradle-plugin.git
2. Build and publish the plugin into your local maven repository by running the following

   ./gradlew clean pTML
   

Testing the plugin

1. Create a new spring boot application or use an existing spring boot app and follow the How To Use section above to configure this plugin.

2. Update the version for the plugin to match the current version found in build.gradle.kts

   id("org.springdoc.openapi-gradle-plugin") version "1.8.0"
   

3. Add the following to the spring boot apps settings.gradle

   pluginManagement {
       repositories {
           mavenLocal()
           gradlePluginPortal()
       }
   }
   

Thank you for the support

• Thanks a lot JetBrains for supporting springdoc-openapi project.