MB-820 Microsoft Dynamics 365 Business Central Developer (beta) Question and Answers

To roll back changes to a test method after run time, you should:

• Set the TransactionModel attribute to AutoRollback.

To run an approve action on a test page named TestPageA, you should:

• Configure TestPageA.Approve.Invoke().

In Business Central's testing framework, the TransactionModel attribute can be set to AutoRollback. This ensures that any changes made during the test are rolled back after the test is complete, leaving the database in its original state.

For running an action on a test page, you would use the 'Invoke' method on the action you wish to perform. In this case, to run an approve action on TestPageA, you would use TestPageA.Approve.Invoke() within your test codeunit. This simulates the user action of approving something on the page.

These actions ensure that the testing environment is properly set up to test specific functionalities without persisting test data and to invoke actions as part of the test scenarios.

For the data integrity requirements, the table field properties to use are:

• To establish lookups into other records, use the TableRelation property.
• To validate if a record exists in a destination record, use the ValidateTableRelation property.

In Business Central, when creating tables to hold data, maintaining data integrity is crucial:

• TableRelation Property:This property is used to create a relationship between the field in one table and a field in another table, which is typically used for lookups. When you set the TableRelation property on a field, it allows users to select from a list of values that exist in the related table.
• ValidateTableRelation Property:This property is used to ensure that the value entered in a field matches one of the values in a related table. If a user tries to enter a value that doesn't exist in the related table, an error will occur.

Using InherentPermissions in an event subscriber with the specified syntax could potentially resolve the permission issues related to MyTable, provided that the permissions specified (in this case, 'R' for Read) align with the minimum necessary for the users to perform their tasks. This approach allows the app to grant permissions dynamically based on the context of the event subscriber, which in this case is involved with inserting data into MyTable. By granting Read permission at the event level, it ensures that users have the necessary permissions to interact with MyTable in the context of the operations facilitated by the event subscriber, without needing to alter existing permission sets or grant broader permissions than necessary. This solution adheres to the principle of least privilege by ensuring that permissions are granted only within the narrow scope needed for specific operations, thereby potentially resolving the reported user issues in a secure and controlled manner.

In Business Central, fields in tables are assigned specific data types that determine the kind of data they can store. For the Non-conformity table mentioned in the case study, the following data types should be used:

• Date for the Non-Conformity Date field: This is because the Non-conformity Date field is required to store only the date when the non-conformity was recorded. The Date data type is appropriate for storing dates without times.
• Code for the Non-Conformity Number field: The Non-conformity Number field is described to use alphanumeric values with a format that includes "NC" and the year, like "NC24-001". In Business Central, the Code data type is used for fields that store alphanumeric keys. It is a text field with a limited length, which makes it suitable for number series that contain letters and numbers.

Other options are not suitable:

• A. Integer for the Non-conformity Number field: This would not be appropriate because the Non-conformity Number includes alphanumeric characters and not just integers.
• B. DateTime for the Non-Conformity Date field: This is not correct because there is no requirement to store the time alongside the date.
• C. Char for the Non-Conformity Number field: Char data type is not typically used in Business Central for number series or identifiers. The Code data type is preferred for this purpose.

codeunit 52102 "POS API Management"

{

Access = Public;

Permissions = TableData "POS Information" = rwdx;

trigger OnRun()

begin

readAPI();

end;

procedure readAPI()

begin

// Your code here to read from the POS API

end;

}

For the Install codeunit required for the extension used for installing or updating the Housekeeping app, you should use the following data type and declaration:

• Data type for information: ModuleInfo
• Start of the declaration of the method or procedure to perform the tasks: local procedure

In AL language, which is used for developing extensions in Business Central, an Install codeunit is a special type of codeunit that is used to handle installation or upgrade logic for an extension.

• ModuleInfo is a data type that contains information about the current extension, such as its version. It is typically used within the OnInstallAppPerCompany or OnUpgradePerCompany triggers of an Install codeunit to determine if the app is being installed for the first time or upgraded.
• A local procedure within an Install codeunit is a method that is only accessible within the codeunit itself. It is not visible to other objects or extensions. This is suitable for tasks that are internal to the installation process and should not be exposed globally.

These selections align with the requirements of handling installation and update procedures in a controlled and encapsulated manner within Business Central extensions.

For the requirements provided, the appropriate page types should be selected as follows:

• Display relevant insights in the Housekeeping Role Center: HeadlinePart
• Display the additional information for the Room table: FactBox
• Configure the first installation: StandardDialog

Comprehensive Detailed ExplanationIn the context of Microsoft Dynamics 365 Business Central, page types are crucial for determining how information is presented to the user.

• HeadlinePart: This page type is designed to display key data and insights in a concise and visually appealing manner, often used in Role Centers to highlight important information. It is suitable for the Housekeeping Role Center to display relevant insights.
• FactBox: This page type is used to display supplementary information related to a selected record in the main part of the page. It's often used to show additional details about a record in a list, card, or document page. In this scenario, it is suitable for showing additional information about a specific Room when viewing the Room table.
• StandardDialog: This is a page type that provides a modal dialog for user interaction, commonly used for setup wizards, confirmations, and input forms that require user action before proceeding. This is appropriate for configuring the first installation, where a step-by-step guided interaction is necessary.

var

TempBlob: Codeunit "Temp Blob";

IncidentOutStream: OutStream;

IncidentInStream: InStream;

ImageFilter, FileName: Text;

begin

// Initialize the TempBlob and streams

TempBlob.CreateOutStream(IncidentOutStream);

Rec.Image.ExportStream(IncidentOutStream); // 'Rec' refers to the current Room Incident record

TempBlob.CreateInStream(IncidentInStream);

// Set the filters and filename for the image

ImageFilter := 'Image Files (*.bmp,*.jpg,*.jpeg,*.gif)|*.bmp;*.jpg;*.jpeg;*.gif';

FileName := 'Customer Picture';

// Prompt the user to download the image

if not DownloadFromStream(IncidentInStream, '', 'Download Incident Picture', '', ImageFilter, FileName) then

Error('Unable to download the image.');

end;

To correctly write the code to call the subcontractor's REST API, you would need to set the Authorization header with the base64 encoded username and password for basic authentication. The code segment indicates the use of the Base64Convert codeunit to convert the username and password to base64 format, which is then prefixed with "Basic " to form the proper Authorization header value.

The correct method to add the Authorization header to the RequestHeaders would be:

RequestHeaders.Add('Authorization', 'Basic ' + Base64Convert.ToBase64(Username + ':' + Password));

And the correct method to set the httpContent with the body of the request would be:

httpContent.WriteFrom(Body);

These are the necessary steps to form a well-structured HTTP request for basic authentication and to include the body of the request in the API call.

The task is to identify unwanted incoming web service calls during the last seven days. To do this, we need to look at KQL (Kusto Query Language) queries that would filter out web service calls based on the timestamp (to ensure the calls are within the last seven days) and by certain characteristics that would indicate they are unwanted, such as the wrong type of protocol (SOAP in this case, as Contoso Ltd. plans to dismiss using it).

Looking at the options:

• Option A: This query selects all traces where the timestamp is within the last 7 days and where the custom dimension has a value of 'RT0008', and where the category is either 'ODataV4', 'ODataV3', or 'Api'. This query would show all API calls except SOAP, so it does not directly answer the question about unwanted calls.
• Option B: This query filters for traces with a timestamp within the last 7 days, where 'RT0008' is present, and specifically looks for the category 'SOAP'. This query is correct because it directly targets SOAP calls, which are the unwanted calls according to Contoso Ltd.'s plans.
• Option C: Similar to option B, this query filters for traces within the last 7 days and looks for 'RT0008' but uses the equality operator for the category 'SOAP'. This would also correctly return the unwanted SOAP calls.
• Option D: This query also filters for traces within the last 7 days, but it excludes the 'ODataV4' category, which doesn't necessarily target the unwanted SOAP calls.
• Option E: This query selects traces where the timestamp is within the last 7 days and the custom dimension has 'RT0008'. However, it filters out categories 'ODataV4' and 'Api', which does not directly help in identifying the unwanted SOAP calls.

Therefore, the queries that should be used to determine if there are unwanted incoming web service calls (SOAP calls) in the tenant during the last seven days are Options B and C. These queries are specific to identifying SOAP protocol usage, which is what Contoso Ltd. considers unwanted.

In the context provided by the case study, when calling an API action from a mobile application, the correct format for a POST request to an action in Business Central typically involves specifying the entity (/issues), the ID of the entity (88122e0e-5796-ec11-bb87-000d3a392eb5), and the action to be called (/Copy). The action name should match the exact name as defined in the AL code, which is case-sensitive.

• Option A is incorrect because it uses a non-standard format for the action call.
• Option B uses the PATCH method, which is generally used for update operations, not for calling actions.
• Option C is correct as it uses the POST method, which is appropriate for calling actions, and correctly specifies the entity, ID, and action name.
• Option D is incorrect because the action name /copy is in lowercase, while AL is case-sensitive, and it should match the case exactly as defined in the code.
• Option E incorrectly adds 'MicrosoftNAV' before the action name, which is not standard for calling actions in Business Central APIs.

Hence, the correct action to use when calling the Issue API action from the mobile application is given in Option C.