Case Study 6 - Contoso, Ltd
Background
Overview
You are a developer for Contoso, Ltd. The company has a social networking website that is developed as a Single Page Application (SPA). The main web application for the social networking website loads user uploaded content from blob storage.
You are developing a solution to monitor uploaded data for inappropriate content. The following process occurs when users upload content by using the SPA:
* Messages are sent to ContentUploadService.
* Content is processed by ContentAnalysisService.
* After processing is complete, the content is posted to the social network or a rejection message
is posted in its place.
The ContentAnalysisService is deployed with Azure Container Instances from a private Azure Container Registry named contosoimages.
The solution will use eight CPU cores.
Azure Active Directory
Contoso, Ltd. uses Azure Active Directory (Azure AD) for both internal and guest accounts.
Requirements
ContentAnalysisService
The company's data science group built ContentAnalysisService which accepts user generated content as a string and returns a probable value for inappropriate content. Any values over a specific threshold must be reviewed by an employee of Contoso, Ltd.
You must create an Azure Function named CheckUserContent to perform the content checks.
Costs
You must minimize costs for all Azure services.
Manual review
To review content, the user must authenticate to the website portion of the ContentAnalysisService using their Azure AD credentials. The website is built using React and all pages and API endpoints require authentication. In order to review content a user must be part of a ContentReviewer role. All completed reviews must include the reviewer's email address for auditing purposes.
High availability
All services must run in multiple regions. The failure of any service in a region must not impact overall application availability.
Monitoring
An alert must be raised if the ContentUploadService uses more than 80 percent of available CPU cores.
Security
You have the following security requirements:
* Any web service accessible over the Internet must be protected from cross site scripting
attacks.
* All websites and services must use SSL from a valid root certificate authority.
* Azure Storage access keys must only be stored in memory and must be available only to the
service.
* All Internal services must only be accessible from internal Virtual Networks (VNets).
* All parts of the system must support inbound and outbound traffic restrictions.
* All service calls must be authenticated by using Azure AD.
User agreements
When a user submits content, they must agree to a user agreement. The agreement allows employees of Contoso, Ltd. to review content, store cookies on user devices, and track user's IP addresses.
Information regarding agreements is used by multiple divisions within Contoso, Ltd.
User responses must not be lost and must be available to all parties regardless of individual service uptime. The volume of agreements is expected to be in the millions per hour.
Validation testing
When a new version of the ContentAnalysisService is available the previous seven days of content must be processed with the new version to verify that the new version does not significantly deviate from the old version.
Issues
Users of the ContentUploadService report that they occasionally see HTTP 502 responses on specific pages.
Code
ContentUploadService

ApplicationManifest

Hotspot Question
You need to ensure that network security policies are met.
How should you configure network security? To answer, select the appropriate options in the answer area.
NOTE: Each correct selection is worth one point.

You have an Azure subscription that contains an Application Insights resource named AI1 and an Azure App Service web app named App1.
You create a Standard availability test in AI1. You set its URL to point to App1.
You need to ensure that any failed tests generate email notifications to the owners of the subscription.
What should you do?

• A. Enable the test.
• B. Enable the alert.
• C. Create an action group.
• D. Create an alert rule.

You are developing several Azure API Management (APIM) hosted APIs.
You must make several minor and non-breaking changes to one of the APIs. The API changes include the following requirements:
- Must not disrupt callers of the API.
- Enable roll back if you find issues.
- Documented to enable developers to understand what is new.
- Tested before publishing.
You need to update the API.
What should you do?

• A. Create and publish a product.
• B. Configure and apply header-based versioning.
• C. Add a new revision to the API.
• D. Configure and apply query string-based versioning.
• E. Configure and apply a custom policy.

Case Study 7 - Proseware, Inc
Background
You are a developer for Proseware, Inc. You are developing an application that applies a set of governance policies for Proseware's internal services, external services, and applications. The application will also provide a shared library for common functionality.
Requirements
Policy service
You develop and deploy a stateful ASP.NET Core 2.1 web application named Policy service to an Azure App Service Web App. The application reacts to events from Azure Event Grid and performs policy actions based on those events.
The application must include the Event Grid Event ID field in all Application Insights telemetry.
Policy service must use Application Insights to automatically scale with the number of policy actions that it is performing.
Policies
Log Policy
All Azure App Service Web Apps must write logs to Azure Blob storage. All log files should be saved to a container named logdrop. Logs must remain in the container for 15 days.
Authentication events
Authentication events are used to monitor users signing in and signing out. All authentication events must be processed by Policy service. Sign outs must be processed as quickly as possible.
PolicyLib
You have a shared library named PolicyLib that contains functionality common to all ASP.NET Core web services and applications. The PolicyLib library must:
* Exclude non-user actions from Application Insights telemetry.
* Provide methods that allow a web service to scale itself
* Ensure that scaling actions do not disrupt application usage
Other
Anomaly detection service
You have an anomaly detection service that analyzes log information for anomalies. It is implemented as an Azure Machine Learning model. The model is deployed as a web service.
If an anomaly is detected, an Azure Function that emails administrators is called by using an HTTP WebHook.
Health monitoring
All web applications and services have health monitoring at the /health service endpoint.
Policy loss
When you deploy Policy service, policies may not be applied if they were in the process of being applied during the deployment.
Performance issue
When under heavy load, the anomaly detection service undergoes slowdowns and rejects connections.
Notification latency
Users report that anomaly detection emails can sometimes arrive several minutes after an anomaly is detected.
Relevant portions of the app files are shown below. Line numbers are included for reference only and include a two-character prefix that denotes the specific file to which they belong.


Relevant portions of the app files are shown below. Line numbers are included for reference only and include a two-character prefix that denotes the specific file to which they belong.

Drag and Drop Question
You need to add code at line EG15 in EventGridController.cs to ensure that the Log policy applies to all services.
How should you complete the code? To answer, drag the appropriate code segments to the correct locations. Each code segment may be used once, more than once, or not at all. You may need to drag the split bar between panes or scroll to view content.
NOTE: Each correct selection is worth one point.

Case Study 3 - City Power & Light
Background
City Power & Light company provides electrical infrastructure monitoring solutions for homes and businesses. The company is migrating solutions to Azure.
Current environment
Architecture overview
The company has a public website located at http://www.cpandl.com/. The site is a single-page web application that runs in Azure App Service on Linux. The website uses files stored in Azure Storage and cached in Azure Content Delivery Network (CDN) to serve static content.
API Management and Azure Function App functions are used to process and store data in Azure Database for PostgreSQL. API Management is used to broker communications to the Azure Function app functions for Logic app integration. Logic apps are used to orchestrate the data processing while Service Bus and Event Grid handle messaging and events.
The solution uses Application Insights, Azure Monitor, and Azure Key Vault.
Architecture diagram
The company has several applications and services that support their business. The company plans to implement serverless computing where possible. The overall architecture is shown below.

User authentication
The following steps detail the user authentication process:
37.The user selects Sign in in the website.
38.The browser redirects the user to the Azure Active Directory (Azure AD) sign in page.
39.The user signs in.
40.Azure AD redirects the user's session back to the web application. The URL includes an access token.
41.The web application calls an API and includes the access token in the authentication header.
The application ID is sent as the audience ('aud') claim in the access token.
42.The back-end API validates the access token.
Requirements
Corporate website
* Communications and content must be secured by using SSL.
* Communications must use HTTPS.
* Data must be replicated to a secondary region and three availability zones.
* Data storage costs must be minimized.
Azure Database for PostgreSQL
The database connection string is stored in Azure Key Vault with the following attributes:
* Azure Key Vault name: cpandlkeyvault
* Secret name: PostgreSQLConn
* Id: 80df3e46ffcd4f1cb187f79905e9a1e8
The connection information is updated frequently. The application must always use the latest information to connect to the database.
Azure Service Bus and Azure Event Grid
* Azure Event Grid must use Azure Service Bus for queue-based load leveling.
* Events in Azure Event Grid must be routed directly to Service Bus queues for use in buffering.
* Events from Azure Service Bus and other Azure services must continue to be routed to Azure
Event Grid for processing.
Security
* All SSL certificates and credentials must be stored in Azure Key Vault.
* File access must restrict access by IP, protocol, and Azure AD rights.
* All user accounts and processes must receive only those privileges which are essential to
perform their intended function.
Compliance
Auditing of the file updates and transfers must be enabled to comply with General Data Protection Regulation (GDPR). The file updates must be read-only, stored in the order in which they occurred, include only create, update, delete, and copy operations, and be retained for compliance reasons.
Issues
Corporate website
While testing the site, the following error message displays:
CryptographicException: The system cannot find the file specified.
Function app
You perform local testing for the RequestUserApproval function. The following error message displays:
'Timeout value of 00:10:00 exceeded by function: RequestUserApproval'
The same error message displays when you test the function in an Azure development environment when you run the following Kusto query:
FunctionAppLogs
| where FunctionName = = "RequestUserApproval"
Logic app
You test the Logic app in a development environment. The following error message displays:
'400 Bad Request'
Troubleshooting of the error shows an HttpTrigger action to call the RequestUserApproval function.
Code
Corporate website
Security.cs:

Function app
RequestUserApproval.cs:

Hotspot Question
You need to configure API Management for authentication.
Which policy values should you use? To answer, select the appropriate options in the answer area.
NOTE: Each correct selection is worth one point.