GCP Cloud Run Patterns Cloud Run Service Pattern

Containerized web service on Cloud Run

When to use: ['Web applications and APIs', 'Need any runtime or library', 'Complex services with multiple endpoints', 'Stateless containerized workloads']

```dockerfile

Dockerfile - Multi-stage build for smaller image

FROM node:20-slim AS builder WORKDIR /app COPY package*.json ./ RUN npm ci --only=production

FROM node:20-slim WORKDIR /app

Copy only production dependencies

COPY --from=builder /app/node_modules ./node_modules COPY src ./src COPY package.json ./

Cloud Run uses PORT env variable

ENV PORT=8080 EXPOSE 8080

Run as non-root user

USER node

CMD ["node", "src/index.js"]

// src/index.js const express = require('express'); const app = express();

app.use(express.json());

// Health check endpoint app.get('/health', (req, res) => { res.status(200).send('OK'); });

// API routes app.get('/api/items/:id', async (req, res) => { try { const item = await getItem(req.params.id); res.json(item); } catch (error) { console.error('Error:', error); res.status(500).json({ error: 'Internal server error' }); } });

// Graceful shutdown process.on('SIGTERM', () => { console.log('SIGTERM received, shutting down gracefully'); server.close(() => { console.log('Server closed'); process.exit(0); }); });

const PORT = process.env.PORT || 8080; const server = app.listen(PORT, () => { console.log(Server listening on port ${PORT}); });

cloudbuild.yaml

steps: # Build the container image - name: 'gcr.io/cloud-builders/docker' args: ['build', '-t', 'gcr.io/$PROJECT_ID/my-service:$COMMIT_SHA', '.']

# Push the container image - name: 'gcr.io/cloud-builders/docker' args: ['push', 'gcr.io/$PROJECT_ID/my-service:$COMMIT_SHA']

# Deploy to Cloud Run - name: 'gcr.io/google.com/cloudsdktool/cloud-sdk' entrypoint: gcloud args: - 'run' - 'deploy' - 'my-service' - '--image=gcr.io/$PROJECT_ID/my-service:$COMMIT_SHA' - '--region=us-central1' - '--platform=managed' - '--allow-unauthenticated' - '--memory=512Mi' - '--cpu=1' - '--min-instances=1' - '--max-instances=100'

Cloud Run Functions Pattern

Event-driven functions (formerly Cloud Functions)

When to use: ['Simple event handlers', 'Pub/Sub message processing', 'Cloud Storage triggers', 'HTTP webhooks']

```javascript // HTTP Function // index.js const functions = require('@google-cloud/functions-framework');

functions.http('helloHttp', (req, res) => { const name = req.query.name || req.body.name || 'World'; res.send(Hello, ${name}!); });

// Pub/Sub Function const functions = require('@google-cloud/functions-framework');

functions.cloudEvent('processPubSub', (cloudEvent) => { // Decode Pub/Sub message const message = cloudEvent.data.message; const data = message.data ? JSON.parse(Buffer.from(message.data, 'base64').toString()) : {};

console.log('Received message:', data);

// Process message processMessage(data); });

// Cloud Storage Function const functions = require('@google-cloud/functions-framework');

functions.cloudEvent('processStorageEvent', async (cloudEvent) => { const file = cloudEvent.data;

console.log(Event: ${cloudEvent.type}); console.log(Bucket: ${file.bucket}); console.log(File: ${file.name});

if (cloudEvent.type === 'google.cloud.storage.object.v1.finalized') { await processUploadedFile(file.bucket, file.name); } });

Deploy HTTP function

gcloud functions deploy hello-http \ --gen2 \ --runtime nodejs20 \ --trigger-http \ --allow-unauthenticated \ --region us-central1

Deploy Pub/Sub function

gcloud functions deploy process-messages \ --gen2 \ --runtime nodejs20 \ --trigger-topic my-topic \ --region us-central1

Deploy Cloud Storage function

gcloud functions deploy process-uploads \ --gen2 \ --runtime nodejs20 \ --trigger-event-filters="type=google.cloud.storage.object.v1.finalized" \ --trigger-event-filters="bucket=my-bucket" \ --region us-central1

Cold Start Optimization Pattern

Minimize cold start latency for Cloud Run

When to use: ['Latency-sensitive applications', 'User-facing APIs', 'High-traffic services']

```javascript

1. Enable Startup CPU Boost

```bash gcloud run deploy my-service \ --cpu-boost \ --region us-central1

1. Set Minimum Instances gcloud run deploy my-service \ --min-instances 1 \ --region us-central1

2. Optimize Container Image

Use distroless for minimal image

FROM node:20-slim AS builder WORKDIR /app COPY package*.json ./ RUN npm ci --only=production

FROM gcr.io/distroless/nodejs20-debian12 WORKDIR /app COPY --from=builder /app/node_modules ./node_modules COPY src ./src CMD ["src/index.js"]

1. Lazy Initialize Heavy Dependencies // Lazy load heavy libraries let bigQueryClient = null;

function getBigQueryClient() { if (!bigQueryClient) { const { BigQuery } = require('@google-cloud/bigquery'); bigQueryClient = new BigQuery(); } return bigQueryClient; }

// Only initialize when needed app.get('/api/analytics', async (req, res) => { const client = getBigQueryClient(); const results = await client.query({...}); res.json(results); });

1. Increase Memory (More CPU)

Higher memory = more CPU during startup

gcloud run deploy my-service \ --memory 1Gi \ --cpu 2 \ --region us-central1

Anti-Patterns

❌ CPU-Intensive Work Without Concurrency=1

Why bad: CPU is shared across concurrent requests. CPU-bound work will starve other requests, causing timeouts.

❌ Writing Large Files to /tmp

Why bad: /tmp is an in-memory filesystem. Large files consume your memory allocation and can cause OOM errors.

❌ Long-Running Background Tasks

Why bad: Cloud Run throttles CPU to near-zero when not handling requests. Background tasks will be extremely slow or stall.

⚠️ Sharp Edges