Table of Contents

• 1. Summary
• 2. Links
• 3. Error Handling in MuleSoft 4:
• 4. HTTP Status
  • 4.1. HTTP Status Codes

• ❏ Listener in different port to Reply specific HTTP status codes

• ❏ Scopes

  • ❏ Try Scope

  • ❏ Until Successful

  • ❏ On Error Propagate

    • ❏ On Error Continue inside On Error Propagate, validate what happens with the first error after an error occurs inside the On Error Propagate

  • ❏ On Error Continue

1. Summary

This application demonstrates how to use the MuleSoft 4 error handling in different scenarios with different types of errors.

It includes examples of how to handle errors in a MuleSoft application, including connectivity errors, validation errors, and transformation errors.

2. Links

• Mule Errors | MuleSoft Documentation

• Predefined Variables | MuleSoft Documentation

• Introduction to Mule 4: Error Handlers | MuleSoft Documentation

3. Error Handling in MuleSoft 4:

MuleSoft 4 provides a robust error handling framework to manage and respond to errors effectively.

The error handling mechanism is based on the following key components:

1. Error Types:

   • MuleSoft categorizes errors into different types (e.g., CONNECTIVITY, VALIDATION, TRANSFORMATION).

   • Each error type has a namespace and a specific error code.

2. Error Handlers:

   • On Error Continue: Allows the flow to continue execution after handling the error.

   • On Error Propagate: Propagates the error to the parent flow or caller after handling it.

3. Scopes:

   • Try Scope:

     • Encapsulates a block of code that may throw an error.

     • Allows you to define specific error handling logic for that block.

   • Until Successful Scope:

     • Repeats a block of code until it succeeds or reaches a maximum

4. Error Propagation:

   • Errors can be propagated to higher levels in the flow hierarchy.

   • Use raise-error to explicitly raise custom errors.

5. Logging and Debugging:

   • Use the Logger component to log error details for debugging purposes.

   • Access error attributes such as error.description, error.errorType.namespace, error.errorType.identifier, and error.detailedDescription.

6. Global Error Handling:

   • Define global error handlers to manage errors across multiple flows.

   • Use the Error Handler component at the application level.

Example Use Case: A flow that connects to an external API might use a Try scope to handle connectivity errors. If an error occurs, an On Error Continue block can log the error and provide a fallback response.

Best Practices: Always handle errors explicitly to avoid unexpected application behavior. Use meaningful error messages and codes for better debugging and maintenance. ** Test error scenarios thoroughly to ensure the application behaves as expected.

4. HTTP Status

The application tries to mock a variety of HTTP status codes, including:

Reference:

• HTTP response status codes - HTTP | MDN

• HyperText Transfer Protocol (HTTP) explained

4.1. HTTP Status Codes

• 200 OK

• 201 Created

• 202 Accepted

• 204 No Content

• 205 Reset Content

• 206 Partial Content

• 208 Already Reported / Conflict

• 400 Bad Request

• 401 Unauthorized

• 402 Payment Required

• 403 Forbidden

• 404 Not Found

• 405 Method Not Allowed

• 406 Not Acceptable

• 408 Request Timeout

• 409 Conflict

• 410 Gone

• 411 Length Required

• 412 Precondition Failed

• 413 Content Too Large

• 414 URI Too Long

• 415 Unsupported Media Type

• 422 Unprocessable Entity

• 426 Upgrade Required

• 428 Precondition Required

• 429 Too Many Requests

• 431 Request Header Fields Too Large

• 451 Unavailable For Legal Reasons

• 500 Internal Server Error

• 501 Not Implemented

• 502 Bad Gateway

• 503 Service Unavailable

• 504 Gateway Timeout

• 507 Insufficient Storage

• 508 Loop Detected

• 511 Network Authentication Required