prvng_kcl/examples/simple_workflow.k

# Simple Workflow Example
# Demonstrates basic workflow creation with sequential operations

import ..main

# Simple web application deployment workflow
web_app_deployment: main.BatchWorkflow = main.BatchWorkflow {
    workflow_id: "webapp_deploy_001"
    name: "Web Application Deployment"
    description: "Deploy a simple web application with database backend"

    operations: [
        # Step 1: Create database server
        main.BatchOperation {
            operation_id: "create_database"
            name: "Create Database Server"
            operation_type: "server"
            provider: "upcloud"
            action: "create"
            parameters: {
                "hostname": "webapp-db"
                "plan": "1xCPU-2GB"
                "zone": "fi-hel2"
                "server_type": "database"
            }
            priority: 10
            timeout: 600  # 10 minutes
        }

        # Step 2: Create web servers (can run in parallel)
        main.BatchOperation {
            operation_id: "create_web_servers"
            name: "Create Web Servers"
            operation_type: "server"
            provider: "upcloud"
            action: "create"
            parameters: {
                "server_count": "2"
                "hostname_prefix": "webapp-web"
                "plan": "1xCPU-1GB"
                "zone": "fi-hel2"
                "server_type": "web"
            }
            priority: 10
            timeout: 600
            allow_parallel: True
        }

        # Step 3: Install database after database server is ready
        main.BatchOperation {
            operation_id: "install_database"
            name: "Install PostgreSQL"
            operation_type: "taskserv"
            action: "create"
            parameters: {
                "taskserv": "postgresql"
                "version": "15"
                "target_servers": "webapp-db"
            }
            dependencies: [
                main.DependencyDef {
                    target_operation_id: "create_database"
                    dependency_type: "sequential"
                    timeout: 300
                }
            ]
            priority: 8
            timeout: 900  # 15 minutes for database installation
        }

        # Step 4: Install web stack after web servers are ready
        main.BatchOperation {
            operation_id: "install_web_stack"
            name: "Install Web Stack"
            operation_type: "taskserv"
            action: "create"
            parameters: {
                "taskserv": "nginx"
                "target_servers": "webapp-web-*"
                "config_template": "reverse_proxy"
            }
            dependencies: [
                main.DependencyDef {
                    target_operation_id: "create_web_servers"
                    dependency_type: "sequential"
                    timeout: 300
                }
            ]
            priority: 8
            timeout: 600
        }

        # Step 5: Configure application after all components are ready
        main.BatchOperation {
            operation_id: "configure_application"
            name: "Configure Web Application"
            operation_type: "custom"
            action: "configure"
            parameters: {
                "config_type": "application"
                "database_url": "postgres://webapp-db:5432/webapp"
                "web_servers": "webapp-web-01,webapp-web-02"
            }
            dependencies: [
                main.DependencyDef {
                    target_operation_id: "install_database"
                    dependency_type: "sequential"
                    timeout: 60
                },
                main.DependencyDef {
                    target_operation_id: "install_web_stack"
                    dependency_type: "sequential"
                    timeout: 60
                }
            ]
            priority: 5
            timeout: 300
        }
    ]

    # Workflow settings
    max_parallel_operations: 3
    global_timeout: 3600  # 1 hour total
    fail_fast: True  # Stop on first failure

    # Simple filesystem storage for this example
    storage: main.StorageConfig {
        backend: "filesystem"
        base_path: "./webapp_deployments"
        enable_persistence: True
        retention_hours: 168  # 1 week
    }

    # Basic monitoring
    monitoring: main.MonitoringConfig {
        enabled: True
        backend: "prometheus"
        enable_tracing: False  # Simplified for example
        log_level: "info"
    }

    # Conservative retry policy
    default_retry_policy: main.RetryPolicy {
        max_attempts: 2
        initial_delay: 30
        backoff_multiplier: 2
        retry_on_errors: ["timeout", "connection_error"]
    }

    # Enable rollback for safety
    default_rollback_strategy: main.RollbackStrategy {
        enabled: True
        strategy: "immediate"
        preserve_partial_state: False
    }
}