AI Interview Backend

A production-ready .NET 10 backend for an AI-powered interview platform. Features resume analysis, mock AI interviews, job management, and company profiles — powered by Groq (primary) with Ollama as a local fallback.

---

🚀 Quick Links

• Deployment Guide: See DEPLOYMENT.md for production setup
• API Documentation: Swagger UI available at /swagger endpoint
• Environment Setup: Copy appsettings.Development.json.example and configure with your values

---

Tech Stack

• .NET 10 / ASP.NET Core Web API
• PostgreSQL + Dapper
• ASP.NET Core Identity + JWT Authentication
• Groq API (llama-3.1-8b-instant) — primary AI
• Ollama (http://localhost:11434) — local AI fallback
• Clean layered architecture: Core → Application → Infrastructure → Server
• Docker & Docker Compose support
• Email templates with HTML formatting

---

Project Structure

├── AIInterview.Core/           # DTOs, constants, shared models
├── AIInterview.Application/    # Interfaces, services, business logic
├── AIInterview.Infrastructure/ # Dapper repositories, DbContext, migrations
├── AIInterview.Server/         # Controllers, middleware, configuration
├── Templates/                  # Email templates (HTML)
├── docker-compose.yml          # Development compose
├── docker-compose.prod.yml     # Production compose
├── DEPLOYMENT.md               # Production deployment guide
└── deploy.sh / deploy.bat      # Deployment automation scripts

---

🔧 Getting Started (Local Development)

Prerequisites

• .NET 10 SDK (download)
• PostgreSQL 15+ (download)
• (Optional) Docker & Docker Compose for containerized development
• (Optional) Ollama for local AI fallback (download)

1. Clone Repository

git clone <repo-url>
cd AIInterview.Server

2. Configure Environment

Option A: Manual Setup

Copy and edit configuration:

cd AIInterview.Server
cp appsettings.Development.json.example appsettings.Development.json
# Edit appsettings.Development.json with your values

Option B: Docker Setup

Use the development docker-compose:

docker-compose up -d
# This starts PostgreSQL, Ollama, and configures the database

3. Configure appsettings.Development.json

Update these required values:

{
  "ConnectionStrings": {
    "Default": "Host=localhost;Port=5432;Database=AI_Db;Username=postgres;Password=YOUR_PASSWORD"
  },
  "Jwt": {
    "SecretKey": "YourSecretKeyWithAtLeast32CharactersForDevelopment"
  },
  "Google": {
    "ClientId": "your-google-oauth-client-id.apps.googleusercontent.com"
  },
  "Groq": {
    "ApiKey": "your-groq-api-key"
  },
  "CloudinarySettings": {
    "CloudName": "your-cloudinary-cloud-name",
    "ApiKey": "your-cloudinary-api-key",
    "ApiSecret": "your-cloudinary-api-secret"
  },
  "EmailSettings": {
    "Username": "your-email@gmail.com",
    "Password": "your-app-specific-password"
  }
}

API Keys & Credentials:

• Groq API: Get free key at https://console.groq.com
• Google OAuth: Set up at https://console.cloud.google.com
• Cloudinary: Sign up at https://cloudinary.com
• Gmail App Password: Enable 2FA and generate at https://myaccount.google.com/apppasswords

4. Run Database Migrations

# Apply migrations using EF Core
dotnet ef database update --project AIInterview.Infrastructure --startup-project AIInterview.Server

5. Run the Server

dotnet run --project AIInterview.Server

Endpoints:

• API: https://localhost:7129
• Swagger UI: https://localhost:7129/swagger
• Health Check: https://localhost:7129/health

---

📧 Email Template

Forgot-password emails use HTML template from Templates/ForgotPasswordTemplate.html with dynamic placeholders:

• {{USER_EMAIL}} — User's email address
• {{RESET_URL}} — Password reset link
• {{RESET_CODE}} — Short reset reference code shown in email

Edit the template to customize styling and content.

---

AI Architecture

Request
  └── FallbackAiService
        ├── GroqAiService (primary)   — api.groq.com
        └── OllamaAiService (fallback) — localhost:11434

If Groq fails for any reason (rate limit, network, etc.), the request automatically retries via Ollama. No code changes needed.

Ollama Setup (optional but recommended)

# Install from https://ollama.com
ollama serve
ollama pull llama3.2

---

API Endpoints

All endpoints require Authorization: Bearer <token> unless marked public.

Auth — /api/account

Method	Endpoint	Description	Auth
POST	/api/account/register	Register new user	Public
POST	/api/account/login	Login, returns JWT	Public
POST	/api/account/refresh	Refresh access token	Public
POST	/api/account/google-login	Google OAuth login	Public
POST	/api/account/logout	Logout	Required

Identity Password Policy

• Minimum length: 6 characters
• No required digit
• No required lowercase
• No required uppercase
• No required special character

Job Seeker — /api/jobseeker

Method	Endpoint	Description
GET	/api/jobseeker/profile	Get profile
PUT	/api/jobseeker/profile	Create or update profile
POST	/api/jobseeker/upload-avatar	Upload avatar image
DELETE	/api/jobseeker/delete-avatar	Delete avatar
POST	/api/jobseeker/upload-resume	Upload resume (PDF/DOCX)
DELETE	/api/jobseeker/delete-resume	Delete resume
GET	/api/jobseeker/download-resume	Download resume
GET	/api/jobseeker/experience	Get work experience
POST	/api/jobseeker/experience	Add experience
PUT	/api/jobseeker/experience/{id}	Update experience
DELETE	/api/jobseeker/experience/{id}	Delete experience
GET	/api/jobseeker/education	Get education
POST	/api/jobseeker/education	Add education
PUT	/api/jobseeker/education/{id}	Update education
DELETE	/api/jobseeker/education/{id}	Delete education
GET	/api/jobseeker/skills	Get user skills
PUT	/api/jobseeker/skills	Sync skills

Resume Enhancer — /api/resume-enhancer

Method	Endpoint	Description
POST	/api/resume-enhancer/analyze	Analyze uploaded resume file
POST	/api/resume-enhancer/analyze-from-profile	Analyze resume from profile
GET	/api/resume-enhancer/result	Get last cached analysis

Mock Interview — /api/mock-interview

Method	Endpoint	Description
POST	/api/mock-interview/start	Start new interview session
POST	/api/mock-interview/message	Send answer, get next question
GET	/api/mock-interview/session/{sessionId}	Get session with full chat history
GET	/api/mock-interview/sessions	Get all sessions for current user

Start interview — request:

{
  "skills": ["React", "TypeScript"]
}

If skills is empty or omitted, skills are loaded from the user's profile automatically.

Start interview — response:

{
  "sessionId": "abc-123...",
  "skills": ["React", "TypeScript"],
  "firstQuestion": "Can you explain the difference between props and state in React?"
}

Send message — request:

{
  "sessionId": "abc-123...",
  "userMessage": "Props are read-only and passed from parent, state is managed internally."
}

Send message — response:

{
  "aiMessage": "Good answer! Next question: How does the useEffect hook work?",
  "isCompleted": false,
  "feedbackSummary": null
}

After 5 questions isCompleted becomes true and feedbackSummary contains the overall performance summary.

Jobs — /api/jobs

Method	Endpoint	Description
GET	/api/jobs/my-jobs	Get employer's posted jobs
POST	/api/jobs	Create job posting
PUT	/api/jobs/{id}	Update job
DELETE	/api/jobs/{id}	Delete job
PATCH	/api/jobs/{id}/close	Close job
PATCH	/api/jobs/{id}/reopen	Reopen job
GET	/api/jobs/{id}/applicants	Get applicants
POST	/api/jobs/generate-description	AI-generate job description

Generate description — request:

{
  "title": "Frontend Developer",
  "skills": ["React", "TypeScript", "Redux"]
}

Company Profile — /api/companyprofile

Method	Endpoint	Description
GET	/api/companyprofile	Get company profile
PUT	/api/companyprofile	Update company profile
POST	/api/companyprofile/upload-logo	Upload company logo

Lookups — /api/lookup

Method	Endpoint	Description	Auth
GET	/api/lookup/skills	Get all available skills	Public
GET	/api/lookup/job-types	Get job types	Public
GET	/api/lookup/company-sizes	Get company sizes	Public

---

Environment Variables Reference

Key	Description
ConnectionStrings:Default	PostgreSQL connection string
Jwt:SecretKey	JWT signing key (min 32 chars)
Jwt:Issuer	JWT issuer
Jwt:Audience	JWT audience
Jwt:AccessTokenExpiration	Access token TTL in minutes
Jwt:RefreshTokenExpiration	Refresh token TTL in minutes
Google:ClientId	Google OAuth client ID
Groq:ApiKey	Groq API key (console.groq.com)
Ollama:BaseUrl	Ollama base URL (default: http://localhost:11434)
Ollama:Model	Ollama model name (default: llama3.2)
CloudinarySettings:CloudName	Cloudinary cloud name
CloudinarySettings:ApiKey	Cloudinary API key
CloudinarySettings:ApiSecret	Cloudinary API secret
Cors:AllowedOrigins	Array of allowed frontend origins