node-red-contrib-octocore/CHANGELOG.md

OctoCore implementation for node-red

# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [Unreleased]

## [0.0.17] - 2025-11-13

### Added

- **uns-publish**: Parallel message transmission for better performance
  - **Buffer Flush**: All buffered messages are now sent in parallel when connection is restored
  - **Batch Publishing**: All batch messages are now sent in parallel when batch is full
  - Performance improvement: ~10x faster for large batches (e.g., 1000 messages: ~100-200ms instead of 1-2s)
  - Status shows `publishing X msgs...` during parallel transmission

### Changed

- **uns-publish**: Improved batch publishing functionality
  - Changed default batch mode from "hybrid" to "size" for more predictable behavior
  - Batch now only publishes when full (size-based) by default
  - Simplified status display: Shows `batching (X/Y)` where X = current queue, Y = batch size
  - Removed confusing "sent" counter from status display
  - Original message timestamps are now preserved when batching (uses creation time, not send time)
  - Improved status update logic to prevent race conditions and flickering

### Fixed

- **uns-publish**: Fixed batch status display issues
  - Status no longer flickers between 0 and 1 when messages are added
  - Batch status is no longer overridden by connection status updates
  - Buffer and rate-limit status updates no longer interfere with batch status
  - Centralized status update function for consistency

- **uns-publish**: Fixed buffer configuration visibility
  - Buffer size fields are now properly hidden when buffering is disabled
  - Removed reference to non-existent `#buffer-config` element

## [0.0.16] - 2025-11-12

### Fixed

- **Node Loading**: Fixed incorrect node paths in `package.json` - all nodes now correctly reference `nodes/` directory
  - Changed from `"uns-publish.js"` to `"nodes/uns-publish.js"` for all 6 nodes
  - Fixed `main` field from `"uns-server.js"` to `"nodes/uns-server.js"`
  - Nodes now load correctly in Node-RED without "missing types" errors
  
- **Icon Paths**: Fixed icon references in HTML files to use correct relative paths
  - Changed from `'icon-primary-positive.png'` to `'icons/icon-primary-positive.png'` in all node HTML files
  - Icons now display correctly in Node-RED palette
  
- **Docker Configuration**: Improved volume mapping to prevent data loss
  - Changed `./examples:/data` to `./examples:/data/examples` to preserve Node-RED data directory
  - Removed unused `dev_data` volume definition
  
- **Documentation**: Fixed port inconsistencies across documentation files
  - Updated Makefile to show correct port 1886 (was 1885)
  - Updated `docs/manual-credentials.md` to use port 1886 (was 1885)
  - All documentation now consistently references port 1886
  
- **Markdown Formatting**: Fixed code block formatting in README.md
  - Corrected triple backticks (removed extra backticks in code examples)

### Removed

- **NATS JetStream Stream Nodes**: Moved to discard folder (not ready for production)
  - **`uns-stream-publisher`**: Moved to discard - Publish messages to JetStream streams with persistence and acknowledgment
    - **Stream Management:**
      - Auto-create streams if they don't exist
      - Configurable retention policies: Limits, Interest, WorkQueue
      - Storage options: File (persistent) or Memory (fast)
      - Replicas for high availability (1-5 replicas)
    - **Features:**
      - **Publish Acknowledgment**: Returns sequence number for each published message
      - **Deduplication**: Configurable duplicate window (e.g., "2m") prevents duplicate messages
      - **Headers Support**: Include custom headers with messages
      - **Subject Patterns**: Wildcard subject patterns (e.g., "sensor.*")
      - **Message Limits**: Configure max messages, max age, max bytes
    - **Configuration:**
      - Stream Name, Subject Pattern, Default Subject
      - Retention Policy (limits/interest/workqueue)
      - Max Messages (1-1,000,000), Max Age (e.g., "24h", "7d")
      - Max Bytes, Duplicate Window, Storage Type
    - **Output**: msg.stream, msg.sequence, msg.published, msg._duplicate
    - **Use Cases**: Event sourcing, audit logs, durable messaging, guaranteed delivery
  
  - **`uns-stream-consumer`**: Moved to discard - Consume messages from JetStream streams with explicit acknowledgment control
    - **Consumer Management:**
      - Auto-create durable consumers if they don't exist
      - Durable state persists across restarts
      - Subject filtering (e.g., "sensor.temperature")
      - Configurable consumer name for multiple instances
    - **Acknowledgment Modes:**
      - **Explicit**: Manual acknowledgment with msg.ack(), msg.nak(), msg.term(), msg.inProgress()
      - **All**: Automatic acknowledgment
      - **None**: No acknowledgment required
    - **Delivery Policies:**
      - **New Only**: Start from new messages (default)
      - **All**: Replay all messages from beginning
      - **Last**: Only last message
      - **By Start Sequence**: Replay from specific sequence number
      - **By Start Time**: Replay from specific timestamp
    - **Features:**
      - **Batch Processing**: Fetch multiple messages (1-100) in one request
      - **Redelivery**: Automatic retry with configurable max attempts (1-100)
      - **Max Ack Pending**: Control outstanding unacknowledged messages (1-10,000)
      - **Flow Control**: Backpressure handling with configurable heartbeat
      - **Acknowledgment Wait**: Configurable timeout (e.g., "30s")
      - **Idle Heartbeat**: Keep-alive for idle consumers (e.g., "5s")
    - **Output**: msg.payload, msg.stream, msg.consumer, msg.subject, msg.sequence, msg.timestamp, msg.redelivered, msg.pending, msg.headers
    - **Acknowledgment Functions:**
      ```javascript
      msg.ack()          // Acknowledge successful processing
      msg.nak(delay)     // Retry message (optional delay)
      msg.term()         // Terminate (no retry, mark as permanently failed)
      msg.inProgress()   // Extend ack wait time (still processing)
      ```
    - **Use Cases**: Reliable message processing, work queues, event replay, audit log consumption
  
  - **JetStream Benefits:**
    - **Persistence**: Messages survive server restarts
    - **Guaranteed Delivery**: At-least-once delivery semantics
    - **Replay**: Replay historical messages from any point
    - **Consumer Groups**: Multiple consumers share load
    - **High Availability**: Replicated streams for fault tolerance
    - **Message Ordering**: Guaranteed order within stream
  
  - **Integration**: Fully integrated with existing connection pooling and status management

- **NATS Key-Value Store Nodes**: Moved to discard folder (not ready for production)
  - **`uns-kv-get`**: Moved to discard - Retrieve, watch, and list keys from NATS KV buckets
    - **Operation Modes:**
      - **Get Value**: Retrieve single value by key (from config, msg.key, or msg.payload)
      - **Watch Key(s)**: Subscribe to key changes with wildcard support (e.g., `config.*`)
      - **List All Keys**: Get array of all keys in bucket
    - **Features:**
      - Auto-create buckets if they don't exist
      - Auto-parse JSON values (configurable)
      - Include revision history for GET operations
      - Ignore delete events in WATCH mode (configurable)
      - Real-time status updates showing watched keys
    - **Output:** msg.payload (value), msg.key, msg.revision, msg.created, msg.operation
    - **Use Cases:** Configuration storage, feature flags, session state, distributed cache, real-time sync
  - **`uns-kv-put`**: Moved to discard - Store, update, or delete values in NATS KV buckets
    - **Operations:**
      - **Put**: Create or update key (upsert)
      - **Create**: Create only if key doesn't exist (fails if exists)
      - **Update**: Update only if key exists (fails if not found)
      - **Delete**: Soft delete (mark as deleted, keep history)
      - **Purge**: Hard delete (remove all revisions)
    - **Features:**
      - Auto-stringify JSON objects (configurable)
      - TTL support (time-to-live for automatic expiration)
      - Key from config, msg.key, or msg.topic
      - Value from msg.payload, config, or msg.value
      - Detailed operation feedback (_created, _updated, _deleted, _purged flags)
    - **Use Cases:** Config management, feature flags, session storage, cache updates, state machines
  - **JetStream Integration:** Uses NATS JetStream for persistence and replication
  - **Connection Pooling:** Integrates with existing nats-server connection pool
  - **`uns-kv-bucket`**: Moved to discard - Manage NATS KV buckets
  - **`uns-health`**: Moved to discard - Health monitoring node

### Added

- **Message Validator Node (`uns-validator`)**: Advanced validation with JSON Schema, UNS spec, and custom rules
  - **Validation Types:**
    - **JSON Schema (Draft 7):** Full schema validation with type checking, required fields, ranges, patterns, formats (email, uri, date-time), enum values, array constraints (minItems, maxItems, uniqueItems)
    - **UNS Specification:** Validate UNS message format
      - Datatype validation (1-6: Integer, Float, Boolean, String, ByteArray, Object)
      - Value format matching (e.g., datatype 1 must have string representation of integer)
      - Timestamp validation (Unix or ISO 8601 format, range checking)
      - UUID v4 format validation for event IDs
    - **Custom Rules:** Visual rule editor with 4 types:
      - **Required**: Field must exist and not be null/undefined
      - **Range**: Number must be within range (e.g., `0:100`)
      - **Regex**: String must match pattern (e.g., `^[A-Z]+`)
      - **Custom**: JSONata expressions (e.g., `temperature > 0`)
    - **Combined Mode**: Run all validations (Schema + UNS + Custom) in sequence
  - **Actions on Validation Failure:**
    - **Reject**: Stop processing and emit error
    - **Warn**: Log warning but continue (message includes _validationErrors)
    - **Route to Output 2**: Invalid messages to output 2, valid to output 1
    - **Repair**: Attempt automatic fixes (type coercion, defaults, trimming)
  - **Repair Capabilities:**
    - Type coercion: "42" → 42, true → "true"
    - Missing required fields: Set to null
    - String truncation: Trim to maxLength
    - Repair count and flag in output (_repaired, _repairCount)
  - **Detailed Error Reporting:**
    - msg._valid (boolean)
    - msg._validationErrors (array of messages)
    - msg._validationDetails (detailed error objects with field, message, code)
  - **Dual Output Ports:** Valid (output 1), Invalid (output 2)
  - **Use Cases:** Data quality assurance, API validation, UNS compliance, error routing, data cleaning

- **Message Transformation Node (`uns-transform`)**: New node for data transformation, filtering, and validation
  - **Transform Modes:**
    - **JSONPath Query**: Extract specific fields using JSONPath syntax (e.g., `$.sensor.temperature`)
    - **Field Mapping**: Rename and restructure fields with visual mapping editor
    - **Pass-through**: No transformation, useful with conditional filtering
  - **Conditional Filtering**: Filter messages based on JSONata expressions or simple comparisons
    - Only matching messages pass to output 1, failed messages route to output 2 (if enabled)
    - Supports complex conditions like `payload > 50` or `$.status == "active"`
  - **Data Enrichment**: Automatically add metadata to messages
    - Auto-add timestamp (`_timestamp`) in ISO 8601 format
    - Auto-add Node ID (`_nodeId`) for traceability
    - Custom JSON fields injection
  - **Schema Validation**: Validate messages against JSON Schema
    - Configurable actions: Reject (error), Warn (continue), or Route to Output 2
    - Supports type checking, required fields, min/max values, string patterns
    - Detailed validation error messages
  - **Dual Output Ports**: Valid messages (output 1), Invalid/Filtered messages (output 2)
  - **Visual Status Indicators**: Shows transformation state (ready, transformed, filtered, invalid)
  - **Use Cases**: Clean sensor data, extract specific fields, validate data quality, enrich with metadata

- **Rate Limiting**: `uns-publish` now includes Token Bucket rate limiting to prevent message flooding
  - Enable via "Rate Limiting" checkbox in node configuration
  - **Token Bucket Algorithm**: Industry-standard rate limiting with burst support
  - Configurable rate limit (1-10,000 messages per window, default: 100)
  - Configurable time window (100-60,000 ms, default: 1,000 ms)
  - **Burst Allowance**: Allow temporary spikes (0-1,000 extra messages, default: 20)
  - **Three Actions on Limit Exceeded:**
    - **Drop (Silent)**: Discard excess messages without warnings
    - **Drop with Warning**: Discard and log warnings with statistics
    - **Delay (Queue & Throttle)**: Queue messages and send at allowed rate
  - Automatic token refill based on elapsed time
  - Visual status indicator shows queue size when rate limited
  - Debug logging shows token bucket state and dropped message counts
  - **Use Cases**: Protect against sensor malfunctions, prevent DoS, ensure fair resource usage

- **Batch Publishing**: `uns-publish` now supports grouping messages for efficient batch publishing
  - Enable via "Batch Publishing" checkbox in node configuration
  - Configurable batch size (1-1,000 messages, default: 100)
  - Configurable batch interval (100-60,000 ms, default: 1,000 ms)
  - Three batch modes:
    - **Hybrid (Default)**: Publish when size OR interval reached (whichever comes first)
    - **Size Only**: Publish only when batch size is reached
    - **Time Only**: Publish only when interval elapses
  - Visual status indicator shows batch progress (e.g., "batching (25/100)")
  - Significantly improves throughput for high-volume sensor data
  - Debug logging shows batch statistics (messages sent, failed, total)
  - Compatible with message buffering and auto-reply features

- **Auto-Reply Handler**: `uns-publish` now supports automatic request-reply pattern handling
  - Enable via "Auto-Reply Handler" checkbox in node configuration
  - Node now has 1 output port (previously 0) for message forwarding
  - Configurable reply timeout (100-60,000 ms, default: 5,000 ms)
  - Workflow: Input message → Forward to output → Process response → Send as NATS reply
  - Simplifies microservice patterns and eliminates manual reply-subject handling
  - Automatically cleans up pending reply timeouts on node close
  - Debug logging shows request forwarding and reply status
  - Use case: Build request-response services with minimal flow complexity

- **Manual UNS Datatype Override**: `uns-publish` now allows manual datatype selection for UNS Value format
  - New "UNS Datatype" dropdown that appears only when "UNS Value" format is selected
  - Options: Auto-Detect (default), Integer (1), Float (2), Boolean (3), String (4), Object (6)
  - Auto-Detect maintains backward compatibility with automatic type detection
  - Manual override useful for edge cases (e.g., forcing "42" to be a string instead of integer)
  - **Strict Type Validation**: Errors thrown if payload type doesn't match selected datatype
    - Example: Selecting "String (4)" but sending `42` (integer) → Error: "Datatype mismatch: Expected string but received integer"
    - Prevents silent type coercion bugs and ensures data integrity
    - Distinguishes between integer/float, array/object, and null values
  - Type conversion still applies: non-object types converted to string per UNS specification
  - Debug logging shows when manual override is active and validated

- **Enhanced Security & Authentication**: Complete security overhaul for NATS server connections
  - **Multiple Authentication Methods** (Dropdown Selection):
    - **No Authentication**: For local development or unsecured servers
    - **Username/Password**: Traditional authentication (default, backward compatible)
    - **Token Authentication**: Single authentication token for NATS server
    - **JWT Authentication**: NATS 2.x JSON Web Token with NKey seed
    - **NKey Authentication**: Cryptographic authentication using NKey seed
  - **TLS/SSL Encryption Support**:
    - Enable/disable TLS encryption with checkbox
    - **CA Certificate**: Server verification with custom CA certificate file
    - **Client Certificate**: Mutual TLS (mTLS) with client certificate
    - **Client Key**: Client private key for mTLS authentication
    - **Verify Server Certificate**: Optional certificate verification (enabled by default)
  - **Security Features**:
    - All credentials stored encrypted in Node-RED's secure credentials system
    - Automatic security warnings for production connections without TLS
    - JWT validation ensures both JWT token and NKey seed are provided
    - File-based certificate loading with path validation
    - Debug logging shows auth method and TLS status (with masked credentials)
  - **Backward Compatibility**:
    - Existing flows with username/password continue to work
    - New auth methods and TLS are opt-in
    - Flows need to re-configure to use new auth methods
  - **Production Ready**:
    - Follows NATS 2.x security best practices
    - Compatible with NATS JWT decentralized authentication
    - Supports industry-standard mTLS for zero-trust architectures
    - All credentials never visible in exported flows or version control

- **Message Buffering (Optional)**: Queue messages when connection is lost
  - Enable via checkbox in `uns-publish` node configuration
  - Configurable buffer size (10-10,000 messages, default: 1,000)
  - Three buffer modes: Drop Oldest (FIFO), Drop Newest, Reject on Full
  - Automatic flush when connection is restored
  - Buffer status visible in node status (e.g., "buffered (50/1000)")
  - Statistics: dropped message counter with warnings
  - Prevents data loss for critical sensor data during network interruptions
  - Disabled by default for backward compatibility

- **Connection Pooling & Shared Connections**: Intelligent connection management with reference counting
  - All nodes using the same `nats-server` config now share a single NATS connection
  - Automatic reference counting tracks which nodes are using the connection
  - `registerConnectionUser()` and `unregisterConnectionUser()` methods for connection lifecycle management
  - Automatic cleanup: Connection closes 30 seconds after last node unregisters
  - `getPoolStats()` method provides connection pool statistics (active users, node IDs, status)
  - Significantly reduces resource usage when multiple nodes use the same server
  - Prevents connection overhead and improves overall performance
  - Debug logging shows connection registration/unregistration events

### Changed

- **Specific Topic Publishing**: `uns-publish` now fully supports "Specific Topic" data format
  - Publish to any custom NATS subject
  - Automatically JSON-stringifies objects
  - Converts other types to strings
  - Works together with `uns-subscribe` specific_subject mode
  - Removed "(not ready yet)" label from UI

- **Specific Subject Auto-Parse**: `uns-subscribe` with `specific_subject` now automatically attempts JSON parsing
  - Tries to parse message as JSON object/array
  - Falls back to raw string if JSON parsing fails
  - Adds `_format` property to message: 'json' or 'string' for downstream processing
  - Silent fallback - no errors logged for non-JSON messages
  - Makes it easier to work with both JSON and plain text messages on the same subject

### Fixed

- **Message Logging**: Improved logging strategy to reduce noise in production
  - All message content logging (uns_value, event, reply, request/response) now requires `debug: true` flag
  - Prevents log flooding in high-frequency scenarios (100+ msg/sec)
  - Debug flag can be enabled per node in the node configuration
  - Fixed `uns-request` logging to properly show request and response payloads when debug enabled
  - Changed from `node.log(string, object)` to `node.log(string)` pattern for proper payload display
  - Errors and warnings are still always logged regardless of debug flag
  - Connection status changes are still always logged

- **Connection State Check**: Added connection status validation before publishing/requesting data
  - `nats-publish` now checks connection status before attempting to publish messages
  - `nats-request` now checks connection status before sending requests
  - `nats-health` now checks connection status before performing health checks
  - Prevents data loss and failed operations during connection interruptions
  - Returns clear error messages with reconnection status when not connected
  - Error code: `NOT_CONNECTED` with detailed reconnect attempt information

### Changed

- **Reconnection Logic**: Infinite reconnection attempts with exponential backoff
  - Set `reconnect: false`, `maxReconnectAttempts: 0`, and `waitOnFirstConnect: false` to fully disable NATS library's built-in reconnection
  - Custom application-layer reconnection with exponential backoff is now the sole reconnection mechanism
  - **Infinite retry attempts**: Server will continuously try to reconnect (no maximum limit)
  - Exponential backoff delays: 5s → 10s → 20s → 40s → 60s (stays at 60s forever)
  - Removed handling of NATS `reconnect` and `connect` events that would reset the attempt counter
  - Removed failsafe mechanism in `emitStatusChange()` that was causing duplicate reconnection attempts
  - Added explicit reconnection triggers in `disconnect` and `error` event handlers
  - Provides predictable reconnection behavior with proper attempt counting (1 → 2 → 3 → 4 → ... → ∞)
  - Fixes issue where `reconnectAttempts` counter would stay at 1 due to NATS library and failsafe mechanism resetting it
  - Status display now shows attempt count without maximum (e.g., "disconnected (5)" instead of "disconnected (5/10)")

## [0.0.15] - 2025-10-24

### Changed

- **Code Modernization**: Migration from `var` to `const`/`let` for modern ES6+ code
- **NATS.js API Update**: Migration from Callback API to Async Iterator API for future-proof implementation
- **Logging System**: Complete migration from `console.log()` to Node-RED's `node.log()` for professional logging (33 locations)
- **Performance**: StringCodec is now created once per node (instead of per request/message)
- **Datatype Conversion**: Refactored if-else chain to switch statement for better performance and readability

### Added

- **Error Code Constants**: Replaced magic strings with `NATS_ERROR_CODES` constants
- **Debug Flag**: `nats-request` node now has debug flag in HTML configuration
- **Enhanced Error Handling**: JSON.parse now with specific try-catch and detailed error context
- **Security**: Username is now masked in debug logs (in addition to password)
- **NPM Ignore**: Added `.npmignore` file to reduce package size and exclude development files
- **Example Flow**: New comprehensive demonstration flow with all OctoCore nodes

### Fixed

- **Strict Mode**: Fixed typo from `'use-strict'` to `'use strict'`
- **JSON Parse Safety**: Added missing try-catch blocks in `uns_value` message processing
- **Null Safety**: Replaced `toString()` with `String()` for null-safe conversion
- **Error Handling**: Improved error reporting with fallbacks for undefined values
- **Variable Declaration**: `send_message` is now correctly declared with `let` (Strict Mode compliant)

### Removed

- **Dead Code**: Removed unused `checkMSG.js` file
- **Commented Code**: Removed commented out `checkMSG` import
- **Unused Functions**: Removed unused `setStatusGreen` and `setStatusYellow` functions from `nats-request.js`
- **Unused Node**: Removed unregistered `nats-performance.js` file
- **Old Examples**: Removed 14 outdated example files, replaced with single comprehensive flow

### Documentation

- **Internationalization**: All German comments and documentation translated to English
  - Main node files: `nats-subscribe.js`, `nats-publish.js`, `nats-request.js`, `nats-server.js`, `nats-health.js`
  - Documentation files: All `/docs` markdown files translated to English
    - `timeout-handling.md`, `enhanced-status-display.md`, `credentials-setup.md`
    - `manual-credentials.md`, `performance-analysis.md`, `makefile-usage.md`
  - Ensures international accessibility and professional standards
- **Examples**: New comprehensive example flow (`examples/flows.json`) with documentation
  - Replaces 14 separate example files with single, editable flow
  - Includes examples for all node types: Publish, Subscribe, Request, Health
  - Auto-loaded with Docker Compose for easy development
  - Editable in Node-RED, changes persist to repository

### Security

- **Credential Masking**: Username is now masked in debug logs in addition to password
- **Safe Parsing**: JSON.parse protected with comprehensive error handling against crashes
- **Null-Safe**: String conversions are now null/undefined-safe

## [0.0.14] - 2025-09-10

### Changed

- Simplified node status: no uptime indicator when "connected"
- Consistent status text: publisher node shows just "connected"
- Updated node colors to `#57d297`
- Significantly reduced logging (errors/warnings only; optional debug)
- Debug options: added debug flag to `uns-publish` and `nats-server`
- Reconnect failsafe: automatically starts on `disconnected`
- Consistent status events: `addStatusListener` now emits an object initially

### Removed

- Removed stream nodes: `uns-stream-publisher`, `uns-stream-consumer`

### Fixed

- Fixed strict mode typo in `nats-publish.js`
- More robust validation: clear error when no server is selected

## [0.0.13] - 2025-08-22

### Added

- Jest test framework integration
- Prettier code formatting
- Modern ESLint configuration
- Comprehensive test coverage
- CHANGELOG.md for version tracking
- **NEW**: Enhanced Connection Health Node (`connection-health`) with advanced monitoring
- **NEW**: Enhanced timeout handling in `uns-request` node
- **NEW**: Improved error handling and validation
- **NEW**: Better connection monitoring and logging
- **NEW**: Makefile with comprehensive development commands
- **NEW**: Subscribe Node enhancements:
  - Payload now contains only the value (not full message)
  - Additional properties (datatype, id, name, timestamp) available as msg properties
  - Configurable topic field selection (NATS Subject, Datapoint ID, Name, Data Type)
  - Proper data type conversion for all UNS datatypes (1=Integer, 2=Float, 3=Boolean, 4=String, 5=JSON)
  - **NEW**: UNS Event format support for subscribing to events published by publish node
  - Event properties (id, type, startTime, endTime) available as msg properties
- **NEW**: Request Node enhancements:
  - Improved status indicators (grey "ready", yellow "requesting", orange for errors)
  - Better error handling with structured error messages in payload
  - Support for 503 Service Unavailable errors
  - Enhanced timeout handling with configurable options
- **NEW**: Connection Health Node features:
  - Extended server information (cluster, JetStream, TLS)
  - Connection metrics (latency, stability assessment)
  - Performance monitoring (throughput, bandwidth usage)
  - Connectivity tests (publish/subscribe, request/response validation)
  - Configurable thresholds for alerting
  - Health summary with overall status assessment
- **NEW**: NATS Stream Publisher Node (`uns-stream-publisher`) with WIP status
  - Auto-creates JetStream streams if they don't exist
  - Configurable stream settings (retention, storage, limits)
  - Real-time stream status monitoring
  - Support for headers and subject filtering
- **NEW**: NATS Stream Consumer Node (`uns-stream-consumer`) with WIP status
  - Auto-creates JetStream consumers if they don't exist
  - Manual acknowledgment functions (ack, nak, term, inProgress)
  - Configurable batch processing
  - Subject filtering and delivery policies
- **NEW**: Enhanced UNS Publish Node with improved datatype detection
  - Automatic distinction between Integer (datatype 1) and Float (datatype 2)
  - Comprehensive logging for debugging
  - Better error handling and validation

### Changed

- Updated ESLint to version 8.x (latest stable)
- Updated all dev dependencies to latest versions
- Simplified Node.js engine requirements to >=18.0.0
- Fixed typo in package.json description
- Enhanced NATS server connection options with better timeout handling
- Improved error messages and validation across all nodes
- **CHANGED**: Subscribe Node payload structure - now only value in payload, rest as msg properties
- **CHANGED**: Request Node status behavior - improved visual feedback with color-coded status indicators
- **CHANGED**: Health Node renamed to "connection-health" in UI for better clarity
- **CHANGED**: Enhanced error handling across all nodes with structured error messages
- **CHANGED**: UNS Publish Node now correctly identifies Integer vs Float datatypes
- **CHANGED**: Added extensive logging to UNS Publish Node for better debugging
- **CHANGED**: Stream Publisher Node includes WIP status indicators

### Fixed

- Typo in package.json: "impelentation" → "implementation"
- **FIXED**: Server configuration validation to prevent null reference errors
- **FIXED**: Duplicate break statement in nats-subscribe.js
- **FIXED**: Better error handling for missing server configurations
- **FIXED**: Subscribe Node data type conversion for all UNS datatypes
- **FIXED**: Request Node status persistence issues - now properly resets after operations
- **FIXED**: Health Node latency measurement using correct NATS.js flush() method
- **FIXED**: Request Node 503 error handling with proper status indication
- **FIXED**: Subscribe Node topic field configuration persistence
- **FIXED**: UNS Publish Node datatype detection for numbers (Integer vs Float)
- **FIXED**: Stream Publisher Node header handling compatibility with NATS.js
- **FIXED**: Better error messages for JetStream availability issues

## [Unreleased]

### Added

- Future features and improvements

### Changed

- Future changes

### Fixed

- Future bug fixes

## [0.0.12] - 2024-01-XX

### Added

- Initial release of node-red-contrib-octocore
- NATS publish node
- NATS subscribe node
- NATS request node
- NATS server configuration node

### Features

- Support for UNS Value data format
- Support for RAW Value data format
- Support for Reply data format
- Support for Specific Topic data format
- Support for Event data format