Creating Handlers | Tasks And Handlers

Introduction

Handlers are essential components in CrewAI, enabling the system to execute tasks based on specific triggers and conditions. This tutorial will guide you through the process of creating handlers from start to finish, with detailed explanations and examples.

Understanding Handlers

A handler in CrewAI is responsible for managing the execution of tasks when certain events occur. Handlers are defined in the configuration files or directly in the code, depending on the complexity and requirements of the tasks.

Step 1: Define Your Task

Before creating a handler, you need to define the task that will be executed. For example, let's create a simple task that logs a message.

{
    "task": {
        "name": "LogMessage",
        "action": "log",
        "message": "This is a log message from CrewAI."
    }
}

Step 2: Create the Handler

Next, you need to create a handler that will execute the task when triggered. Handlers can be created in the configuration file or directly in the code. Here, we'll define a handler in the configuration file.

{
    "handler": {
        "name": "LogHandler",
        "event": "onStart",
        "tasks": ["LogMessage"]
    }
}

Step 3: Register the Handler

After defining the handler, you need to register it in the system so that it can be recognized and executed when the specified event occurs. This can be done in the main configuration file of your CrewAI project.

{
    "handlers": ["LogHandler"]
}

Step 4: Testing the Handler

Finally, you need to test the handler to ensure it works as expected. Start your CrewAI application and check the logs to see if the message is logged when the application starts.

crewai start

2023-10-10 10:10:10 INFO LogMessage: This is a log message from CrewAI.

Conclusion

In this tutorial, you learned how to create handlers in CrewAI. By following these steps, you can define tasks, create handlers, register them, and test their functionality. Handlers are a powerful feature in CrewAI that help automate and manage task execution efficiently.

Creating Handlers in CrewAI