making the interview

kassett · kassett · commit 7bd9735713f0 · 2026-03-17T13:07:39.000-04:00
diff --git a/.github/workflows/docker-image.yml b/.github/workflows/docker-image.yml
@@ -0,0 +1,27 @@
+name: Build and Push Docker Image
+
+on:
+  push:
+    branches:
+      - main
+
+permissions:
+  contents: read
+  packages: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Log in to GitHub Container Registry
+        run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u "${{ github.actor }}" --password-stdin
+
+      - name: Build and push image
+        run: |
+          IMAGE_ID=ghcr.io/${{ github.repository }}
+          IMAGE_ID=$(echo "$IMAGE_ID" | tr '[:upper:]' '[:lower:]')
+          docker build -t "$IMAGE_ID:latest" .
+          docker push "$IMAGE_ID:latest"
diff --git a/Dockerfile b/Dockerfile
@@ -0,0 +1,21 @@
+FROM astral/uv:python3.12-trixie
+
+ENV PYTHONDONTWRITEBYTECODE=1 \
+    PYTHONUNBUFFERED=1
+
+WORKDIR /app
+
+COPY pyproject.toml uv.lock README.md ./
+COPY src ./src
+
+RUN uv sync --frozen --no-dev
+
+COPY entrypoints ./entrypoints
+RUN chmod +x entrypoints/*.sh
+
+ENV VIRTUAL_ENV=/app/.venv
+ENV PATH=/app/.venv/bin:$PATH
+ENV PYTHONPATH=/app/src
+
+ENTRYPOINT ["/app/entrypoints/docker-entrypoint.sh"]
+CMD ["api"]
diff --git a/Makefile b/Makefile
@@ -0,0 +1,4 @@
+
+provision:
+	minkube start
+	find manifests -name '*.yaml' -print0 | xargs -0 -n1 kubectl apply -f
diff --git a/README.md b/README.md
@@ -1 +1,15 @@
 # devops-interview
+
+## Setup
+
+To start up the development environment, you will run `make provision`.
+
+## Assignment
+Using the provided Docker image, write a Helm chart that deploys both the FastAPI server and Celery
+worker. The chart should launch:
+
+- An API workload that runs the container with the `api` entrypoint (equivalent to `docker run <image> api`).
+- A worker workload that runs the container with the `celery` entrypoint (`docker run <image> celery`).
+
+Your Helm definitions should set any required environment variables (Redis/Postgres details, queue
+names, etc.) and expose the FastAPI service appropriately.
diff --git a/entrypoints/api.sh b/entrypoints/api.sh
@@ -0,0 +1,4 @@
+#!/bin/bash
+set -euo pipefail
+
+exec uvicorn interview.api:app --host 0.0.0.0 --port 5000 --workers 2 "$@"
diff --git a/entrypoints/celery.sh b/entrypoints/celery.sh
@@ -0,0 +1,4 @@
+#!/bin/bash
+set -euo pipefail
+
+exec celery -A interview.worker worker --concurrency 1 --queues default "$@"
diff --git a/entrypoints/docker-entrypoint.sh b/entrypoints/docker-entrypoint.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+set -euo pipefail
+
+if [ $# -eq 0 ]; then
+  set -- api
+fi
+
+command="$1"
+shift || true
+
+case "$command" in
+  api)
+    exec /app/entrypoints/api.sh "$@"
+    ;;
+  celery)
+    exec /app/entrypoints/celery.sh "$@"
+    ;;
+  *)
+    exec "$command" "$@"
+    ;;
+esac
diff --git a/manifests/postgres-init.yaml b/manifests/postgres-init.yaml
@@ -0,0 +1,32 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: postgres-page-views-table
+spec:
+  template:
+    spec:
+      restartPolicy: OnFailure
+      containers:
+        - name: create-table
+          image: postgres:16
+          env:
+            - name: PGPASSWORD
+              value: tagup
+          command:
+            - /bin/sh
+            - -c
+            - |
+              set -euo pipefail
+              for i in $(seq 1 60); do
+                if pg_isready --host=postgres --username=tagup --dbname=postgres; then
+                  break
+                fi
+                echo "Waiting for Postgres..."
+                sleep 2
+              done
+              pg_isready --host=postgres --username=tagup --dbname=postgres
+              psql \
+                --host=postgres \
+                --username=tagup \
+                --dbname=postgres \
+                --command="CREATE TABLE IF NOT EXISTS page_views (id BIGSERIAL PRIMARY KEY, time TIMESTAMPTZ NOT NULL, count INTEGER NOT NULL);"
diff --git a/manifests/postgres.yaml b/manifests/postgres.yaml
@@ -0,0 +1,35 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: postgres
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: postgres
+  template:
+    metadata:
+      labels:
+        app: postgres
+    spec:
+      containers:
+        - name: postgres
+          image: postgres:16
+          env:
+            - name: POSTGRES_USER
+              value: tagup
+            - name: POSTGRES_PASSWORD
+              value: tagup
+          ports:
+            - containerPort: 5432
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: postgres
+spec:
+  selector:
+    app: postgres
+  ports:
+    - port: 5432
+      targetPort: 5432
diff --git a/manifests/rabbitmq.yaml b/manifests/rabbitmq.yaml
@@ -0,0 +1,40 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: rabbitmq
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: rabbitmq
+  template:
+    metadata:
+      labels:
+        app: rabbitmq
+    spec:
+      containers:
+        - name: rabbitmq
+          image: rabbitmq:3
+          env:
+            - name: RABBITMQ_DEFAULT_USER
+              value: tagup
+            - name: RABBITMQ_DEFAULT_PASS
+              value: tagup
+          ports:
+            - containerPort: 5672
+            - containerPort: 15672
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: rabbitmq
+spec:
+  selector:
+    app: rabbitmq
+  ports:
+    - name: amqp
+      port: 5672
+      targetPort: 5672
+    - name: management
+      port: 15672
+      targetPort: 15672
diff --git a/manifests/redis.yaml b/manifests/redis.yaml
@@ -0,0 +1,30 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: redis
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: redis
+  template:
+    metadata:
+      labels:
+        app: redis
+    spec:
+      containers:
+        - name: redis
+          image: redis:7
+          ports:
+            - containerPort: 6379
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: redis
+spec:
+  selector:
+    app: redis
+  ports:
+    - port: 6379
+      targetPort: 6379
diff --git a/pyproject.toml b/pyproject.toml
@@ -0,0 +1,21 @@
+[project]
+name = "interview"
+version = "0.1.0"
+description = "FastAPI app with Celery, Redis, and PostgreSQL"
+readme = "README.md"
+requires-python = ">=3.12"
+dependencies = [
+    "celery",
+    "fastapi",
+    "psycopg[binary]",
+    "redis",
+    "sqlalchemy",
+    "uvicorn[standard]",
+]
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.targets.wheel]
+packages = ["src/interview"]
diff --git a/src/interview/__init__.py b/src/interview/__init__.py
diff --git a/src/interview/api.py b/src/interview/api.py
@@ -0,0 +1,19 @@
+import os
+from fastapi import FastAPI
+
+from interview.tasks import increment, aggregate_page_views
+
+app = FastAPI(root_path="/api/v1")
+
+aggregate_queue = os.environ.get("AGGREGATE_QUEUE", "default")
+increment_queue = os.environ.get("INCREMENT_QUEUE", "default")
+
+@app.post("/increment")
+async def increment_api() -> str:
+    increment.apply_async(queue=increment_queue)
+    return "ok"
+
+@app.post("/aggregate")
+async def aggregate_api() -> str:
+    aggregate_page_views.apply_async(queue=aggregate_queue)
+    return "ok"
diff --git a/src/interview/tasks.py b/src/interview/tasks.py
@@ -0,0 +1,46 @@
+import os
+from datetime import datetime, timezone
+
+import redis
+from sqlalchemy import create_engine, text
+
+from interview.worker import celery_app
+
+redis_client = redis.Redis.from_url(os.environ["REDIS_URI"], decode_responses=True)
+engine = create_engine(os.environ["DATABASE_URI"])
+
+
+@celery_app.task
+def increment():
+    redis_client.incrby("page_views", 1)
+
+
+@celery_app.task
+def aggregate_page_views():
+    lock = redis_client.lock("lock:page_views", timeout=30, blocking_timeout=5)
+
+    if not lock.acquire(blocking=True):
+        raise RuntimeError("Could not acquire Redis lock")
+
+    try:
+        count = int(redis_client.get("page_views") or 0)
+        if count == 0:
+            return
+
+        with engine.begin() as connection:
+            connection.execute(
+                text(
+                    """
+                    INSERT INTO page_views (time, count)
+                    VALUES (:time, :count)
+                    """
+                ),
+                {
+                    "time": datetime.now(timezone.utc),
+                    "count": count,
+                },
+            )
+
+        redis_client.delete("page_views")
+    finally:
+        lock.release()
diff --git a/src/interview/worker.py b/src/interview/worker.py
@@ -0,0 +1,40 @@
+from celery import Celery
+from kombu import Exchange, Queue
+
+
+def create_celery_app() -> Celery:
+    modules = ["interview.tasks"]
+
+    app = Celery(
+        "interview",
+        include=modules,
+    )
+
+    default_exchange = Exchange("default", type="direct", durable=True)
+
+    default_queue = Queue(
+        "default",
+        exchange=default_exchange,
+        routing_key="default",
+        durable=True,
+    )
+
+    app.conf.update(
+        task_default_queue="default",
+        task_default_exchange="default",
+        task_default_routing_key="default",
+        task_queues=[default_queue],
+        task_track_started=True,
+        task_acks_late=True,
+        task_reject_on_worker_lost=True,
+        worker_prefetch_multiplier=1,
+        result_expires=3600,
+        worker_hijack_root_logger=False,
+        worker_redirect_stdouts=False,
+        worker_log_color=False,
+    )
+
+    return app
+
+
+celery_app: Celery = create_celery_app()
diff --git a/uv.lock b/uv.lock
