Package com.google.genkit.plugins.middleware

Class GenerationMiddlewarePlugin

java.lang.Object

com.google.genkit.plugins.middleware.GenerationMiddlewarePlugin

All Implemented Interfaces:

MiddlewarePlugin, Plugin

public class GenerationMiddlewarePlugin
extends Object
implements Plugin, MiddlewarePlugin

A plugin that ships a set of ready-to-use, parameterized generation middleware.

This is the Java analog of the JS @genkit-ai/middleware package and the Go plugins/middleware package. Adding it to the Genkit builder registers each middleware into the "middleware" registry bucket, so it appears in the Genkit Dev UI Middleware panel (with a parameters form derived from its configSchema) and can be attached to any generate() call by name.

Provided middleware:

• retry — retry failed model calls with exponential backoff (RetryMiddleware)
• fallback — fall back to alternate models on failure (FallbackMiddleware)
• simulateSystemPrompt — rewrite the system message into a user/model exchange (SimulateSystemPromptMiddleware)

Usage:

 Genkit genkit = Genkit.builder()
     .plugin(OpenAIPlugin.create())
     .plugin(GenerationMiddlewarePlugin.create())
     .build();

 // Attach by name (config optional) from code or the Dev UI:
 genkit.generate(GenerateOptions.builder()
     .model("openai/gpt-4o-mini")
     .prompt("Hello")
     .build());
 

Field Summary

Fields

Modifier and Type	Field	Description
static final String	PLUGIN_NAME	The plugin name.

Constructor Summary

Constructors

Constructor	Description
GenerationMiddlewarePlugin()

Method Summary

Modifier and Type	Method	Description
static GenerationMiddlewarePlugin	create()	Creates the plugin.
String	getName()	Returns the unique identifier for the plugin.
List<Action<?,?,?>>	init()	Initializes the plugin.
List<GenerationMiddlewareDesc>	middlewares(Registry registry)	Returns the generation middleware this plugin provides.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.google.genkit.core.Plugin

init

Field Details

PLUGIN_NAME

public static final String PLUGIN_NAME

The plugin name.

See Also:

• Constant Field Values

Constructor Details

GenerationMiddlewarePlugin

public GenerationMiddlewarePlugin()

Method Details

create

public static GenerationMiddlewarePlugin create()

Creates the plugin.

Returns:

a new plugin instance

getName

public String getName()

Description copied from interface: Plugin

Returns the unique identifier for the plugin. This name is used for registration and lookup.

Specified by:

getName in interface Plugin

Returns:

the plugin name

init

public List<Action<?,?,?>> init()

Description copied from interface: Plugin

Initializes the plugin. This method is called once during Genkit initialization. The plugin should return a list of actions that it provides.

Specified by:

init in interface Plugin

Returns:

list of actions provided by this plugin

middlewares

public List<GenerationMiddlewareDesc> middlewares(Registry registry)

Description copied from interface: MiddlewarePlugin

Returns the generation middleware this plugin provides. Called once during Genkit initialization.

Specified by:

middlewares in interface MiddlewarePlugin

Parameters:

registry - the Genkit registry, for middleware that needs to resolve dependencies (e.g. a fallback middleware that runs other models)

Returns:

the middleware descriptors to register (may be empty)