Week 1 Worklog

Week 1 Objectives:

  • Kick off the myFit project — a full-stack fitness management application.
  • Initialize project repositories for both Backend (Spring Boot) and Frontend (React Native + Expo).
  • Set up the local development environment: Java 17, PostgreSQL via Docker, Node.js, Expo CLI.
  • Agree on overall system architecture, module breakdown, and technology stack with the team.

Tasks to be carried out this week:

Day Task Start Date Completion Date Reference Material
2 - Project kickoff: define scope, features, and MVP requirements
  + Core features: workout plans, nutrition tracking, body metrics, session logging		 01/06/2026 01/06/2026
3 - Initialize Backend project with Spring Boot 3 + Maven
  + Scaffold with spring-boot-starter-web, spring-data-jpa, spring-security
  + Configure pom.xml: Flyway, Lombok, jjwt 0.11.5, AWS SDK v1
  + Establish package structure: common/, config/, module/		 01/07/2026 01/07/2026 https://start.spring.io/
4 - Set up PostgreSQL locally with Docker Compose
  + Write docker-compose.yml with postgres:15 service
  + Configure application.properties: datasource, JPA ddl-auto=create-drop, Flyway
  + Create .env / .env.example pattern for secrets
- Define EntityBase @MappedSuperclass: id (UUID), createdAt, updatedAt		 01/08/2026 01/08/2026 https://docs.docker.com/compose/
4 - Initialize Frontend project: React Native + Expo ~54 with TypeScript ~5.9
  + Scaffold with npx create-expo-app --template
  + Configure tsconfig.json, babel.config.js, metro.config.js
  + Install and configure NativeWind v4 + tailwind.config.js		 01/08/2026 01/08/2026 https://docs.expo.dev/
5 - Design system entity-relationship diagram
  + Entities: UserProfile, Food, Meal, Exercise, WorkoutPlan, BodyMetric, Session, Image…
  + Agree on relationships and cardinalities
- Create uniform ApiResponse<T> envelope: code, message, result, timestamp, path		 01/09/2026 01/09/2026
6 - Set up Redux Toolkit store on Frontend
  + Install @reduxjs/toolkit, react-redux
  + Wire store/index.ts and app/providers.tsx into App.tsx
- Configure Axios client: base URL from EXPO_PUBLIC_BACKEND_API_URL
- Configure TanStack React Query v5 QueryClient		 01/10/2026 01/10/2026 https://redux-toolkit.js.org/

Week 1 Achievements:

  • Successfully bootstrapped both backend and frontend project skeletons running locally.
  • Backend (Spring Boot):
    • Project starts and connects to PostgreSQL via Docker Compose in one command (docker-compose up -d).
    • EntityBase with UUID primary key and audit timestamps ready for all entities.
    • ApiResponse<T> response envelope standardized across all future endpoints.
    • Maven build passes with zero compile errors.
  • Frontend (React Native + Expo):
    • App renders on Android emulator via npx expo start.
    • NativeWind v4 configured — TailwindCSS utility classes work in RN components.
    • Redux Toolkit store and React Query QueryClient wired via providers.tsx.
    • Axios client reads base URL from .env (EXPO_PUBLIC_BACKEND_API_URL=http://localhost:8080).
  • Docker Compose environment reproducible across team machines.
  • .env secret management pattern established — no hardcoded credentials in source.

My Personal AWS Lab Notes (Individual Learning):

Lab 000001 — AWS Account Setup and IAM Bootstrap

  • Created a new AWS account and immediately set up MFA on the root user to prevent unauthorized access.
  • Created an IAM user group (e.g., admin-group) with AdministratorAccess policy, then created an IAM user and added it to the group for daily work — the root account is never used for routine tasks.
  • Learned: root user should only be used for tasks that specifically require it (billing, support plan changes, account closure). All other work should be done via IAM users or roles.

Lab 000007 — AWS Budgets

  • Created four types of budget alerts: cost budget (alerts when spending exceeds a fixed dollar threshold), usage budget (alerts on specific service usage), reservation budget (tracks Reserved Instance utilization), and Saving Plans budget (tracks Saving Plan coverage).
  • Learned: budgets do not stop spending — they only alert. However, they are essential for catching runaway costs early and are recommended as a first-day setup for any account.

Lab 000009 — AWS Support Plans

  • Explored the AWS Support Center to understand available support tiers (Basic, Developer, Business, Enterprise).
  • Learned: Basic support is free and includes documentation, whitepapers, and Trusted Advisor core checks. Paid tiers add response time guarantees, Trusted Advisor full checks, and a TAM (Technical Account Manager) at Enterprise level.

Module 01-04 to 01-07 — AWS Global Infrastructure and Account Concepts

  • Availability Zones (AZs): Each AZ is one or more physical datacenters. AZs provide fault isolation — if one AZ fails, others remain operational. AWS recommends deploying across at least 2 AZs. Exam tip: minimum of 2 AZs required for high availability answers.
  • AWS Regions: Each region contains at least 3 AZs. There are 25+ regions globally, connected by AWS backbone network. Region selection depends on user geography, service availability per region, and cost (older regions tend to be cheaper).
  • Edge Locations: AWS CDN network nodes used by CloudFront (CDN), WAF (Web Application Firewall), and Route 53 (DNS). Edge locations serve cached content closer to end users.
  • IAM vs Root user: Root user = the original account email/password — never use for daily tasks. IAM users are sub-accounts with specific permissions. IAM groups simplify permission management across teams and reduce blast radius from compromised credentials.
  • Cost optimization levers: Reserved Instances (commit to 1–3 year term for up to 72% savings), Savings Plans (flexible commitment), Spot Instances (up to 90% cheaper but can be interrupted at any time — not suitable for critical workloads). Additional levers: auto-scaling to avoid idle capacity, serverless (pay only when running), tagging for cost allocation, and Architecture Review via Well-Architected Framework.

AWS Knowledge Summary (Concluded from Lab Notes):

  • Established a secure AWS account baseline by enforcing MFA, minimizing root-user usage, and delegating daily work to IAM identities.
  • Understood budgets and support plans as governance controls that improve cost visibility and response readiness, while not directly stopping spend.
  • Connected Region, AZ, and Edge Location concepts to real architecture decisions for availability, latency, and service placement.
  • Clarified IAM boundaries between root user, IAM users, and groups to reduce credential blast radius.
  • Identified major cloud cost levers (RI, Savings Plans, Spot, autoscaling, serverless, tagging) as design-time decisions.

Next Week Plan:

  • Backend: Integrate AWS Cognito — configure SecurityConfig with JWT resource server, write custom OAuth2TokenValidator, build UserProfile entity + UserProfileController with sync/CRUD endpoints.
  • Frontend: Implement the full Authentication flow — LoginScreen with PKCE OAuth via expo-auth-session, token storage in expo-secure-store, authSlice Redux state.