Load Balancer Services

from libcloud.loadbalancer.types import Provider

class Provider:
    """Enumeration of supported load balancer providers"""
    ELB = 'elb'                    # AWS Elastic Load Balancer
    ALB = 'alb'                    # AWS Application Load Balancer  
    GCE = 'gce'                    # Google Cloud Load Balancer
    RACKSPACE = 'rackspace'        # Rackspace Cloud Load Balancers
    NINEFOLD = 'ninefold'          # Ninefold Load Balancer
    BRIGHTBOX = 'brightbox'        # Brightbox Load Balancer
    CLOUDSTACK = 'cloudstack'      # CloudStack Load Balancer
    DIMENSIONDATA = 'dimensiondata' # Dimension Data Load Balancer
    # ... more providers

from libcloud.loadbalancer.providers import get_driver

def get_driver(provider: Provider) -> type[Driver]

from libcloud.loadbalancer.types import Provider
from libcloud.loadbalancer.providers import get_driver

# Get AWS ELB driver class
cls = get_driver(Provider.ELB)

# Initialize driver with credentials
driver = cls('access_key', 'secret_key', region='us-east-1')

class Driver(BaseDriver):
    """Base class for all load balancer drivers"""
    
    def list_protocols(self) -> List[str]
    def list_balancers(self) -> List[LoadBalancer]
    def create_balancer(self, name: str, port: int, protocol: str, algorithm: Algorithm, members: List[Member]) -> LoadBalancer
    def destroy_balancer(self, balancer: LoadBalancer) -> bool
    def get_balancer(self, balancer_id: str) -> LoadBalancer
    def update_balancer(self, balancer: LoadBalancer, **kwargs) -> LoadBalancer
    def balancer_list_members(self, balancer: LoadBalancer) -> List[Member]
    def balancer_attach_member(self, balancer: LoadBalancer, member: Member) -> bool
    def balancer_detach_member(self, balancer: LoadBalancer, member: Member) -> bool
    def balancer_attach_compute_node(self, balancer: LoadBalancer, node: Node) -> Member
    def balancer_detach_compute_node(self, balancer: LoadBalancer, node: Node) -> bool
    def ex_list_balancer_health_checks(self, balancer: LoadBalancer) -> List[Dict]
    def ex_create_balancer_health_check(self, balancer: LoadBalancer, **kwargs) -> Dict

class LoadBalancer:
    """Represents a load balancer"""
    
    id: str
    name: str
    state: State
    ip: str
    port: int
    driver: Driver
    extra: Dict[str, Any]
    
    def attach_member(self, member: Member) -> bool
    def detach_member(self, member: Member) -> bool  
    def list_members(self) -> List[Member]
    def destroy(self) -> bool

class Member:
    """Represents a load balancer member/target"""
    
    id: str
    ip: str
    port: int
    balancer: LoadBalancer
    extra: Dict[str, Any]

class Algorithm:
    """Load balancing algorithms"""
    ROUND_ROBIN = 'round_robin'
    LEAST_CONNECTIONS = 'least_connections'
    RANDOM = 'random'
    WEIGHTED_ROUND_ROBIN = 'weighted_round_robin'
    WEIGHTED_LEAST_CONNECTIONS = 'weighted_least_connections'
    SOURCE_IP = 'source_ip'

class State:
    """Load balancer states"""
    RUNNING = 0
    PENDING = 1
    UNKNOWN = 2
    DELETED = 3

class MemberCondition:
    """Member health conditions"""
    ENABLED = 'enabled'
    DISABLED = 'disabled'
    DRAINING = 'draining'

DEFAULT_ALGORITHM: Algorithm = Algorithm.ROUND_ROBIN

from libcloud.loadbalancer.types import Provider, Algorithm
from libcloud.loadbalancer.providers import get_driver

# Initialize driver
cls = get_driver(Provider.ELB)
driver = cls('access_key', 'secret_key', region='us-east-1')

# List existing load balancers
balancers = driver.list_balancers()
for balancer in balancers:
    print(f"Load Balancer: {balancer.name} ({balancer.state}) - {balancer.ip}:{balancer.port}")

# Check supported protocols
protocols = driver.list_protocols()
print(f"Supported protocols: {protocols}")

# Create members for the load balancer
members = [
    Member(id=None, ip='10.0.1.10', port=80, balancer=None),
    Member(id=None, ip='10.0.1.11', port=80, balancer=None),
    Member(id=None, ip='10.0.1.12', port=80, balancer=None)
]

# Create a new load balancer
balancer = driver.create_balancer(
    name='web-lb',
    port=80,
    protocol='http',
    algorithm=Algorithm.ROUND_ROBIN,
    members=members
)
print(f"Created load balancer: {balancer.name} ({balancer.id})")
print(f"Load balancer IP: {balancer.ip}")

# Get an existing load balancer
balancer = driver.get_balancer('lb-12345')

# List current members
current_members = balancer.list_members()
print(f"Current members: {len(current_members)}")

for member in current_members:
    print(f"  Member: {member.ip}:{member.port} (ID: {member.id})")
    if 'condition' in member.extra:
        print(f"    Status: {member.extra['condition']}")

# Add a new member
new_member = Member(id=None, ip='10.0.1.13', port=80, balancer=balancer)
success = balancer.attach_member(new_member)
print(f"Added new member: {success}")

# Alternative: Add using driver method
success = driver.balancer_attach_member(balancer, new_member)
print(f"Added member via driver: {success}")

# Remove a member
if current_members:
    member_to_remove = current_members[0]
    success = balancer.detach_member(member_to_remove)
    print(f"Removed member {member_to_remove.ip}: {success}")

from libcloud.compute.types import Provider as ComputeProvider
from libcloud.compute.providers import get_driver as get_compute_driver

# Initialize compute driver
compute_cls = get_compute_driver(ComputeProvider.EC2)
compute_driver = compute_cls('access_key', 'secret_key', region='us-east-1')

# Get existing compute nodes
nodes = compute_driver.list_nodes()
web_servers = [node for node in nodes if 'web' in node.name.lower()]

print(f"Found {len(web_servers)} web server nodes")

# Attach compute nodes to load balancer
for node in web_servers[:3]:  # Attach first 3 web servers
    if node.private_ips:  # Use private IP for internal load balancing
        member = driver.balancer_attach_compute_node(balancer, node)
        print(f"Attached node {node.name} ({node.private_ips[0]}) as member {member.id}")

# Alternative: Detach a compute node
if web_servers:
    node_to_detach = web_servers[0]
    success = driver.balancer_detach_compute_node(balancer, node_to_detach)
    print(f"Detached node {node_to_detach.name}: {success}")

# Create load balancer with advanced configuration
advanced_members = [
    Member(id=None, ip='10.0.1.10', port=80, balancer=None),
    Member(id=None, ip='10.0.1.11', port=80, balancer=None)
]

# AWS ELB specific configuration
elb_balancer = driver.create_balancer(
    name='advanced-web-lb',
    port=443,  # HTTPS
    protocol='https',
    algorithm=Algorithm.LEAST_CONNECTIONS,
    members=advanced_members
)

print(f"Created HTTPS load balancer: {elb_balancer.name}")

# Configure health checks (provider specific)
try:
    health_checks = driver.ex_list_balancer_health_checks(elb_balancer)
    print(f"Current health checks: {len(health_checks)}")
    
    # Create custom health check
    health_check = driver.ex_create_balancer_health_check(
        balancer=elb_balancer,
        target='HTTP:80/health',
        interval=30,
        timeout=5,
        healthy_threshold=2,
        unhealthy_threshold=5
    )
    print(f"Created health check: {health_check}")
    
except AttributeError:
    print("Health check configuration not available for this provider")

# Create load balancer for multiple protocols (if supported)
def create_multi_protocol_lb(driver, name, members):
    """Create load balancers for different protocols"""
    protocols = ['http', 'https', 'tcp']
    balancers = {}
    
    for protocol in protocols:
        port = 80 if protocol == 'http' else (443 if protocol == 'https' else 8080)
        
        try:
            balancer = driver.create_balancer(
                name=f'{name}-{protocol}',
                port=port,
                protocol=protocol,
                algorithm=Algorithm.ROUND_ROBIN,
                members=members
            )
            balancers[protocol] = balancer
            print(f"Created {protocol.upper()} load balancer: {balancer.ip}:{balancer.port}")
            
        except Exception as e:
            print(f"Failed to create {protocol} load balancer: {e}")
    
    return balancers

# Usage
multi_members = [
    Member(id=None, ip='10.0.1.10', port=80, balancer=None),
    Member(id=None, ip='10.0.1.11', port=80, balancer=None)
]

protocol_balancers = create_multi_protocol_lb(driver, 'api-lb', multi_members)

import time
from typing import Dict, List

def monitor_load_balancer_health(driver, balancer, interval: int = 60):
    """Monitor load balancer and member health"""
    print(f"Monitoring load balancer: {balancer.name}")
    
    while True:
        try:
            # Refresh balancer state
            current_balancer = driver.get_balancer(balancer.id)
            print(f"Load balancer state: {current_balancer.state}")
            
            # Check member health
            members = driver.balancer_list_members(current_balancer)
            healthy_members = 0
            
            for member in members:
                status = member.extra.get('condition', 'unknown')
                health = member.extra.get('health_status', 'unknown')
                
                print(f"  Member {member.ip}:{member.port} - Status: {status}, Health: {health}")
                
                if status == 'enabled' and health == 'healthy':
                    healthy_members += 1
            
            print(f"Healthy members: {healthy_members}/{len(members)}")
            
            # Alert if too few healthy members
            if healthy_members < 2:
                print("WARNING: Less than 2 healthy members!")
                # Here you could send alerts, create new instances, etc.
            
        except Exception as e:
            print(f"Error monitoring load balancer: {e}")
        
        time.sleep(interval)

def manage_member_weights(driver, balancer, member_weights: Dict[str, int]):
    """Update member weights for weighted load balancing"""
    members = driver.balancer_list_members(balancer)
    
    for member in members:
        member_key = f"{member.ip}:{member.port}"
        if member_key in member_weights:
            weight = member_weights[member_key]
            
            # This is provider-specific - check your provider's documentation
            try:
                # Update member with new weight (example for providers that support it)
                updated_member = driver.ex_update_balancer_member(
                    balancer, member, weight=weight
                )
                print(f"Updated weight for {member_key} to {weight}")
            except AttributeError:
                print(f"Weight management not supported by this provider")

# Usage examples
balancer = driver.get_balancer('lb-12345')

# Set different weights for members
weights = {
    '10.0.1.10:80': 100,  # Full weight
    '10.0.1.11:80': 75,   # Reduced weight  
    '10.0.1.12:80': 50    # Half weight
}

manage_member_weights(driver, balancer, weights)

# Start monitoring (run in separate thread/process)
# monitor_load_balancer_health(driver, balancer, interval=30)

def auto_scale_load_balancer(compute_driver, lb_driver, balancer, template_node, min_members=2, max_members=10):
    """Auto-scale load balancer members based on health"""
    
    members = lb_driver.balancer_list_members(balancer)
    healthy_members = sum(1 for m in members if m.extra.get('health_status') == 'healthy')
    
    print(f"Current members: {len(members)}, Healthy: {healthy_members}")
    
    # Scale up if too few healthy members
    if healthy_members < min_members and len(members) < max_members:
        print("Scaling up: Creating new compute node...")
        
        # Create new compute node based on template
        new_node = compute_driver.create_node(
            name=f"auto-web-{int(time.time())}",
            size=template_node.size,
            image=template_node.image,
            location=template_node.extra.get('availability_zone')
        )
        
        # Wait for node to be running
        compute_driver.wait_until_running([new_node])
        
        # Add to load balancer
        new_member = lb_driver.balancer_attach_compute_node(balancer, new_node)
        print(f"Added new member: {new_member.ip}:{new_member.port}")
    
    # Scale down if too many healthy members
    elif healthy_members > max_members:
        print("Scaling down: Removing excess members...")
        
        # Find oldest member to remove
        members_by_age = sorted(members, key=lambda m: m.extra.get('created_time', ''))
        member_to_remove = members_by_age[0]
        
        # Remove from load balancer
        success = lb_driver.balancer_detach_member(balancer, member_to_remove)
        if success:
            print(f"Removed member: {member_to_remove.ip}:{member_to_remove.port}")
            
            # Optionally terminate the compute node
            # node_to_terminate = compute_driver.get_node(member_to_remove.extra.get('node_id'))
            # compute_driver.destroy_node(node_to_terminate)

# Usage
template_node = compute_driver.list_nodes()[0]  # Use existing node as template
auto_scale_load_balancer(compute_driver, driver, balancer, template_node)

from libcloud.loadbalancer.types import Provider
from libcloud.loadbalancer.providers import get_driver

# Configure multiple load balancer providers
lb_providers = {
    'aws_elb': {
        'driver': get_driver(Provider.ELB),
        'credentials': ('aws_access_key', 'aws_secret_key'),
        'region': 'us-east-1'
    },
    'gce_lb': {
        'driver': get_driver(Provider.GCE),
        'credentials': ('service_account_email', 'key_file_path'),
        'project': 'my-project'
    }
}

# Initialize drivers
lb_drivers = {}
for name, config in lb_providers.items():
    cls = config['driver']
    if 'region' in config:
        lb_drivers[name] = cls(*config['credentials'], region=config['region'])
    elif 'project' in config:
        lb_drivers[name] = cls(*config['credentials'], project=config['project'])

# Create similar load balancers across providers for redundancy
def create_redundant_load_balancers(providers_config, name, members):
    """Create load balancers across multiple providers for redundancy"""
    balancers = {}
    
    for provider_name, driver in lb_drivers.items():
        try:
            balancer = driver.create_balancer(
                name=f'{name}-{provider_name}',
                port=80,
                protocol='http',
                algorithm=Algorithm.ROUND_ROBIN,
                members=members
            )
            balancers[provider_name] = balancer
            print(f"Created load balancer on {provider_name}: {balancer.ip}")
            
        except Exception as e:
            print(f"Failed to create load balancer on {provider_name}: {e}")
    
    return balancers

# Create members for each provider (adjust IPs as needed)
aws_members = [
    Member(id=None, ip='10.0.1.10', port=80, balancer=None),
    Member(id=None, ip='10.0.1.11', port=80, balancer=None)
]

gce_members = [
    Member(id=None, ip='10.1.1.10', port=80, balancer=None),
    Member(id=None, ip='10.1.1.11', port=80, balancer=None)
]

# Create redundant load balancers
redundant_lbs = create_redundant_load_balancers(lb_providers, 'global-api', aws_members)

import json
from datetime import datetime

def backup_load_balancer_config(driver, balancer) -> Dict:
    """Create a backup of load balancer configuration"""
    
    members = driver.balancer_list_members(balancer)
    
    backup_data = {
        'balancer': {
            'name': balancer.name,
            'port': balancer.port,
            'state': balancer.state,
            'extra': balancer.extra
        },
        'members': [
            {
                'ip': member.ip,
                'port': member.port,
                'extra': member.extra
            }
            for member in members
        ],
        'backup_timestamp': datetime.now().isoformat()
    }
    
    # Try to get health checks if supported
    try:
        health_checks = driver.ex_list_balancer_health_checks(balancer)
        backup_data['health_checks'] = health_checks
    except AttributeError:
        pass
    
    print(f"Backed up load balancer {balancer.name} with {len(members)} members")
    return backup_data

def restore_load_balancer_config(driver, backup_data, new_name=None):
    """Restore load balancer from backup"""
    
    balancer_config = backup_data['balancer']
    name = new_name or balancer_config['name']
    
    # Recreate members
    members = [
        Member(id=None, ip=m['ip'], port=m['port'], balancer=None)
        for m in backup_data['members']
    ]
    
    # Create load balancer
    try:
        restored_balancer = driver.create_balancer(
            name=name,
            port=balancer_config['port'],
            protocol=balancer_config['extra'].get('protocol', 'http'),
            algorithm=Algorithm.ROUND_ROBIN,
            members=members
        )
        
        print(f"Restored load balancer: {restored_balancer.name}")
        
        # Restore health checks if they were backed up
        if 'health_checks' in backup_data:
            for hc in backup_data['health_checks']:
                try:
                    driver.ex_create_balancer_health_check(restored_balancer, **hc)
                except (AttributeError, Exception) as e:
                    print(f"Could not restore health check: {e}")
        
        return restored_balancer
        
    except Exception as e:
        print(f"Failed to restore load balancer: {e}")
        return None

# Usage
balancer = driver.get_balancer('lb-12345')

# Create backup
backup = backup_load_balancer_config(driver, balancer)

# Save to file
with open(f'lb_backup_{balancer.name}_{datetime.now().strftime("%Y%m%d_%H%M%S")}.json', 'w') as f:
    json.dump(backup, f, indent=2)

# Restore from backup
restored_lb = restore_load_balancer_config(driver, backup, 'restored-lb')

from libcloud.loadbalancer.types import LoadBalancerError
from libcloud.common.types import LibcloudError, InvalidCredsError

try:
    # Create load balancer
    balancer = driver.create_balancer(
        name='test-lb',
        port=80,
        protocol='http',
        algorithm=Algorithm.ROUND_ROBIN,
        members=members
    )
except InvalidCredsError:
    print("Invalid credentials for load balancer provider")
except LoadBalancerError as e:
    print(f"Load balancer specific error: {e}")
except LibcloudError as e:
    print(f"General Libcloud error: {e}")

# Check balancer state before operations
if balancer.state == State.RUNNING:
    success = driver.destroy_balancer(balancer)
elif balancer.state == State.PENDING:
    print("Load balancer is still being created")

# AWS ELB specific features
elb_driver = get_driver(Provider.ELB)('access_key', 'secret_key')

# Create ELB with AWS-specific configuration
elb_balancer = elb_driver.create_balancer(
    name='aws-elb',
    port=80,
    protocol='http',
    algorithm=Algorithm.ROUND_ROBIN,
    members=members,
    ex_scheme='internet-facing',      # Internet-facing vs internal
    ex_security_groups=['sg-12345'],  # Security groups
    ex_subnets=['subnet-12345'],      # VPC subnets
    ex_cross_zone=True               # Cross-zone load balancing
)

# Google Cloud Load Balancer specific features
gce_driver = get_driver(Provider.GCE)('email', 'key_file', project='my-project')

# Create GCE load balancer with specific configuration
gce_balancer = gce_driver.create_balancer(
    name='gce-lb',
    port=80,
    protocol='http',
    algorithm=Algorithm.ROUND_ROBIN,
    members=members,
    ex_region='us-central1',          # Regional load balancer
    ex_session_affinity='CLIENT_IP'   # Session affinity
)