This software guidebook provides an overview of the DevInterview application. It includes a summary of the following:
- The requirements, constraints and principles behind the solution.
- The software architecture, including the high-level technology choices and structure of the software.
- The infrastructure architecture and how the software is deployed.
- Operational and support aspects of the application.
DevInterview is an application designed to assist software developers in preparing for technical interviews or certification exams through questions with respective detailed answers.
The tool has three types of user:
- Anonymous: Anybody with a web browser o smartphone can view free content on the application.
- Student: Authenticated user
- Admin: People with administrative (super-user) access to the Administration Panel can manage the content that is aggregated into the application.
There are three types of systems that DevInterview integrates with.
- OpenAI API: Understand or generate natural language, code, or images.
- SMTP Server: Google e-mail system.
- Firebase Cloud Messaging: Google's cross platform push notifications.
- Google Play Billing: Google's payment system for in-app purchases and subscriptions on Android apps.
- As an anonymous user, I want to be able to access the homepage to explore available content.
- As an anonymous user, I want to be able to view a list of available categories or topics to filter interview questions.
- As an anonymous user, I want the option to register for an account to access additional features.
- As a Student, I want to be able to log in to my account to access personalized features.
- As a Student, I want the option to update my profile information, such as my email address or password.
- As a Student, I want to be able to browse the interview question catalog to explore different areas of knowledge.
- As a Student, I want to be able to search for specific questions by topic or keyword to quickly find what I need.
- As a Student, I want the option to mark questions as resolved once I have reviewed them.
- As a Student, I want to be able to bookmark questions for later review.
- As a Student, I want to receive notifications about important system updates or newly added questions.
- As a Student, I want to have access to additional resources such as articles, tutorials, or code examples related to interview questions.
- As a Student, I want to have the option to provide feedback on the usefulness and quality of questions and answers to help improve the system.
- As an administrator, I want the ability to add new interview questions to the catalog to expand and keep the content up-to-date.
- As an administrator, I want to be able to edit or delete existing questions in the catalog to correct errors or update information as needed.
- As an administrator, I want to be able to manage the tags or categories associated with questions to ensure consistent organization and facilitate user search.
- As an administrator, I want the ability to send notifications to users about important system updates or new features available.
- As an administrator, I want to be able to manage user accounts, including the ability to create, edit, or delete accounts as needed.
- As an administrator, I want the ability to customize the appearance and settings of the system, including the ability to change the theme, add custom logos, and adjust privacy settings.
This section provides information about the desired quality attributes (non-functional requirements) of the application.
All pages on DevInterview should load and render in under five seconds, for fifty concurrent users.
All authentication must be done via a third-party mechanism such as Twitter, Facebook or Google.
All user interface text will be presented in English only.
The application should work consistently across the following browsers:
- Chrome
- Edge
- Firefox
- Safari
This section provides information about the constraints imposed on the development of the DevInterview application.
Since there is no formal budget for the DevInterview application, there is a constraint to use free and open source technologies for the development. Ideally, the application should run on a single server with hosting costs of less than 20 USD per month.
This section provides information about the principles adopted for the development of the DevInterview application.
The strategy for automated testing is to use automated unit and component tests.
- Unit tests: These are fast running, very small tests that operate on a single class or method in isolation.
- Component tests: Rather than mocking out database connections to test component internals, components are tested as single units to avoid breaking encapsulation.
All configuration needed by components is externalised into a configuration file, which is held outside of the deployment files created by the build process. This means that builds can be migrated from development, testing and into production without change.
- Logging Framework for .NET: Serilog
- Use an optimal structured log format: By using a structured log with an optimal format, developers ensure that log data is readable, uniform, and easily searchable.
2023-03-07T12:15:30+00:00 [INFO] PaymentService - Payment processed successfully for Order #12345
- Do NOT log sensitive information: API keys, passwords, credentials and more fall under this category. It's far to risky to log anything sensitive as it increases the chances of it leaking and becoming a security problem
❌
logger.error("Unable to log in", {request});
✅
logger.error("Unable to log in", {
username: request.user,
password: request.pass ? "[HIDDEN]" : null,
// any additional context needed?
})
- Be specific in your messages: Logging is only as beneficial as the message in the log, therefor, be specific.
❌
logger.info("We're starting!")
...
logger.info("task complete!")
✅
logger.info("Starting task", {
name: taskName,
params: params,
startTime: startTime
});
logger.info("task complete", {
response: output.response,
event: {
action: taskName,
duration: currentTime - startTime
}
})
- Log all errors: Logs are a best friend to those debugging, so, as a programmer if you find yourself in a situation writing error handling, make sure you always log the error before throwing a different one for the user. If we don't log the original error then we could find ourselves with no context as too why we're throwing a
SystemError.
catch(err)
{
logger.error('An error occured', {error: err, args: args});
throw new SystemError('Unable to process request');
}
This section provides an overview of the DevInterview software architecture.
The following diagram shows the logical containers that make up the DevInterview application. The diagram does not represent the physical number and location of containers - please see the infrastructure and deployment sections for this information.
- Admin Panel WebApp: An admin panel serves as a user-friendly control center to maintain various aspects of your web application like managing and organising content, tracking website analytics, managing user accounts, and performing various other tasks.
- DevInterview SPA: ...
- Web-DevInterview API Gateway: ...
- Mobile-DevInterview API Gateway: ...
- Identity Service: User authentication service based on JWT, with SQL Server database.
- Catalog Service: Catalog service of questions and answers for interviews and certification exams.
- Students Service: ...
This section provides information about the infrastructure architecture of the DevInterview application.
This section provides information about the mapping between the software architecture and the infrastructure architecture. We use a deployment diagram to illustrate how instances of software systems and/or containers in the static model are deployed on to the infrastructure within a given deployment environment (e.g. production, staging, development, etc).
docker-compose -f docker-compose.yml -f docker-compose.override.yml up -d
Get data with Cloud Firestore https://firebase.google.com/docs/firestore/query-data/get-data#c
Upload Files Firebase Storage:
- Install FirebaseStore.net
- Activar servicio Storage en Firebase
- Get the "Folder Path" --> gs://devinterview-2aedb.appspot.com and set variable "Bucket"
- Get the "Web Api Key" --> Project Settings
- Create user for authentication: uploadfiles@devinterview.com
- Change Storage Rules: allow read, write: if request.auth != null;
- https://www.youtube.com/watch?v=tDBqEimGcDo https://dev.to/airarrazabald/conectando-api-en-net-5-con-firebase-storage-2fhk