update_lambda.sh

#!/bin/bash

BACKEND_DIR="./backend"
DOCKER_IMAGE_NAME="docker-lambda"
AWS_REGION="us-east-1"
ECR_URL="754754248018.dkr.ecr.$AWS_REGION.amazonaws.com/$DOCKER_IMAGE_NAME"

CHANGED=0

echo "🚀 Checking for changes in Lambda functions..."
echo ""

# Calculate new checksum, ignoring 'tests/' and 'price_prediction/' directories
NEW_CHECKSUM=$(find "$BACKEND_DIR" -type d \( -name "tests" -o -name "price_prediction" -o -name "route_tests" \) -prune -o -type f -name "*.py" -print0 | sort -z | xargs -0 md5sum | md5sum | awk '{print $1}')

CHECKSUM_FILE=".docker_checksum"

if [ ! -f "$CHECKSUM_FILE" ]; then
    touch "$CHECKSUM_FILE"
fi

OLD_CHECKSUM=$(cat "$CHECKSUM_FILE")

if [ "$NEW_CHECKSUM" != "$OLD_CHECKSUM" ]; then
    echo "📦 Changes detected in Lambda functions (excluding tests & price_prediction). Rebuilding Docker image..."
    
    # Build the Docker image
    docker build --platform linux/amd64 -t $DOCKER_IMAGE_NAME .

    # Authenticate with ECR
    aws ecr get-login-password --region $AWS_REGION | docker login --username AWS --password-stdin $ECR_URL

    # Tag and push the image to ECR
    docker tag $DOCKER_IMAGE_NAME:latest $ECR_URL:latest
    docker push $ECR_URL:latest

    # Store new checksum
    echo "$NEW_CHECKSUM" > "$CHECKSUM_FILE"

    CHANGED=1
else
    echo "🐻 No changes detected in Lambda functions, skipping Docker build."
fi

if [ "$CHANGED" -eq 1 ]; then
    echo "Updating variable names in variable.tf..."
    python3 update_variables.py
    echo "🎉 Docker image updated and pushed to ECR!"
else
    echo "🚀 No updates needed for Terraform."
fi

IMAGE_DIGEST=$(aws ecr describe-images --repository-name docker-lambda --region us-east-1 --query 'sort_by(imageDetails,&imagePushedAt)[-1].imageDigest' --output text)

if [ -n "$IMAGE_DIGEST" ]; then
    echo "🔄 Updating Terraform Lambda image URI... in main.tf"
    awk -v region="$AWS_REGION" -v digest="$IMAGE_DIGEST" '
    {
        gsub(/image_uri[[:space:]]*=[[:space:]]*"[^"]*"/, "image_uri = \"754754248018.dkr.ecr." region ".amazonaws.com/docker-lambda@" digest "\"")
        print
    }' main.tf > temp.tf && mv temp.tf main.tf
    echo "✅ Terraform configuration updated with new image: $IMAGE_DIGEST"
    echo "🎉 Ready for deployment! Run terraform init then terraform apply only if you ready gang"
else
    echo "❌ Failed to fetch latest image digest!"
fi