The MuleSoft Certified Developer - Level 1 (Mule 4) (MCD-Level-1)

PUT replaces the original version of the resource, whereas the PATCH method supplies a set of instructions to modify the resource

Scatter-Gather sends the event to each routes concurrently. Hence both route in this example will start in parallel. So total time to complete processing is 40 seconds

The Scatter-Gather component is a routing event processor that processes a Mule event through different parallel processing routes that contain different event processors. Each route receives a reference to the Mule event and executes a sequence of one or more event processors. Each of these routes uses a separate thread to execute the event processors, and the resulting Mule event can be either the same Mule event without modifications or a new Mule event with its own payload, attributes, and variables. The Scatter-Gather component then combines the Mule events returned by each processing route into a new Mule event that is passed to the next event processor only after every route completes successfully.

The Scatter-Gather component executes each route in parallel, not sequentially. Parallel execution of routes can greatly increase the efficiency of your Mule application and may provide more information than sequential processing.

Mule Ref Doc :  https://docs.mulesoft.com/mule-runtime/4.3/scatter-gather-concept

Correct answer is Nothing needs to be changed in the other APIs or their associated applications

This is the benefit of having separate interface layer. As there are no changes to interface , no changes are required on the API ' s which consumes this API in context

Mule event is correct answer. Mule event has two parts which are as follows

1) Message (which contains payload and attributes like headers and query/uri parameters

2) Variables

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Note that private flow has error scope defined as On Error Continue . So when error occurs in private flow , it is handled by this On Error Continue scope which sends success response back to main flow and does not throw back an error. So main continues normally and payload is set to Success - main flow.

Hence correct answer is  Success - main flow

1) HTTP listener received request

2) The Flow Reference calls the child flow

3) The Is Number validator creates an Error Object because the payload isn’t an integer. Child Flow execution stops

#[error.description] = “payload is not a valid INTEGER value”

#[error.errorType] = VALIDATION:INVALID_NUMBER

4) The On Error Continue handles the errorThe payload is set to “Error – Sub Flow”

5) “Error – Sub Flow” is returned to the main flow as if the child flow was a success. The Set Payload is executed. The payload is reset to “Success – Finished Main Flow”

6) “Success – Main Flow” is returned to the requestor in the body of the HTTP request. HTTP Status Code: 200

As you can see, in the above example, because the error was caught by an On Error Continue scope in the child flow (RED in, GREEN out) when the Mule Message returns to the parent flow, the parent flow knows none-the-different that there was a failure because the on error continue returns a 200 success message. Note that because, to the mainFlow, the childFlow appeared to succeed, the processing of mainFlow resumed after the flow reference.

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Core (dw::Core) This module contains core DataWeave functions for data transformations. It is automatically imported into any DataWeave script.

In this case both the flows can start without any error and requests can be received on both ports. Flow names httpListener1 can call other flow using HTTP request without any issues.

Hence correct answer is

The mule application start successfully

Web client requests can  be received at URI on port 2222 and on port 3333.

Lets check why other options are incorrect

1) The mule application fails to start. There is URL path conflict because both HTTP Listeners are configured with same path  ---- This is incorrect as port value is different in both listeners

2) The mule application start successfully. Web client requests can only be received at URI on port 2222 but not on port 3333  --- This is incorrect as there is no reason for not receiving requests on port 3333

3) The mule application fails to start because of the port binding conflict as HTTP request also use same port i.e. 3333 --- Port binding conflict will not happen in this case. It would have if both listener configurations would have been on same port . But that is not the case here.

Mule Ref Doc :  HTTP Listener Reference - Mule 4 | MuleSoft Documentation