Task Actions

Task actions in Droe provide a specialized way to define and execute discrete units of work or automation tasks. They're designed for workflow automation, process management, and building executable task sequences.

Tasks vs Actions

Droe has two different constructs for executable code:

Feature	Tasks	Actions
Parameters	✅ Support parameters (NEW!)	✅ Support parameters
Return Values	❌ No return values (void procedures)	✅ Return typed values
Syntax	`task name with params` ... `end task`	`action name with params gives type` ... `end action`
Execution	`run task_name with args`	`run module.action with params`
Use Case	Automation workflows, parameterized void procedures	Reusable functions, data processing
Module Scope	Standalone or in modules	Must be in modules

When to use Tasks:

Automation workflows and processes
System maintenance operations
Sequential execution of steps
No need for return values

When to use Actions:

Reusable functions with parameters
Data transformation and calculations
Functions that return computed values
Cross-module code sharing

Basic Task Syntax

Simple Task Declaration

task task_name
  // Task implementation
end task

Note: Tasks support both end and end task for closing the block.

Task with Parameters (NEW!)

Tasks now support parameters, making them more flexible and reusable:

task greet_person with name which is text
  display "Hello, " + name + "!"
  display "Welcome to the Droelang community!"
end task

// Execute the task with arguments
run greet_person with "Alice"

Task with Multiple Parameters

task process_order with order_id which is int, customer_name which is text, amount which is decimal
  display "Processing order #" + order_id
  display "Customer: " + customer_name
  display "Amount: $" + amount
  display "Order processed successfully!"
end task

// Execute with multiple arguments
run process_order with 12345, "John Doe", 99.99

Task with Implementation

task send_notification
  display "Sending notification..."
  display "Notification sent successfully!"
end task

// Execute the task
run send_notification

Task Examples from Droe

Based on the Droe examples, here are working task patterns:

Basic Task Actions

task send_reminder
  display "Don't forget to log in"
end task

task greet_user
  display "Hello! Welcome to Droe"
  display "Hope you enjoy using task actions!"
end task

task process_data
  set count to 5
  display "Processing data..."
  display count
  display "Processing complete!"
end task

display "Running send_reminder task:"
run send_reminder

display ""
display "Running greet_user task:"
run greet_user

display ""
display "Running process_data task:"
run process_data

display ""
display "Task actions demonstration complete!"

Practical Task Applications

System Maintenance Tasks

task cleanup_temp_files
  display "🧹 Starting cleanup of temporary files..."
  display "Scanning temp directory..."
  display "Found 15 temporary files"
  display "Removing old files..."
  display "Cleanup completed successfully!"
end task

task backup_database
  display "💾 Starting database backup..."
  set timestamp which is text to "2024-01-15-10-30"
  display "Creating backup: backup_[timestamp].sql"
  display "Backup completed successfully!"
end task

task check_system_health
  display "🔍 Checking system health..."
  display "✅ CPU usage: Normal"
  display "✅ Memory usage: Normal"
  display "✅ Disk space: Available"
  display "✅ Network: Connected"
  display "System health check completed!"
end task

display "=== System Maintenance Tasks ==="
run cleanup_temp_files
display ""
run backup_database
display ""
run check_system_health

Data Processing Workflows

task validate_input_data
  display "📋 Validating input data..."
  set validation_errors which is int to 0
  display "Checking data format..."
  display "Checking required fields..."
  display "Validation completed: [validation_errors] errors found"
end task

task transform_data
  display "🔄 Transforming data..."
  display "Converting formats..."
  display "Applying business rules..."
  display "Data transformation completed!"
end task

task generate_report
  display "📊 Generating report..."
  set report_name which is text to "monthly_summary_2024_01.pdf"
  display "Processing data..."
  display "Creating visualizations..."
  display "Report generated: [report_name]"
end task

task send_report_notification
  display "📧 Sending report notification..."
  display "Notifying stakeholders..."
  display "Email notifications sent!"
end task

// Execute data processing workflow
display "=== Data Processing Workflow ==="
run validate_input_data
display ""
run transform_data
display ""
run generate_report
display ""
run send_report_notification

User Management Tasks

task create_user_account
  display "👤 Creating new user account..."
  set new_user_id which is int to 12345
  display "Generating user ID: [new_user_id]"
  display "Setting up user profile..."
  display "Sending welcome email..."
  display "User account created successfully!"
end task

task deactivate_inactive_users
  display "🔒 Deactivating inactive users..."
  set inactive_users which are list of int to [1001, 1002, 1003]
  set deactivated_count which is int to 0

  for each user_id in inactive_users
    set deactivated_count to deactivated_count + 1
    display "Deactivating user ID: [user_id]"
  end for

  display "Deactivated [deactivated_count] inactive users"
end task

task generate_user_report
  display "📈 Generating user activity report..."
  display "Analyzing user data..."
  display "Creating summary statistics..."
  display "User report generated successfully!"
end task

display "=== User Management Tasks ==="
run create_user_account
display ""
run deactivate_inactive_users
display ""
run generate_user_report

Task Coordination and Sequencing

Sequential Task Execution

task initialize_system
  display "🚀 Initializing system..."
  display "Loading configuration..."
  display "Connecting to database..."
  display "System initialized!"
end task

task load_data
  display "📥 Loading data..."
  display "Reading from data sources..."
  display "Data loaded successfully!"
end task

task start_services
  display "⚙️  Starting services..."
  display "Starting web server..."
  display "Starting background workers..."
  display "All services started!"
end task

task verify_deployment
  display "✅ Verifying deployment..."
  display "Running health checks..."
  display "Testing endpoints..."
  display "Deployment verified!"
end task

// Deployment sequence
display "=== Application Deployment Sequence ==="
run initialize_system
display ""
run load_data
display ""
run start_services
display ""
run verify_deployment
display ""
display "🎉 Deployment completed successfully!"

Conditional Task Execution

task check_prerequisites
  display "🔍 Checking prerequisites..."
  set dependencies_met which is flag to true
  set config_valid which is flag to true

  when dependencies_met and config_valid then
    display "✅ All prerequisites met"
  otherwise
    display "❌ Prerequisites not satisfied"
  end when
end task

task execute_main_process
  display "🏃 Executing main process..."
  display "Processing started..."
  display "Main process completed!"
end task

task cleanup_resources
  display "🧹 Cleaning up resources..."
  display "Releasing locks..."
  display "Closing connections..."
  display "Cleanup completed!"
end task

// Conditional execution workflow
display "=== Conditional Task Workflow ==="
run check_prerequisites

// In a real implementation, you'd check the result of prerequisites
set can_proceed which is flag to true

when can_proceed then
  display ""
  run execute_main_process
otherwise
  display "❌ Cannot proceed - prerequisites not met"
end when

display ""
run cleanup_resources

Monitoring and Logging Tasks

System Monitoring

task monitor_cpu_usage
  display "📊 Monitoring CPU usage..."
  set cpu_usage which is decimal to 45.5

  when cpu_usage is greater than 80 then
    display "⚠️  High CPU usage detected: [cpu_usage]%"
  otherwise
    display "✅ CPU usage normal: [cpu_usage]%"
  end when
end task

task monitor_memory_usage
  display "💾 Monitoring memory usage..."
  set memory_usage which is decimal to 62.3

  when memory_usage is greater than 85 then
    display "⚠️  High memory usage detected: [memory_usage]%"
  otherwise
    display "✅ Memory usage normal: [memory_usage]%"
  end when
end task

task check_disk_space
  display "💿 Checking disk space..."
  set disk_usage which is decimal to 78.9

  when disk_usage is greater than 90 then
    display "🚨 Critical: Disk space low: [disk_usage]%"
  end when

  when disk_usage is greater than 80 and disk_usage is less than or equal to 90 then
    display "⚠️  Warning: Disk space getting low: [disk_usage]%"
  otherwise
    display "✅ Disk space sufficient: [disk_usage]%"
  end when
end task

task generate_monitoring_report
  display "📋 Generating monitoring report..."
  set timestamp which is text to "2024-01-15 10:30:00"
  display "Report timestamp: [timestamp]"
  display "Monitoring report generated!"
end task

// System monitoring sequence
display "=== System Monitoring Tasks ==="
run monitor_cpu_usage
display ""
run monitor_memory_usage
display ""
run check_disk_space
display ""
run generate_monitoring_report

Log Processing Tasks

task rotate_log_files
  display "🔄 Rotating log files..."
  set current_log_size which is decimal to 1024.5

  when current_log_size is greater than 1000 then
    display "Log file size: [current_log_size]MB - rotation needed"
    display "Creating archive: app.log.2024-01-15"
    display "Starting new log file"
  otherwise
    display "Log file size: [current_log_size]MB - no rotation needed"
  end when
end task

task analyze_error_logs
  display "🔍 Analyzing error logs..."
  set error_count which is int to 15
  set warning_count which is int to 32

  display "Errors found: [error_count]"
  display "Warnings found: [warning_count]"

  when error_count is greater than 10 then
    display "⚠️  High error count detected - investigation needed"
  end when
end task

task archive_old_logs
  display "📦 Archiving old log files..."
  set files_archived which is int to 8
  display "Archived [files_archived] old log files"
  display "Archive completed!"
end task

display "=== Log Processing Tasks ==="
run rotate_log_files
display ""
run analyze_error_logs
display ""
run archive_old_logs

Batch Processing Tasks

Data Import/Export

task import_customer_data
  display "📥 Importing customer data..."
  set import_file which is text to "customers_2024_01.csv"
  set records_processed which is int to 0

  display "Reading file: [import_file]"

  // Simulate processing records
  set customer_records which are list of int to [1, 2, 3, 4, 5]
  for each record in customer_records
    set records_processed to records_processed + 1
    display "Processing customer record [record]: [records_processed]/5"
  end for

  display "Import completed: [records_processed] records processed"
end task

task export_sales_data
  display "📤 Exporting sales data..."
  set export_file which is text to "sales_export_2024_01.xlsx"
  set sales_records which is int to 1247

  display "Generating export file: [export_file]"
  display "Exporting [sales_records] sales records..."
  display "Export completed successfully!"
end task

task validate_data_integrity
  display "🔍 Validating data integrity..."
  set validation_checks which are list of text to ["duplicates", "nulls", "formats", "constraints"]
  set checks_passed which is int to 0

  for each check in validation_checks
    set checks_passed to checks_passed + 1
    display "✅ [check] validation passed"
  end for

  display "Data integrity validation completed: [checks_passed]/4 checks passed"
end task

display "=== Data Import/Export Tasks ==="
run import_customer_data
display ""
run export_sales_data
display ""
run validate_data_integrity

Task Best Practices

1. Clear Task Names

// Good: Descriptive task names
task backup_user_database
  display "Backing up user database..."
end task

task send_password_reset_email
  display "Sending password reset email..."
end task

task cleanup_temporary_files
  display "Cleaning up temporary files..."
end task

// Avoid: Generic names
task task1
  display "Doing something..."
end task

2. Informative Output

task process_orders
  display "📦 Processing orders..."
  set start_time which is text to "10:30:00"
  display "Started at: [start_time]"

  set orders_to_process which are list of int to [1001, 1002, 1003]
  set processed_count which is int to 0

  for each order_id in orders_to_process
    set processed_count to processed_count + 1
    display "Processing order #[order_id] ([processed_count]/3)"
  end for

  set end_time which is text to "10:35:00"
  display "Completed at: [end_time]"
  display "✅ Successfully processed [processed_count] orders"
end task

3. Error Handling

task safe_file_operation
  display "📁 Performing file operation..."
  set file_exists which is flag to true
  set file_readable which is flag to true

  when not file_exists then
    display "❌ Error: File not found"
    display "Task aborted"
  otherwise
    when not file_readable then
      display "❌ Error: File not readable"
      display "Task aborted"
    otherwise
      display "✅ File operation completed successfully"
    end when
  end when
end task

4. Progress Reporting

task bulk_data_processing
  display "🔄 Starting bulk data processing..."
  set total_items which is int to 100
  set processed_items which is int to 0
  set batch_size which is int to 10

  // Simulate processing in batches
  set batches which are list of int to [1, 2, 3, 4, 5]

  for each batch in batches
    set processed_items to processed_items + batch_size
    set progress_percent which is decimal to (processed_items * 100) / total_items
    display "Batch [batch] completed - Progress: [progress_percent]% ([processed_items]/[total_items])"
  end for

  display "✅ Bulk processing completed!"
end task

Task Coordination Patterns

Master Task with Subtasks

task prepare_environment
  display "🛠️  Preparing environment..."
  display "Environment ready!"
end task

task execute_tests
  display "🧪 Executing tests..."
  display "All tests passed!"
end task

task generate_results
  display "📊 Generating results..."
  display "Results generated!"
end task

task master_test_workflow
  display "🚀 Starting master test workflow..."

  run prepare_environment
  display ""

  run execute_tests
  display ""

  run generate_results
  display ""

  display "✅ Master workflow completed successfully!"
end task

// Execute the master workflow
run master_test_workflow

Parallel Task Simulation

task concurrent_task_a
  display "🔄 Task A: Starting..."
  display "🔄 Task A: Processing..."
  display "✅ Task A: Completed!"
end task

task concurrent_task_b
  display "🔄 Task B: Starting..."
  display "🔄 Task B: Processing..."
  display "✅ Task B: Completed!"
end task

task coordinate_parallel_tasks
  display "🚀 Coordinating parallel tasks..."
  display "Starting concurrent execution..."

  // In actual parallel execution, these would run simultaneously
  run concurrent_task_a
  run concurrent_task_b

  display "✅ All parallel tasks completed!"
end task

run coordinate_parallel_tasks

Next Steps

Now that you understand task actions in Droe:

CLI Reference - Command-line tools for running tasks
WebAssembly - How tasks compile to WASM
Debugging - Troubleshooting task execution
Modules - Organizing tasks in modules

Task actions provide a powerful way to automate workflows and manage complex processes in Droe. Use them to build reliable, maintainable automation solutions.