MCD-Level-1 Exam Dumps - MuleSoft Certified Developer - Level 1 (Mule 4)

Correct answer is Anypoint Visualizer

MuleSoft Doc Ref : https://docs.mulesoft.com/visualizer/

Anypoint Visualizer provides a real-time, graphical representation of the APIs, and Mule applications that are running and discoverable. It also displays third-party systems that are invoked by a Mule API, proxy, or application within your application network. The data displayed in the graph is dynamically updated and does not require prior configuration. Additionally, the data displayed is secure, as only users with the proper permissions can view the application network graph.

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Correct answer is as below. Attributes in the incoming xml payload are always accessed using @.Similarly *item is required as we have multiple items in the request

%dw 2.0

output application/csv

---

payload.sale.*item map ((value, index) -> {

index: index,

sale: value.@saleId,

itemName: value.desc,

itemPrice: (value.quantity) * (value.price),

item: value.@itemId

} )

To compare, DataWeave syntax is #[payload == "FR"].

In this case only one = is used so it will give syntax error.

Hence the correct answer is A dataweave syntax error

As can be seen in error message , SOAP service findFlights expects the SOAP paylaod. This can be set using transform message processor which forms SOAP payload before the Consume operation that contains the destination query parameter

API Exchange creates REST conenctor automtaically once API is published. Hence correct answer is Publish the API specification to Any point Exchange

Correct answer is below as it follows the correct syntax.

/customers:

/{customerId}:

get:

Correct answer is Creates and manages discoverable assets to be consumed by line of business developers.

C4E does not get directly involved in projects.

The APIkit Router is a key message processor that validates requests against the provided definition, enriches messages (for example by adding default values to the messages) and routes requests to a particular flow. Also, the Router raises errors messages if errors occurs while routing, validating or processing the user request.

Correct answer is Creates a mock service for an API

API Notebook is an open source, shareable web application for API documentation, interactive API tutorial and example generatation, and a client for your API endpoints. Using API Notebook, you can make requests and quickly transform the responses into readable format. However it cannot be used to mock service for an API.

MuleSoft Doc Ref : https://docs.mulesoft.com/api-manager/1.x/api-notebook-concept

WSDL is used to define the contract in case of SOAP . RAML/OAS is used to REST services

lookup(String, Any, Number)

This function enables you to execute a flow within a Mule app and retrieve the resulting payload.

It works in Mule apps that are running on Mule Runtime version 4.1.4 and later.

Similar to the Flow Reference component (recommended), the lookup function enables you to execute another flow within your app and to retrieve the resulting payload. It takes the flow’s name and an input payload as parameters. For example, lookup("anotherFlow", payload) executes a flow named anotherFlow.

Correct answer is

lookup( "createCustomerObject", {first: "Aice, last: "Green"})

MuleSoft Documentation Reference : https://docs.mulesoft.com/mule-runtime/4.3/dw-mule-functions-lookup

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

Points to remember:

* XML must have a root element.

* XML only allows one root element

* To avoid multiple root issues, you must create a root element for the XML output, whenever we transform output

* When mapping array elements (JSON or JAVA) to XML, wrap the map operations in {(..)}

-{ } are defining the object

( ) are transforming each element in the array as a key/value pair

* The transformation to XML would fail if the above mentioned considerations were not taken into account.

* Thus the transformation script declares a root element as trains and wraps the data in “{( )}“.

Whenever you see such type of question, always look out for root element followed by {( )} wrapping map.

I call this a "Wrap The Map" scenario. Hope it would help you remember !

Option 2 is the correct answer as /api/* accespts everything starting with /api/

* Batch scope has filter criteria which says paylod mod 2 = 0 whch means only 2, 4 and 6 will be in batch scope.

* So payload for each of these will be incremented by 10.

* Aggregator has batch size defined as 2. So it will process in batch of two records.

* Hence option 3 is correct answer.

[20,40]

[60]

Behavior with aggregator configured with fixed size

In this scenario, the batch step sends the processed records to an aggregator, which starts processing the records and buffering them until the configured aggregator’s size is reached. After that, the aggregator sends the aggregated records to the stepping queue.

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The batch job builds record blocks of the configured block size and sends them to their corresponding batch step for processing. Each batch step receives one or more record blocks and starts processing them in parallel. After the batch step processes a record, the batch step sends the record to the aggregator for further processing. The aggregator continues processing records until the number of aggregated records reaches the configured aggregator’s size.

https://docs.mulesoft.com/mule-runtime/4.3/batch-processing-concept

Only one of the routes in the Choice router executes, meaning that the first expression that evaluates to true triggers that route1 execution and the others are not checked. If none of the expressions are true, then the default route executes. Hence only Route1 will be executed as it is the first expression. hence output of logger is Route1.

MuleSoft Doc Ref : https://docs.mulesoft.com/mule-runtime/4.3/choice-router-concept

The Choice router dynamically routes messages through a flow according to a set of DataWeave expressions that evaluate message content. Each expression is associated with a different routing option. The effect is to add conditional processing to a flow, similar to an if/then/else code block in most programming languages.

Only one of the routes in the Choice router executes, meaning that the first expression that evaluates to true triggers that route’s execution and the others are not checked. If none of the expressions are true, then the default route executes.

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Correct answer is Subflow has no error handling implementation where as sync flow has.

Subflow

A subflow processes messages synchronously (relative to the flow that triggered its execution) and always inherits both the processing strategy and exception strategy employed by the triggering flow. While a subflow is running, processing on the triggering flow pauses, then resumes only after the subflow completes its processing and hands the message back to the triggering flow.

Synchronous Flow

A synchronous flow, like a subflow, processes messages synchronously (relative to the flow that triggered its execution). While a synchronous flow is running, processing on the triggering flow pauses, then resumes only after the synchronous flow completes its processing and hands the message back to the triggering flow. However, unlike a subflow, this type of flow does not inherit processing or exception strategies from the triggering flow.

This type of flow processes messages along a single thread, which is ideally suited to transactional processing

This kind of questions are best solved with filtering technique. Key thing to note here is XML attributes are always access by @ notation. So in this example orderId can be accessed as @OrderId which makes option 3 and option 4 false. Now difference in optin and option 2 is in mapping of lineItemPrice. Correct syntax to format a String in Numbse is value.price as Number. Hence option 2 is correct

In this case as outbound call is made using HTTP: POST /child , all attributes will be replaced by this invocation. Hence query parameter will not be accessible at logger.

Query parameters are a defined set of parameters attached to the end of a url. They are extensions of the URL that are used to help define specific content or actions based on the data being passed. To append query params to the end of a URL, a ‘?’ Is added followed immediately by a query parameter.

To add multiple parameters, an ‘&’ is added in between each.

Hence coming back to question, endpoint would return Patients with name as John and (and is very important here) surname as Bell

Correct answer is Publish the API to Anypoint Exchange

Anypoint Exchange makes this possible by making it discoverable in below ways

1) In private exchange for internal developers

2) In a public portal for external developers/clients

Here is diagram created by me to help you understand sequence:

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

Option 1 is the correct syntax

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

Correct answer is Change the method attributes value to "POST".

It can be fixed in either of the two ways as below.

1) Changing method attribute to POST in ClientRequestFlow

2) Setting allowedMethods as PUT in ShippingFlow (but doesn't fit as question mentions about changing ClientRequestFlow)

Correct answer is Array.

Flatten turns a set of subarrays (such as [ [1,2,3], [4,5,[6]], [], [null] ]) into a single, flattened array (such as [ 1, 2, 3, 4, 5, [6], null ]).

This example defines three arrays of numbers, creates another array containing those three arrays, and then uses the flatten function to convert the array of arrays into a single array with all values.

Source

%dw 2.0

output application/json

var array1 = [1,2,3]

var array2 = [4,5,6]

var array3 = [7,8,9]

var arrayOfArrays = [array1, array2, array3]

---

flatten(arrayOfArrays)

Output

[ 1,2,3,4,5,6,7,8,9 ]

The flow can be described as below. 1) First HTTP POST requets is made in which paylaod is set to 1 and it gets returned to our mail flow. 2) Second call is initiated for JMS Publish Consume JMS: num1 which add 1 to the payload which makes it as 2. Note that pubih consume is a synchronous operation. Hence paylaod is returned to main flow. 3) Third call is initiated for JMS Publish JMS: num2 which add 1 to the payload . Note that pubih is asynchronous operation. Hence paylaod is never returned to main flow. So payload in main flow is still 2. 4) Finally Set Payload increments payload by 1 making payload as 3 which is returned by the flow. Hence option 3 is the correct answer.

Correct syntax to use where clause is WHERE city = :city AND state = :state

This question validates knowledge on using dynamic queries in DB select operation.

Configure Dynamic Queries in the Select Operation

When you need to parameterize not only the WHERE clause but also parts of the query itself (for example, queries that compare tables that depend on a condition, or complex queries for which the project table columns need to vary), you can configure dynamic queries.

In the following example, you configure a dynamic query by using a full expression with a string in which the table depends on a variable $(vars.table). Although some of the query text is dynamic ("SELECT * FROM $(vars.table)), the WHERE clause still defines the WHERE condition using input parameters: in this case, WHERE name = :name.

In your Studio flow, select the Select operation.

In the operation configuration screen, set the SQL Query Text field to SELECT * FROM $(vars.table) WHERE name = :name.

Set the Input Parameters field to {'name' : payload}.

The following screenshot shows the configuration in Studio:

Graphical user interface, application Description automatically generated

Figure 3. Dynamic query configuration

In the XML editor, the  configuration looks like this:

• #["SELECT * FROM $(vars.table) WHERE name = :name"]
• #[{'name' : payload}]

You can apply input parameters only to parameters in a WHERE clause. To modify any other part of the query, use the DataWeave interpolation operator.

Mule Ref Doc: Query a Database Examples - Mule 4 | MuleSoft Documentation

First step in creating Modern API is to create an API specification and get feedback from stakeholders so that any future issues can be identified at early stage thereby reducing overall delivery time

Setting Breakpoints

To set breakpoints, right-click a building block, then select Toggle Breakpoint.

Studio applies a red dot to the building block’s icon on the canvas.

When you run your application in Debug mode, Studio stops the flow execution at the breakpoint you have set, allowing you to check the Mule Event content in the Mule Debugger View.

Mule Ref Doc : Setting Breakpoints | MuleSoft Documentation

The correct answer is To avoid duplicate processing of records in a database.

If a watermark column is provided, the values taken from that column are used to filter the contents of the next poll, so that only rows with a greater watermark value are returned. If an ID column is provided, this component automatically verifies that the same row is not picked twice by concurrent polls.

Mule doc reference : https://docs.mulesoft.com/db-connector/1.8/database-documentation#listener

Pick First is not valid type. Rest all are valid type of event processor.

Choice : https://docs.mulesoft.com/mule-runtime/4.3/choice-router-concept

Round Robin : https://docs.mulesoft.com/mule-runtime/4.3/round-robin

First Successful : https://docs.mulesoft.com/mule-runtime/4.3/first-successful

In case of an error , batch job completes in flight steps and stops further processing.

MuleSoft Doc Ref : Handling Errors During Batch Job | MuleSoft Documentation

The default is all processing will stop but we can change it by Max Failed Record field.

General -> Max Failed Records: Mule has three options for handling a record-level error: Finish processing, Continue processing and Continue processing until the batch job accumulates a maximum number of failed records. This behavior can be controlled by Max Failed Records.

The default value is Zero which corresponds to Finish processing.

The value -1, corresponds to Continue processing.

The value +ve integer, corresponds to Continue processing until the batch job accumulates a maximum number of failed records

Correct answer is APP: API RESOURCE NOT FOUND

---------------------------------------------------------------------------------------------------------------------------------------------------

1) A web client submits the request to the HTTP Listener.

2) The HTTP Request throws an "HTTP:NOT_FOUND" error, execution halts.

3) The On Error Propagate error Handler handles the error. In this case ,HTTP:NOT_FOUND error is mapped to custom error APP:API_RESOURCE_NOT_FOUND. This error processor sets payload to APP:API_RESOURCE_NOT_FOUND.

4) “APP:API_RESOURCE_NOT_FOUND. ” is the error message returned to the requestor in the body of the HTTP request with HTTP Status Code: 500

Reference Diagram:

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Correct answer is as below as concatenation operation works only with string and not with the objects. In this case payload is object.

"You called the function '++' with these arguments:

1: String ("INFO")

2: Object ({student: {name: "Anay" as String {class: "java.lang.String"},age

Correct answer is [[5, 10, 15, 20], 5]

Key thing to note here is that any changes made to payload in for each loop are not available outside for each scope where as variable value updated in for each loop is visible out side for each loop too.

In this example , sequence can be described as follows

1) Payload is set to the value [5, 10, 15, 20]

2) Variable is set to the value of 1

3) For each loop is executed four times and in each loop payload value is updated to append "Req" and variable is count is increased by 1

4) Once control comes out of for each , payload changes made within for each are not visible. Hence payload at this point of time is equal to payload available before entering for each loop which was  [5, 10, 15, 20]. Similarly variable value updated in for each loop is also available outside hence variable value is 5 as it was updated in loop.

5) Hence correct answer is [[5, 10, 15, 20], 5]

For Each Scope

The For Each scope splits a payload into elements and processes them one by one through the components that you place in the scope. It is similar to a for-each/for loop code block in most programming languages and can process any collection, including lists and arrays. The collection can be any supported content type, such as application/json, application/java, or application/xml.

General considerations about the For Each scope:

By default, For Each tries to split the payload. If the payload is a simple Java collection, the For Each scope can split it without any configuration. The payload inside the For Each scope is each of the split elements. Attributes within the original message are ignored because they are related to the entire message.

For Each does not modify the current payload. The output payload is the same as the input.

For non-Java collections, such as XML or JSON, use a DataWeave expression to split data. Use the Collection field for this purpose.

Anypoint Exchange provided a way to publish , share and search API's.

MuleSoft Doc Ref : https://docs.mulesoft.com/exchange/

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 The API interfaces are specified at a granularity intended for developers to consume specific aspect of integration processes

For such questions always look for Syntax:

I call it "Wrap the Map"

trains:

{(

When mapping array elements (JSON or JAVA) to XML, wrap the map operations in {(..)}

-{ } are defining the object

-( ) are transforming each element in the array as a key/value pair

Correct answer is as below. In this case address will be stored in a variable. Hence payload will not be overwritten and will contain order details

{

orderkey: "payload.order",

addresskey: "vars.address"

}

This is a trick question.

You can call only flows from DataWeave using lookup function. Note that lookup function does not support calling subflows.

A subflow needs a parent context to inherit behaviors from such as exception handling, which a flow does not need

Hence correct answer is Not possible in Mule 4

Correct answer is MAJOR

MAJOR version when you make incompatible API changes, MINOR version when you add functionality in a backwards compatible manner, and PATCH version when you make backwards compatible bug fixes.

For details refer to this documentation : https://semver.org/