GCP Cloud Basics

Google Cloud Platform (GCP) Fundamentals

Cloud Team

Cloud Architects

May 22, 2026

14 min read

GCP Cloud Functions & API Gateway

Complete Deployment Guide with Terminal Commands

Initial Setup
Enable Services
IAM Roles
Cloud Functions
API Gateway
API Keys
Testing
Update & Versioning
Delete Resources
Troubleshooting

Initial Setup

Authentication & Project Setup Basic

# Authenticate with GCP
gcloud auth login

# List all projects
gcloud projects list

# Set the active project
gcloud config set project PROJECT_ID

# Set environment variables for easier reference
export PROJECT_ID="your-project-id"
export REGION="us-central1"

export REGION="us-central1"

# Verify variables are set
echo "Project ID: $PROJECT_ID"
echo "Region: $REGION"

Enable Required Services

Basic Enable GCP Services

# Enable all required services
gcloud services enable cloudfunctions.googleapis.com \
  run.googleapis.com \
  cloudbuild.googleapis.com \
  artifactregistry.googleapis.com \
  apigateway.googleapis.com \
  servicemanagement.googleapis.com \
  servicecontrol.googleapis.com \
  logging.googleapis.com \
  --project=$PROJECT_ID

Tip: You can check which services are already enabled with:
gcloud services list --enabled --project=$PROJECT_ID

IAM Roles for Developers

Intermediate Required IAM Roles

# List of roles needed for Cloud Functions and API Gateway development:
# roles/apigateway.admin
# roles/cloudfunctions.admin
# roles/cloudfunctions.invoker
# roles/iam.serviceAccountUser
# roles/serviceusage.serviceUsageViewer
# roles/serviceusage.serviceUsageConsumer
# roles/logging.viewer
# roles/monitoring.viewer
# roles/serviceusage.serviceUsageAdmin

# Grant a user the necessary roles
gcloud projects add-iam-policy-binding $PROJECT_ID \
--member="user:user@example.com" \
--role="roles/cloudfunctions.admin"

# Repeat for other required roles

Deploy Cloud Functions

Intermediate Deploy Cloud Functions

# Deploy a public HTTP function (no authentication)
gcloud functions deploy getHelloWorld \
  --gen2 \
  --runtime nodejs20 \
  --trigger-http \
  --region $REGION \
  --allow-unauthenticated \
  --source="./functions/getHelloWorld" \
  --entry-point="getHelloWorld" \
  --project="$PROJECT_ID"

# Deploy a private HTTP function (requires authentication)
gcloud functions deploy getUserData \
  --gen2 \
  --runtime nodejs20 \
  --trigger-http \
  --region $REGION \
  --no-allow-unauthenticated \
  --source="./functions/getUserData" \
  --entry-point="getUserData" \
  --project="$PROJECT_ID"

Note: After deployment, you'll get URLs like:
https://$REGION-$PROJECT_ID.cloudfunctions.net/getHelloWorld
https://$REGION-$PROJECT_ID.cloudfunctions.net/getUserData

Deploy API Gateway

Advanced API Gateway Deployment

# Set environment variables for API Gateway
export PROJECT_ID="your-project-id"
export REGION="us-central1"
export GATEWAY_NAME="user-check-gateway"
export API_NAME="user-check-api"
export API_CONFIG="user-check-config"
export API_YAML="api-gateway.yaml"

# Step 1: Create the API
gcloud api-gateway apis create "$API_NAME" --project="$PROJECT_ID"

# Step 2: Create API config (requires YAML file)
gcloud api-gateway api-configs create "$API_CONFIG" \
  --api="$API_NAME" \
  --openapi-spec="$API_YAML" \
  --project="$PROJECT_ID"

# Step 3: Create the gateway
gcloud api-gateway gateways create "$GATEWAY_NAME" \
  --api="$API_NAME" \
  --api-config="$API_CONFIG" \
  --location="$REGION" \
  --project="$PROJECT_ID"

# Get the Gateway URL
export GATEWAY_URL=$(gcloud api-gateway gateways describe "$GATEWAY_NAME" \
--location="$REGION" --project="$PROJECT_ID" \
--format="value(defaultHostname)")
echo "API Gateway is live at: https://$GATEWAY_URL"

API Keys Management

Intermediate API Keys

# Check if API key already exists
EXISTING_API_KEY_NAME=$(gcloud alpha services api-keys list \
  --filter='displayName="helloWorld API Key"' \
  --format="value(name)" | tail -n 1)

if [ -z "$EXISTING_API_KEY_NAME" ]; then
  echo "Creating new API Key..."
  # Create API Key
  gcloud alpha services api-keys create \
    --display-name="helloWorld API Key" \
    --format="value(name)"
  sleep 10
else
  echo "Reusing existing API Key: $EXISTING_API_KEY_NAME"
fi

# Get the API key value
API_KEY=$(gcloud alpha services api-keys get-key-string "$EXISTING_API_KEY_NAME" \
  --format="get(keyString)" 2>/dev/null)
echo "API Key: $API_KEY"

# Enable the gateway service for API key authentication
# First, get the managed service name
MANAGED_SERVICE=$(gcloud api-gateway apis describe "$API_NAME" \
--project="$PROJECT_ID" --format="value(managedService)")

# Enable the service
gcloud services enable "$MANAGED_SERVICE" --project="$PROJECT_ID"

Testing the Deployment

Basic Test Endpoints

# Test public endpoint (no API key needed)
curl -X GET "https://$GATEWAY_URL/get-hello"

# Test secure endpoint (API key required)
curl -X GET "https://$GATEWAY_URL/get-user-data" \
  -H "x-api-key: $API_KEY"

# Test POST endpoint
curl -X POST "https://$GATEWAY_URL/post-submit-data" \
  -H "Content-Type: application/json" \
  -d '{"name": "John", "email": "john@example.com"}'

Update & Versioning

Advanced Update API Gateway

# Create a new API config version
NEW_API_CONFIG="user-check-gateway-config-v2"

gcloud api-gateway api-configs create "$NEW_API_CONFIG" \
  --api="$API_NAME" \
  --openapi-spec="$API_YAML" \
  --project="$PROJECT_ID"

# Update the gateway to use the new config
gcloud api-gateway gateways update "$GATEWAY_NAME" \
  --api="$API_NAME" \
  --api-config="$NEW_API_CONFIG" \
  --location="$REGION" \
  --project="$PROJECT_ID"

# Rollback to previous version if needed
gcloud api-gateway gateways update "$GATEWAY_NAME" \
  --api-config="previous-config-name" \
  --location="$REGION" \
  --project="$PROJECT_ID"

Delete Resources

Intermediate Cleanup Resources

# Delete Cloud Function
gcloud functions delete FUNCTION_NAME \
--region=$REGION \
--project=$PROJECT_ID

# Delete API Gateway and related resources
gcloud api-gateway gateways delete "$GATEWAY_NAME" \
  --location="$REGION" \
  --project="$PROJECT_ID"

gcloud api-gateway api-configs delete "$API_CONFIG" \
  --api="$API_NAME" \
  --project="$PROJECT_ID"

gcloud api-gateway apis delete "$API_NAME" \
  --project="$PROJECT_ID"

# Delete API Key
gcloud alpha services api-keys delete "API_KEY_NAME"

Troubleshooting

Advanced Common Issues & Solutions

# Check API Gateway status
gcloud api-gateway gateways describe "$GATEWAY_NAME" \
  --location="$REGION" \
  --project="$PROJECT_ID"

# Check API configs
gcloud api-gateway api-configs list \
  --api="$API_NAME" \
  --project="$PROJECT_ID"

# Check Cloud Function logs
gcloud functions logs read FUNCTION_NAME \
  --region=$REGION \
  --project=$PROJECT_ID

Common Issues:

API Gateway returns 404: Check if the managed service is enabled
Authentication errors: Verify API key is correctly configured and restricted
CORS issues: Configure CORS in your Cloud Function code
Permission errors: Verify IAM roles are properly assigned

Pro Tips

Always use the --dry-run flag when available to test commands without making changes
Use environment variables to avoid repetition and mistakes
Enable detailed logging for debugging complex issues
Regularly clean up unused resources to avoid unnecessary costs
Use version control for your API Gateway configuration files

Keep Reading

DevOps

Docker Networking Demystified: Bridge, Host & Overlay

8 min read Read More

Cloud

AWS IAM Roles vs Users vs Policies

10 min read Read More

Programming

Understanding Python's GIL & Multiprocessing

14 min read Read More

Google Cloud Platform (GCP) Fundamentals

GCP Cloud Functions & API Gateway

Table of Contents

Initial Setup

Enable Required Services

IAM Roles for Developers

Deploy Cloud Functions

Deploy API Gateway

API Keys Management

Testing the Deployment

Update & Versioning

Delete Resources

Troubleshooting

Pro Tips

Keep Reading

Docker Networking Demystified: Bridge, Host & Overlay

AWS IAM Roles vs Users vs Policies

Understanding Python's GIL & Multiprocessing

Begin Programming Diagnostic

Compiling Cognitive Telemetry

Your Programming Skill Scan Report