gcloud

# Google Cloud CLI

The `gcloud` CLI manages GCP resources, configurations, and deployments from the terminal.

## Setup

```bash
# Install gcloud CLI
curl https://sdk.cloud.google.com | bash
exec -l $SHELL

# Initialize and authenticate
gcloud init
gcloud auth login
gcloud auth application-default login

# Set project and region
gcloud config set project my-project-id
gcloud config set compute/region us-central1
gcloud config set compute/zone us-central1-a

# Named configurations for multiple projects
gcloud config configurations create production
gcloud config configurations activate production
```

## Compute Engine

```bash
# Create a VM instance
gcloud compute instances create web-server \
  --machine-type=e2-medium \
  --image-family=ubuntu-2204-lts \
  --image-project=ubuntu-os-cloud \
  --boot-disk-size=30GB \
  --boot-disk-type=pd-ssd \
  --subnet=my-subnet \
  --tags=http-server,https-server \
  --service-account=app-sa@my-project.iam.gserviceaccount.com

# List instances
gcloud compute instances list \
  --filter="status=RUNNING AND labels.env=production" \
  --format="table(name,zone,machineType.basename(),networkInterfaces[0].accessConfigs[0].natIP)"

# SSH into instance
gcloud compute ssh web-server --zone=us-central1-a

# Stop/start/delete
gcloud compute instances stop web-server --zone=us-central1-a
gcloud compute instances start web-server --zone=us-central1-a
gcloud compute instances delete web-server --zone=us-central1-a

# Firewall rules
gcloud compute firewall-rules create allow-http \
  --network=default --allow=tcp:80,tcp:443 \
  --target-tags=http-server --source-ranges=0.0.0.0/0
```

## Cloud Storage

```bash
# Bucket operations
gcloud storage buckets create gs://my-bucket --location=us-central1
gcloud storage ls gs://my-bucket/
gcloud storage cp file.txt gs://my-bucket/path/
gcloud storage rsync ./local-dir gs://my-bucket/remote/ --delete-unmatched-destination-objects

# Set lifecycle rules
gcloud storage buckets update gs://my-bucket \
  --lifecycle-file=lifecycle.json

# Signed URLs
gcloud storage sign-url gs://my-bucket/file.pdf --duration=1h
```

## Cloud Functions

```bash
# Deploy a Cloud Function (2nd gen)
gcloud functions deploy my-function \
  --gen2 \
  --runtime=python312 \
  --region=us-central1 \
  --source=. \
  --entry-point=handler \
  --trigger-http \
  --allow-unauthenticated \
  --memory=256MB \
  --timeout=60s \
  --set-env-vars="DB_HOST=10.0.0.5,ENV=production"

# Invoke and view logs
gcloud functions call my-function --data='{"key":"value"}'
gcloud functions logs read my-function --region=us-central1 --limit=50

# List functions
gcloud functions list --format="table(name,status,runtime)"
```

## IAM

```bash
# Service accounts
gcloud iam service-accounts create app-sa \
  --display-name="Application Service Account"

gcloud iam service-accounts keys create key.json \
  --iam-account=app-sa@my-project.iam.gserviceaccount.com

# Role bindings
gcloud projects add-iam-policy-binding my-project \
  --member="serviceAccount:app-sa@my-project.iam.gserviceaccount.com" \
  --role="roles/storage.objectViewer"

# View IAM policy
gcloud projects get-iam-policy my-project \
  --format="table(bindings.role,bindings.members)"

# Impersonate service account
gcloud auth print-access-token --impersonate-service-account=app-sa@my-project.iam.gserviceaccount.com
```

## GKE

```bash
# Create GKE cluster
gcloud container clusters create my-cluster \
  --num-nodes=3 \
  --machine-type=e2-standard-4 \
  --region=us-central1 \
  --enable-autoscaling --min-nodes=1 --max-nodes=10

# Get credentials for kubectl
gcloud container clusters get-credentials my-cluster --region=us-central1

# Resize node pool
gcloud container clusters resize my-cluster --num-nodes=5 --region=us-central1
```

## Useful Patterns

```bash
# Format output for scripting
gcloud compute instances list --format="value(name)" | while read name; do
  echo "Processing $name"
done

# Describe any resource as JSON
gcloud compute instances describe web-server --zone=us-central1-a --format=json

# Billing and cost
gcloud billing accounts list
gcloud billing projects describe my-project

# Cloud SQL
gcloud sql instances create my-db --database-version=POSTGRES_15 \
  --tier=db-custom-2-8192 --region=us-central1
gcloud sql connect my-db --user=postgres

# Pub/Sub
gcloud pubsub topics create my-topic
gcloud pubsub subscriptions create my-sub --topic=my-topic
```