Event-Driven Architecture in TuskLang - Bash Guide

📡 Revolutionary Event-Driven Architecture Configuration

Event-driven architecture in TuskLang transforms your configuration files into intelligent, reactive systems. No more polling or synchronous communication—everything lives in your TuskLang configuration with dynamic event publishing, intelligent event routing, and comprehensive event processing.

> "We don't bow to any king" – TuskLang event-driven architecture breaks free from traditional request-response constraints and brings modern reactive computing to your Bash applications.

🚀 Core Event-Driven Architecture Directives

Basic Event-Driven Architecture Setup

#event-driven: enabled                  # Enable event-driven architecture
#eda-enabled: true                     # Alternative syntax
#eda-publisher: true                   # Enable event publishing
#eda-subscriber: true                  # Enable event subscription
#eda-broker: redis                     # Event broker type
#eda-topics: true                      # Enable topic management

Advanced Event-Driven Architecture Configuration

#eda-streaming: true                   # Enable event streaming
#eda-patterns: true                    # Enable event patterns
#eda-saga: true                        # Enable saga patterns
#eda-cqrs: true                        # Enable CQRS patterns
#eda-monitoring: true                  # Enable event monitoring
#eda-tracing: true                     # Enable event tracing

🔧 Bash Event-Driven Architecture Implementation

Basic Event Manager

#!/bin/bash
Load event-driven architecture configuration
source <(tsk load event-driven.tsk)
Event-driven architecture configuration
EDA_ENABLED="${eda_enabled:-true}"
EDA_PUBLISHER="${eda_publisher:-true}"
EDA_SUBSCRIBER="${eda_subscriber:-true}"
EDA_BROKER="${eda_broker:-redis}"
EDA_TOPICS="${eda_topics:-true}"
Event manager
class EventManager {
    constructor() {
        this.enabled = EDA_ENABLED
        this.publisher = EDA_PUBLISHER
        this.subscriber = EDA_SUBSCRIBER
        this.broker = EDA_BROKER
        this.topics = EDA_TOPICS
        this.events = new Map()
        this.subscribers = new Map()
        this.stats = {
            events_published: 0,
            events_consumed: 0,
            subscribers_registered: 0,
            topics_created: 0
        }
    }
    
    publishEvent(topic, event) {
        if (!this.publisher) return
        
        const eventData = {
            id: this.generateEventId(),
            topic,
            data: event,
            timestamp: Date.now(),
            publisher: 'event-manager'
        }
        
        this.events.set(eventData.id, eventData)
        this.broadcastEvent(topic, eventData)
        
        this.stats.events_published++
    }
    
    subscribeToTopic(topic, callback) {
        if (!this.subscriber) return
        
        if (!this.subscribers.has(topic)) {
            this.subscribers.set(topic, [])
        }
        
        this.subscribers.get(topic).push(callback)
        this.stats.subscribers_registered++
    }
    
    broadcastEvent(topic, event) {
        const topicSubscribers = this.subscribers.get(topic) || []
        
        topicSubscribers.forEach(callback => {
            try {
                callback(event)
                this.stats.events_consumed++
            } catch (error) {
                console.error('Error in event callback:', error)
            }
        })
    }
    
    generateEventId() {
        return Math.random().toString(36).substr(2, 9)
    }
    
    getStats() {
        return { ...this.stats }
    }
}
Initialize event manager
const eventManager = new EventManager()

Dynamic Event Publishing

#!/bin/bash
Dynamic event publishing
publish_event() {
    local topic="$1"
    local event_data="$2"
    local event_id=$(uuidgen)
    local timestamp=$(date -Iseconds)
    
    # Create event
    local event_file="/tmp/event_${event_id}.json"
    cat > "$event_file" << EOF
{
    "id": "$event_id",
    "topic": "$topic",
    "data": "$event_data",
    "timestamp": "$timestamp",
    "publisher": "event-publisher"
}
EOF
    
    # Publish to broker
    publish_to_broker "$topic" "$event_file"
    
    echo "✓ Event published: $topic ($event_id)"
}
publish_to_broker() {
    local topic="$1"
    local event_file="$2"
    local broker_type="${eda_broker:-redis}"
    
    case "$broker_type" in
        "redis")
            publish_to_redis "$topic" "$event_file"
            ;;
        "kafka")
            publish_to_kafka "$topic" "$event_file"
            ;;
        "rabbitmq")
            publish_to_rabbitmq "$topic" "$event_file"
            ;;
        "file")
            publish_to_file "$topic" "$event_file"
            ;;
        *)
            echo "Unknown broker type: $broker_type"
            return 1
            ;;
    esac
}
publish_to_redis() {
    local topic="$1"
    local event_file="$2"
    local redis_host="${eda_redis_host:-localhost}"
    local redis_port="${eda_redis_port:-6379}"
    
    # Publish event to Redis
    local event_data=$(cat "$event_file")
    redis-cli -h "$redis_host" -p "$redis_port" PUBLISH "$topic" "$event_data" >/dev/null 2>&1
    
    echo "✓ Event published to Redis: $topic"
}
publish_to_kafka() {
    local topic="$1"
    local event_file="$2"
    local kafka_host="${eda_kafka_host:-localhost}"
    local kafka_port="${eda_kafka_port:-9092}"
    
    # Publish event to Kafka
    local event_data=$(cat "$event_file")
    echo "$event_data" | kafka-console-producer.sh --broker-list "$kafka_host:$kafka_port" --topic "$topic" >/dev/null 2>&1
    
    echo "✓ Event published to Kafka: $topic"
}
publish_to_rabbitmq() {
    local topic="$1"
    local event_file="$2"
    local rabbitmq_host="${eda_rabbitmq_host:-localhost}"
    local rabbitmq_port="${eda_rabbitmq_port:-5672}"
    
    # Publish event to RabbitMQ
    local event_data=$(cat "$event_file")
    amqp-publish -u "amqp://$rabbitmq_host:$rabbitmq_port" -r "$topic" -p "$event_data" >/dev/null 2>&1
    
    echo "✓ Event published to RabbitMQ: $topic"
}
publish_to_file() {
    local topic="$1"
    local event_file="$2"
    local events_dir="${eda_events_dir:-/var/log/events}"
    
    # Create events directory
    mkdir -p "$events_dir"
    
    # Copy event to topic directory
    local topic_dir="$events_dir/$topic"
    mkdir -p "$topic_dir"
    cp "$event_file" "$topic_dir/"
    
    echo "✓ Event published to file: $topic"
}

Event Subscription and Consumption

#!/bin/bash
Event subscription and consumption
subscribe_to_topic() {
    local topic="$1"
    local callback_script="$2"
    local broker_type="${eda_broker:-redis}"
    
    case "$broker_type" in
        "redis")
            subscribe_to_redis "$topic" "$callback_script"
            ;;
        "kafka")
            subscribe_to_kafka "$topic" "$callback_script"
            ;;
        "rabbitmq")
            subscribe_to_rabbitmq "$topic" "$callback_script"
            ;;
        "file")
            subscribe_to_file "$topic" "$callback_script"
            ;;
        *)
            echo "Unknown broker type: $broker_type"
            return 1
            ;;
    esac
}
subscribe_to_redis() {
    local topic="$1"
    local callback_script="$2"
    local redis_host="${eda_redis_host:-localhost}"
    local redis_port="${eda_redis_port:-6379}"
    
    echo "Subscribing to Redis topic: $topic"
    
    # Subscribe to Redis topic
    redis-cli -h "$redis_host" -p "$redis_port" SUBSCRIBE "$topic" | while read -r line; do
        if [[ "$line" =~ ^message$ ]]; then
            read -r topic_name
            read -r event_data
            
            # Execute callback
            execute_event_callback "$callback_script" "$event_data"
        fi
    done
}
subscribe_to_kafka() {
    local topic="$1"
    local callback_script="$2"
    local kafka_host="${eda_kafka_host:-localhost}"
    local kafka_port="${eda_kafka_port:-9092}"
    
    echo "Subscribing to Kafka topic: $topic"
    
    # Subscribe to Kafka topic
    kafka-console-consumer.sh --bootstrap-server "$kafka_host:$kafka_port" --topic "$topic" --from-beginning | while read -r event_data; do
        # Execute callback
        execute_event_callback "$callback_script" "$event_data"
    done
}
subscribe_to_rabbitmq() {
    local topic="$1"
    local callback_script="$2"
    local rabbitmq_host="${eda_rabbitmq_host:-localhost}"
    local rabbitmq_port="${eda_rabbitmq_port:-5672}"
    
    echo "Subscribing to RabbitMQ topic: $topic"
    
    # Subscribe to RabbitMQ topic
    amqp-consume -u "amqp://$rabbitmq_host:$rabbitmq_port" -q "$topic" | while read -r event_data; do
        # Execute callback
        execute_event_callback "$callback_script" "$event_data"
    done
}
subscribe_to_file() {
    local topic="$1"
    local callback_script="$2"
    local events_dir="${eda_events_dir:-/var/log/events}"
    local topic_dir="$events_dir/$topic"
    
    echo "Subscribing to file topic: $topic"
    
    # Monitor topic directory for new events
    inotifywait -m -e create "$topic_dir" | while read -r directory events filename; do
        if [[ -f "$topic_dir/$filename" ]]; then
            local event_data=$(cat "$topic_dir/$filename")
            # Execute callback
            execute_event_callback "$callback_script" "$event_data"
            # Remove processed event
            rm -f "$topic_dir/$filename"
        fi
    done
}
execute_event_callback() {
    local callback_script="$1"
    local event_data="$2"
    
    if [[ -f "$callback_script" ]]; then
        # Execute callback script with event data
        bash "$callback_script" "$event_data"
    else
        echo "Callback script not found: $callback_script"
    fi
}

Event Patterns and Routing

#!/bin/bash
Event patterns and routing
route_event() {
    local event_data="$1"
    local routing_file="${eda_routing_file:-/etc/event-driven/routing.conf}"
    
    # Extract event information
    local topic=$(echo "$event_data" | jq -r '.topic' 2>/dev/null)
    local event_type=$(echo "$event_data" | jq -r '.data.type' 2>/dev/null)
    
    if [[ -f "$routing_file" ]]; then
        while IFS='|' read -r pattern handler script; do
            if [[ "$topic" =~ $pattern ]] || [[ "$event_type" =~ $pattern ]]; then
                echo "Routing event to handler: $handler"
                execute_event_handler "$handler" "$script" "$event_data"
                return 0
            fi
        done < "$routing_file"
    fi
    
    echo "No route found for event: $topic"
    return 1
}
execute_event_handler() {
    local handler="$1"
    local script="$2"
    local event_data="$3"
    
    echo "Executing event handler: $handler"
    
    if [[ -f "$script" ]]; then
        # Execute handler script with event data
        bash "$script" "$event_data"
    else
        echo "Handler script not found: $script"
        return 1
    fi
}
pattern_matching() {
    local event_data="$1"
    local patterns_file="${eda_patterns_file:-/etc/event-driven/patterns.conf}"
    
    if [[ -f "$patterns_file" ]]; then
        while IFS='|' read -r pattern action script; do
            if echo "$event_data" | grep -q "$pattern"; then
                echo "Pattern matched: $pattern"
                execute_pattern_action "$action" "$script" "$event_data"
            fi
        done < "$patterns_file"
    fi
}
execute_pattern_action() {
    local action="$1"
    local script="$2"
    local event_data="$3"
    
    echo "Executing pattern action: $action"
    
    if [[ -f "$script" ]]; then
        # Execute action script with event data
        bash "$script" "$event_data"
    else
        echo "Action script not found: $script"
        return 1
    fi
}

Saga Pattern Implementation

#!/bin/bash
Saga pattern implementation
execute_saga() {
    local saga_name="$1"
    local saga_file="${eda_saga_file:-/etc/event-driven/sagas.conf}"
    
    if [[ -f "$saga_file" ]]; then
        while IFS='|' read -r name steps compensation; do
            if [[ "$name" == "$saga_name" ]]; then
                execute_saga_steps "$steps" "$compensation"
                return 0
            fi
        done < "$saga_file"
    fi
    
    echo "Saga not found: $saga_name"
    return 1
}
execute_saga_steps() {
    local steps="$1"
    local compensation="$2"
    local saga_log="/var/log/event-driven/sagas.log"
    
    echo "$(date '+%Y-%m-%d %H:%M:%S') - Starting saga execution" >> "$saga_log"
    
    # Parse and execute steps
    IFS=';' read -ra step_array <<< "$steps"
    local executed_steps=()
    
    for step in "${step_array[@]}"; do
        IFS=',' read -r service action data <<< "$step"
        
        echo "$(date '+%Y-%m-%d %H:%M:%S') - Executing step: $service.$action" >> "$saga_log"
        
        local result=$(execute_saga_step "$service" "$action" "$data")
        local exit_code=$?
        
        if [[ $exit_code -eq 0 ]]; then
            executed_steps+=("$step")
            echo "$(date '+%Y-%m-%d %H:%M:%S') - Step completed: $service.$action" >> "$saga_log"
        else
            echo "$(date '+%Y-%m-%d %H:%M:%S') - Step failed: $service.$action" >> "$saga_log"
            # Execute compensation
            execute_compensation "$compensation" "${executed_steps[@]}"
            return 1
        fi
    done
    
    echo "$(date '+%Y-%m-%d %H:%M:%S') - Saga completed successfully" >> "$saga_log"
    echo "✓ Saga completed: $saga_name"
}
execute_saga_step() {
    local service="$1"
    local action="$2"
    local data="$3"
    
    # Execute saga step
    local result=$(call_microservice "$service" "POST" "/saga/$action" "$data")
    return $?
}
execute_compensation() {
    local compensation="$1"
    shift
    local executed_steps=("$@")
    local saga_log="/var/log/event-driven/sagas.log"
    
    echo "$(date '+%Y-%m-%d %H:%M:%S') - Executing compensation" >> "$saga_log"
    
    # Execute compensation steps in reverse order
    for ((i=${#executed_steps[@]}-1; i>=0; i--)); do
        local step="${executed_steps[$i]}"
        IFS=',' read -r service action data <<< "$step"
        
        echo "$(date '+%Y-%m-%d %H:%M:%S') - Compensating step: $service.$action" >> "$saga_log"
        
        local result=$(execute_compensation_step "$service" "$action" "$data")
        local exit_code=$?
        
        if [[ $exit_code -eq 0 ]]; then
            echo "$(date '+%Y-%m-%d %H:%M:%S') - Compensation completed: $service.$action" >> "$saga_log"
        else
            echo "$(date '+%Y-%m-%d %H:%M:%S') - Compensation failed: $service.$action" >> "$saga_log"
        fi
    done
}
execute_compensation_step() {
    local service="$1"
    local action="$2"
    local data="$3"
    
    # Execute compensation step
    local result=$(call_microservice "$service" "POST" "/compensate/$action" "$data")
    return $?
}

CQRS Pattern Implementation

#!/bin/bash
CQRS pattern implementation
handle_command() {
    local command="$1"
    local command_data="$2"
    local command_handler="${eda_command_handler:-/etc/event-driven/commands.conf}"
    
    if [[ -f "$command_handler" ]]; then
        while IFS='|' read -r cmd_type handler_script; do
            if [[ "$command" == "$cmd_type" ]]; then
                echo "Handling command: $command"
                execute_command_handler "$handler_script" "$command_data"
                return 0
            fi
        done < "$command_handler"
    fi
    
    echo "No handler found for command: $command"
    return 1
}
execute_command_handler() {
    local handler_script="$1"
    local command_data="$2"
    
    if [[ -f "$handler_script" ]]; then
        # Execute command handler
        bash "$handler_script" "$command_data"
    else
        echo "Command handler not found: $handler_script"
        return 1
    fi
}
handle_query() {
    local query="$1"
    local query_params="$2"
    local query_handler="${eda_query_handler:-/etc/event-driven/queries.conf}"
    
    if [[ -f "$query_handler" ]]; then
        while IFS='|' read -r query_type handler_script; do
            if [[ "$query" == "$query_type" ]]; then
                echo "Handling query: $query"
                execute_query_handler "$handler_script" "$query_params"
                return 0
            fi
        done < "$query_handler"
    fi
    
    echo "No handler found for query: $query"
    return 1
}
execute_query_handler() {
    local handler_script="$1"
    local query_params="$2"
    
    if [[ -f "$handler_script" ]]; then
        # Execute query handler
        bash "$handler_script" "$query_params"
    else
        echo "Query handler not found: $handler_script"
        return 1
    fi
}

Event Monitoring and Analytics

#!/bin/bash
Event monitoring and analytics
monitor_events() {
    local monitoring_file="/var/log/event-driven/monitoring.json"
    
    # Collect event metrics
    local total_events=$(get_total_events)
    local published_events=$(get_published_events)
    local consumed_events=$(get_consumed_events)
    local failed_events=$(get_failed_events)
    local active_topics=$(get_active_topics)
    local average_processing_time=$(get_average_processing_time)
    
    # Generate monitoring report
    cat > "$monitoring_file" << EOF
{
    "timestamp": "$(date -Iseconds)",
    "total_events": $total_events,
    "published_events": $published_events,
    "consumed_events": $consumed_events,
    "failed_events": $failed_events,
    "success_rate": $(((consumed_events * 100) / published_events)),
    "active_topics": $active_topics,
    "average_processing_time_ms": $average_processing_time
}
EOF
    
    echo "✓ Event monitoring completed"
}
get_total_events() {
    local events_log="/var/log/event-driven/events.log"
    
    if [[ -f "$events_log" ]]; then
        wc -l < "$events_log"
    else
        echo "0"
    fi
}
get_published_events() {
    local events_log="/var/log/event-driven/events.log"
    
    if [[ -f "$events_log" ]]; then
        grep -c "PUBLISHED" "$events_log" 2>/dev/null || echo "0"
    else
        echo "0"
    fi
}
get_consumed_events() {
    local events_log="/var/log/event-driven/events.log"
    
    if [[ -f "$events_log" ]]; then
        grep -c "CONSUMED" "$events_log" 2>/dev/null || echo "0"
    else
        echo "0"
    fi
}
get_failed_events() {
    local events_log="/var/log/event-driven/events.log"
    
    if [[ -f "$events_log" ]]; then
        grep -c "FAILED" "$events_log" 2>/dev/null || echo "0"
    else
        echo "0"
    fi
}
get_active_topics() {
    local topics_file="${eda_topics_file:-/etc/event-driven/topics.conf}"
    
    if [[ -f "$topics_file" ]]; then
        wc -l < "$topics_file"
    else
        echo "0"
    fi
}
get_average_processing_time() {
    local processing_log="/var/log/event-driven/processing.log"
    
    if [[ -f "$processing_log" ]]; then
        local total_time=0
        local event_count=0
        
        while IFS= read -r log_line; do
            local processing_time=$(echo "$log_line" | grep -o 'processing_time=[0-9]*' | cut -d'=' -f2)
            if [[ -n "$processing_time" ]]; then
                total_time=$((total_time + processing_time))
                event_count=$((event_count + 1))
            fi
        done < "$processing_log"
        
        if [[ $event_count -gt 0 ]]; then
            echo $((total_time / event_count))
        else
            echo "0"
        fi
    else
        echo "0"
    fi
}

🎯 Real-World Configuration Examples

Complete Event-Driven Architecture Configuration

event-driven-config.tsk
event_driven_config:
  enabled: true
  publisher: true
  subscriber: true
  broker: redis
  topics: true
#event-driven: enabled
#eda-enabled: true
#eda-publisher: true
#eda-subscriber: true
#eda-broker: redis
#eda-topics: true
#eda-streaming: true
#eda-patterns: true
#eda-saga: true
#eda-cqrs: true
#eda-monitoring: true
#eda-tracing: true
#eda-config:
 publisher:
   enabled: true
   broker: redis
   redis_host: "localhost"
   redis_port: 6379
 subscriber:
   enabled: true
   broker: redis
   redis_host: "localhost"
   redis_port: 6379
 topics:
   enabled: true
   file: "/etc/event-driven/topics.conf"
   auto_create: true
 streaming:
   enabled: true
   batch_size: 100
   flush_interval: 60
 patterns:
   enabled: true
   file: "/etc/event-driven/patterns.conf"
   matching: "regex"
 saga:
   enabled: true
   file: "/etc/event-driven/sagas.conf"
   compensation: true
 cqrs:
   enabled: true
   command_handler: "/etc/event-driven/commands.conf"
   query_handler: "/etc/event-driven/queries.conf"
 monitoring:
   enabled: true
   interval: 60
   metrics:
     - "event_count"
     - "processing_time"
     - "error_rate"
 routing:
   enabled: true
   file: "/etc/event-driven/routing.conf"
   default_handler: "default"

Multi-Service Event Architecture

multi-service-event-architecture.tsk
multi_service_event_architecture:
  services:
    - name: user-service
      publisher: true
      subscriber: true
      topics: user-events
    - name: order-service
      publisher: true
      subscriber: true
      topics: order-events
    - name: payment-service
      publisher: true
      subscriber: true
      topics: payment-events
#eda-user-service: enabled
#eda-order-service: enabled
#eda-payment-service: enabled
#eda-config:
 services:
   user_service:
     enabled: true
     publisher: true
     subscriber: true
     topics: ["user-created", "user-updated", "user-deleted"]
   order_service:
     enabled: true
     publisher: true
     subscriber: true
     topics: ["order-created", "order-updated", "order-cancelled"]
   payment_service:
     enabled: true
     publisher: true
     subscriber: true
     topics: ["payment-processed", "payment-failed", "payment-refunded"]

🚨 Troubleshooting Event-Driven Architecture

Common Issues and Solutions

1. Event Publishing Issues

Debug event publishing
debug_event_publishing() {
    local topic="$1"
    local event_data="$2"
    echo "Debugging event publishing for topic: $topic"
    publish_event "$topic" "$event_data"
}

2. Event Subscription Issues

Debug event subscription
debug_event_subscription() {
    local topic="$1"
    local callback_script="$2"
    echo "Debugging event subscription for topic: $topic"
    subscribe_to_topic "$topic" "$callback_script"
}

🔒 Security Best Practices

Event-Driven Architecture Security Checklist

Security validation
validate_event_driven_security() {
    echo "Validating event-driven architecture security configuration..."
    # Check event encryption
    if [[ "${eda_encryption}" == "true" ]]; then
        echo "✓ Event encryption enabled"
    else
        echo "⚠ Event encryption not enabled"
    fi
    # Check event authentication
    if [[ "${eda_authentication}" == "true" ]]; then
        echo "✓ Event authentication enabled"
    else
        echo "⚠ Event authentication not enabled"
    fi
    # Check event authorization
    if [[ "${eda_authorization}" == "true" ]]; then
        echo "✓ Event authorization enabled"
    else
        echo "⚠ Event authorization not enabled"
    fi
}

📈 Performance Optimization Tips

Event-Driven Architecture Performance Checklist

Performance validation
validate_event_driven_performance() {
    echo "Validating event-driven architecture performance configuration..."
    # Check batch processing
    if [[ "${eda_batch_processing}" == "true" ]]; then
        echo "✓ Batch processing enabled"
    else
        echo "⚠ Batch processing not enabled"
    fi
    # Check event persistence
    if [[ "${eda_persistence}" == "true" ]]; then
        echo "✓ Event persistence enabled"
    else
        echo "⚠ Event persistence not enabled"
    fi
    # Check event streaming
    if [[ "${eda_streaming}" == "true" ]]; then
        echo "✓ Event streaming enabled"
    else
        echo "⚠ Event streaming not enabled"
    fi
}

🎯 Next Steps

- Event-Driven Optimization: Learn about advanced event-driven optimization - Event-Driven Visualization: Create event-driven visualization dashboards - Event-Driven Correlation: Implement event-driven correlation and alerting - Event-Driven Compliance: Set up event-driven compliance and auditing

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Event-driven architecture transforms your TuskLang configuration into an intelligent, reactive system. It brings modern reactive computing to your Bash applications with dynamic publishing, intelligent routing, and comprehensive event processing!