MCD-Level-1 Practice Exam Questions with Answers MuleSoft Certified Developer - Level 1 (Mule 4) Certification

The First Successful router iterates through a list of configured processing routes until one of the routes executes successfully. This is sequential execution. In all other options mentioned in the question ,we can achieve parallel execution.

Correct answer is ${training.host}

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How to Configure Properties to Mule 4.X Platform?

1) Go to /src/main/resources project directory.

2) Create a configuration file with the name configuration.yaml inside the newly created config folder.

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3) Go To Project > Global Element > Create > General >select the configuration.yaml file create in step- 2)

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4) To verify develop a simple flow with HTTP listener which has above entries. Put the logger that prints the values on console.

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5) Additional info: Similarly, when you want to access this port in DataWeave you need to use p function

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This question validates you knowledge on Batch Processing. Before we analyze the question , lets revise a bit about batch filters.

Batch Filters

You can apply one or more filters as attributes to any number of batch steps.Imagine a batch job whose first batch step checks if a Salesforce contact exists for a record, and a second batch step that updates each existing Salesforce contact with new information. You can apply a filter to the second batch step to ensure it only processes records that didn’t fail during the first batch step.By having batch steps accept only some records for processing, you streamline the batch job so the Mule runtime engine can focus only on the relevant data for a particular batch step.

A batch step uses two attributes to filter records:

acceptExpression

acceptPolicy

Each batch step can accept one acceptExpression and one acceptPolicy attributes to filter records.

Use the acceptExpression attribute to process only records that evaluate to true; if the record evaluates to false, the batch step skips the record and sends it to the next one. In other words, the records with an accept expression that resolves to false are the ones that Mule filters out.

The example below filters out all records where the age is less than 21; the batch step does not process those records.

• ...

Mule Ref Doc : Refining Batch Steps Processing | MuleSoft Documentation

As we are clear with above concepts , now lets understand this solution step by step.

1) Batch Step (Less than 50)

Accept expression for this batch step is less than 50. Hence elements which will go in this batch step are amount value 40 and 2. Hence output of logger in first batch step is

{amount=140}

{amount=102}

2) Batch Step (Greater than 20)

Accept condition for this batch step is greater than 20. Note that input amount values for this batch step are 100 , 140 and 102 (last two values have been updated in batch step less than 50)

As all values satisfy this condition out put of second logger is

{step2amount=100}

{step2amount=140}

{step2amount=102}

Hence correct answer to this question is

• {amount=140}
• {amount=102}
• {step2amount=100}
• {step2amount=140}
• {step2amount=102}

2) Batch Step (Greater than 20)

Accept condition for this batch step is greater than 20. Note that input amount values for this batch step are 100 , 140 and 102 (last two values have been updated in batch step less than 50)

As all values satisfy this condition out put of second logger is

{step2amount=100}

{step2amount=140}

{step2amount=102}

Hence correct answer to this question is

{amount=140}

{amount=102}

{step2amount=100}

{step2amount=140}

{step2amount=102}

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

* Watermark allows the poll scope to poll for new resources instead of getting the same resource over and over again.

* The database table must be ordered so that the “watermark functionality” can move effectively in the ordered list. Watermark stores the current/last picked up “record id.”

* If the Mule application is shut down, it will store the last picked up “record id” in the Java Object Store and the data will continue to exist in the file. This watermark functionality is valuable and enables developers to have increased transparency.

* Developers do not need to create code to handle caching; it is all configurable!

* There are two columns and both are unique but user_id can't guaranty sequence whereas date_time will always be in increasing order and table content can easily be ordered on the basis of last processed date_time.

So correct answer is: Set the watermark column to the date_time column

Lets revise few concepts RAML which can help us to find the answer of this question.

URI Parameters

Lets have a look at below example.

• /foos:
• /{id}:
• /name/{name}:

Here, the braces { } around property names define URI parameters. They represent placeholders in each URI and do not reference root-level RAML file properties as we saw above in the baseUri declaration. The added lines represent the resources /foos/{id} and /foos/name/{name}.

Query Parameters

Now we'll define a way to query the foos collection using query parameters. Note that query parameters are defined using the same syntax that we used above for data types:

• /foos:
• get:
• description: List all Foos matching query criteria, if provided;
• otherwise list all Foos
• queryParameters:
• name?: string
• ownerName?: string

Based on the above information , below is the only option which defines storeid as uri parameter and department as query parameter.

• /{storeId}:
• get:
• queryParameter:
• department:

As can be seen in RAML, POST expects input in application/json format which eliminates two of the options as two options are in xml format.

Now out of the two remaining options, one has id field in request which is only mentioned for get response and not for POST request. Hence id field is not expected in POST request.

Hence correct answer is

{

"name": "GoerdiLa Forge",

"address": "1 Westland CA",

"customer_since": "2014-01-04",

"balance": "4829.29",

"bank_agend_id": "12556"

}

Mule applications can be scaled vertically by changing worker size. Mule applications can be scaled horizontally by adding more workers.

Entire event would be sent to each route in parallel.

Scatter-Gather works as follows :

- The Scatter-Gather component receives a Mule event and sends a reference of this Mule event to each processing route.

- Each of the processing routes starts executing in parallel. After all processors inside a route finish processing, the route returns a Mule event, which can be either the same Mule event without modifications or a new Mule event created by the processors in the route as a result of the modifications applied.

- After all processing routes have finished execution, the Scatter-Gather component creates a new Mule event that combines all resulting Mule events from each route, and then passes the new Mule event to the next component in the flow.

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Choice router finds the FIRST true condition, then distribute the event to the ONE matched route.

MuleSoft Doc Ref : https://docs.mulesoft.com/mule-runtime/4.1/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: Response body: "Error" Default response status code: 200.

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1) Payload is successfully set to “Success – Started Flow”

2) When HTTP Request throws an error, execution halts

#[error.description] = “ABC"

#[error.errorType] = "XYZ"

3) The On Error Continue scope handles the error. When On Error Continue scope is invoked, all the processors in error block are executed and success response is sent back to the client with payload which is set in error flow. In this case payload is set to "Error" value in error block.

4) “Error” is returned to the requestor in the body of the HTTP request with HTTP Status Code: 200 as On error continue always sends success error code.

Reference Diagram:

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Correct answer is Mule runtime

DataWeave is the MuleSoft expression language for accessing and transforming data that travels through a Mule app. DataWeave is tightly integrated with the Mule runtime engine, which runs the scripts and expressions in your Mule app.

Mule Doc Reference : https://docs.mulesoft.com/mule-runtime/4.3/dataweave

Sequence can be described as follows.

* When web client sends the request , it sends payload as Blue (mentioned in question)

* In first iteration this will go to default choice , which sets payload to Red

* Via default route , flow will call itself with payload as Red

* In second iteration , as payload is Red , it will go to first route in choice router which will set payload to Blk and second iteration will end returning back payload as Blk to first iteration.

* This Blk will be again set to payload and first iteration will end returning back response as Blk

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Here’s specifically what is happening here:

1) Payload is successfully set to “Before”

2) Is null validation is used which will pass the message only if payload is null. In this case as payload is not null, it creates an Error Object. Flow execution stops

#[error.description] = “Validation error”

3) Because no error handler is defined, the Mule default error handler handles the error

4) “Validation error” 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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Below are the Key performance indicators (KPIs), to measure and track the and success of the C4E and its activities, as well as the growth and health of the application network. Most of the metrics can be extracted automatically, through REST APIs, from Anypoint Platform.

• # of assets published to Anypoint Exchange

• # of interactions with Anypoint Exchange assets

• # of APIs managed by Anypoint Platform

• # of System APIs managed by Anypoint Platform

• # of API clients registered for access to APIs

• # of API implementations deployed to Anypoint Platform

• # of API invocations

• # or fraction of lines of code covered by automated tests in CI/CD pipeline

• Ratio of info/warning/critical alerts to number of API invocations

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

Correct answer is Patients from year 2021.

The thing to note here is that year is not a query parameter and not the uri parameter. Hence it will filter all the patients and return the ones for whom year is 2021

Publish consume: Synchronous. Publish: Asynchronous.

URI parameter (Path Param) is basically used to identify a specific resource or resources . For eg : the URL to get employee details on the basis of employeeID will be GET /employees/{employeeID} where employees is resource and {employeeID} is URI parameter. Hence option 1is the correct answer

Correct answer is */status as it is the correct way to use wildcards while configuring path value in HTTP listener

This is a trcik question. On complete phase pyalod consists of summary of records processed which gives insight on which records failed or passed. Hence option 4 is correct answer

MuleSoft Documentation Reference : https://docs.mulesoft.com/mule-runtime/4.3/batch-processing-concept#on-complete

Correct answer is String is not blank.

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Here’s specifically what is happening here:

1) Payload is successfully set to “Start”

2) The Is Blank String validator creates an Error Object because the payload is string "Start". Execution stops

#[error.description] = “String is not blank”

3) Because no error handler is defined, the Mule default error handler handles the error. Remember, at its heart, the Mule Default Error handler is an error handling scope with just an on error propagate

4) “String is not blank” is the error message returned to the requestor in the body of the HTTP requestHTTP Status Code: 500

Reference Diagram:

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Correct answer is A global element

When we create a configuration file , that file needs to added as Global Configuration file in Global element. A global element is a reusable object containing parameters that any number of elements in a flow can share. You reference a global element from Anypoint Connectors or components in your Mule application

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

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 /accounts?account_type=retail&industry=finance

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.

Correct answer is 8 as events are processed in parallel in case of scatter gather router

The HTTP 415 Unsupported Media Type client error response code indicates that the server refuses to accept the request because the payload format is in an unsupported format. The format problem might be due to the request's indicated Content-Type or Content-Encoding , or as a result of inspecting the data directly. As per RAML input is expected in application/xml.

Hence correct answer is Set a request header with the name Content-Type to a

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. Hence correct answer is option 2

APIKIt Creates a separate flow for each HTTP method

Option1 is correct syntax to configure HTTP Listener endpoint

Correct answer is API manager

Error in validation component will get processed by Processer level On Error Propagate block and then error will be rethrown which will get processed by flow level error handler which will set payload to "Error- main flow". Hence correct answer is Error - main flow

1) Request is received by HTTP listener

2) Try scope gets executed

3) The validator component in the Try scope creates an Error Object because the payload is not null.

4) The On Error Propagate handles the error. The payload is set to “Error – Try scope”

6) “Error – Try scope” is returned to the 'On Error Continue' block. Main flow execution stops. Payload is set to "Error - main flow"

7) “Error - main flow” is returned to the requestor in the body of the HTTP request. HTTP Status Code: 200

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Reference Diagram though not exactly same, conditions are similar. They will help you answer any new question on error handling in real exam:

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https://docs.mulesoft.com/mule-runtime/4.3/on-error-scope-concept#on-error-continue

Correct answer is Products

Modern API has three features 1) Treated as products for easy consumption 2) Discoverable and accessible through self-service 3) Easily managed for security , scalability and performance

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

option 3 is the correct syntz to access application properties

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

* RAML file contains lot of information that could be considered as "not API-describing". Sort of "economy-class" members.

Equally important, but not necessarily part of the main RAML file.

* Through !includes, RAML allows us to build file-distributed API definitions, which is not only useful to encourage code reuse but also improves readability.

* We can create RAML fragments with such code and then include them in main RAML project using !include like:

types:

Book: !include bookDataType.raml and

examples:

input: !include bookExample.raml

* Additionally for

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Correct Answer: D

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

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

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

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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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

As dependency is not present in Mulesoft Maven repository, we need to install the dependency on computer's local Maven repository.

https://docs.mulesoft.com/mule-runtime/4.3/maven-reference

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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To include property. To keep the API definition concise, you can include external content, such as documentation, schemas, and frequently used patterns outside the definition itself. The parser interprets !include as if the content of the externally-hosted file or a URL were declared in-line.

To use the fragments in RAML you have to include the exact path(copy the path) of that fragment you want to use as shown below

Option 3 is the correct as correct syntax is

examples: !include examples/StudentExample.raml