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This package contains all Java interfaces and annotations to interact with Microsoft Azure functions runtime.

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/**
 * Copyright (c) Microsoft Corporation. All rights reserved.
 * Licensed under the MIT License. See License.txt in the project root for
 * license information.
 */

package com.microsoft.azure.functions.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;


/**
 *  The warmup trigger lets you define a function that's run when a new instance of your function app is started.
 * You can use a warmup trigger to pre-load custom dependencies during the pre-warming process so your functions are
 * ready to start processing requests immediately. Some actions for a warmup trigger might include opening connections,
 * loading dependencies, or running any other custom logic before your app begins receiving traffic.
 * The parameter type should be set as {@link java.lang.Object}
 *
 *
 * The following example shows a Java function that logs the message body of the event hub trigger:
 *
 * {@literal @}FunctionName("Warmup")
 * public void warmup(
 *    {@literal @}WarmupTrigger Object warmupContext,
 *     final ExecutionContext context
 * ) {
 *     context.getLogger().info("Function App instance is warm up");
 * }
 *
 * @since 2.0.2
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.PARAMETER)
@CustomBinding(direction = "in", name = "warmupContext", type = "warmupTrigger")
public @interface WarmupTrigger {
    /**
     * The variable name used in function code for the request or request body.
     *
     * @return The variable name used in function code for the request or request body.
     */
    String name() default "warmupContext";

    /**
     * Defines how Functions runtime should treat the parameter value. Possible values are:
     * 
     *     "": get the value as a string, and try to deserialize to actual parameter type like POJO
     *     string: always get the value as a string
     *     binary: get the value as a binary data, and try to deserialize to actual parameter type byte[]
     * 
     * @return The dataType which will be used by the Functions runtime.
     */
    String dataType() default "";
}