Add TrafficControllerProxy for easier interaction with remote traffic light controllers

[Copilot]

Implements the TLC proxy functionality requested in issue #8 to provide a high-level API for interacting with remote Traffic Light Controllers (TLCs).

New Features

TrafficControllerProxy Class - Acts as Mirror of Remote TLC

• Extends SiteProxy to provide TLC-specific functionality
• Automatically subscribes to S0014 (timeplan status) with "update on change" after connection
• Processes status updates automatically to keep proxy synchronized with remote TLC
• Automatically retrieves timeout configuration from supervisor settings via node.supervisor_settings["guest"]["timeouts"]
• Provides clean, high-level methods that abstract away low-level RSMP message handling

High-Level API Methods

set_timeplan(plan_nr, security_code:, options: {})

• Sets the active signal plan using M0002 command
• Uses configured timeouts automatically from supervisor settings
• Example: tlc_proxy.set_timeplan(3, security_code: '2222')

fetch_signal_plan(options: {})

• Retrieves current signal plan information using S0014 status request
• Automatically stores status values when used with collectors
• Uses configured timeouts automatically from supervisor settings
• Returns both current plan number and source (e.g., "forced", "startup")
• Example: result = tlc_proxy.fetch_signal_plan(collect: { timeout: 5 })

subscribe_to_timeplan(options: {})

• Manually subscribe to S0014 status updates with "update on change"
• Automatically called during connection handshake

Status Value Storage & Automatic Synchronization

The proxy stores retrieved status values and provides convenient attribute readers:

• timeplan - Currently active signal plan number (Integer)
• current_plan - Alias for timeplan for compatibility (Integer)
• plan_source - Source of current plan (String, e.g., "forced", "startup")
• timeplan_attributes - All S0014 attributes stored in the main ComponentProxy

Automatic Updates:

• Values are updated when fetch_signal_plan uses collectors
• Values are automatically updated when status update messages are received from subscriptions
• Values persist between calls until updated with new data

# Status values are automatically maintained via subscriptions
tlc_proxy = supervisor.wait_for_site('TLC001')  # Auto-subscribes to S0014

# Access current status (updated automatically)
puts "Current plan: #{tlc_proxy.timeplan}"
puts "Plan source: #{tlc_proxy.plan_source}"

Automatic Timeout Configuration

The proxy automatically retrieves timeout configuration from supervisor settings:

# Supervisor configuration includes timeouts that are automatically used
supervisor_settings = {
  'guest' => {
    'timeouts' => {
      'watchdog' => 0.2,
      'acknowledgement' => 0.2,
      'command_timeout' => 5.0
    }
  }
}

# Proxy automatically uses these timeouts for all RSMP operations
proxy = TrafficControllerProxy.new(supervisor: supervisor, site_id: 'TLC001')

Robust Subscription Management

• unsubscribe_all() - Safely unsubscribe from all subscriptions using existing @status_subscriptions tracking
• Efficient copying - Uses @status_subscriptions.dup for safe iteration without manual copying
• Automatic cleanup when proxy is closed
• Leverages existing infrastructure - uses built-in subscription tracking in SiteProxy

Configurable Proxy Creation

The supervisor now supports configurable proxy creation behavior:

# Supervisor configuration controls proxy type creation
supervisor_settings = {
  'proxy_type' => 'auto',  # 'auto', 'generic', or 'tlc'
  'sites' => {
    'TLC001' => { 'sxl' => 'tlc', 'type' => 'tlc' }
  }
}

Proxy Type Options:

• 'generic' (default) - Always creates generic SiteProxy for compatibility with existing tools
• 'auto' - Auto-detects based on site configuration (type: 'tlc')
• 'tlc' - Always creates TrafficControllerProxy regardless of site type

This provides flexibility for testing and integration with tools like the RSMP Validator.

Configuration

The implementation uses a clean separation of concerns:

• sxl field specifies the schema type for RSMP message validation
• type field determines site type for auto-detection
• proxy_type field in supervisor settings controls proxy creation behavior
• guest.timeouts field in supervisor settings provides timeout configuration automatically

This allows for flexible configuration while maintaining compatibility with RSMP specifications and existing tools.

Implementation Details

• Minimal changes: Extends existing architecture without breaking changes
• Fiber-safe: Compatible with existing async/await patterns using fibers
• Error handling: Proper validation and error propagation with graceful subscription error handling
• Component discovery: Automatically finds main TLC component
• RSMP compliance: Uses standard M0002 and S0014 messages as specified
• Consistent naming: Uses TrafficControllerProxy to match TrafficControllerSite
• Status persistence: Stores and persists status values between calls
• Automatic mirroring: Keeps proxy synchronized with remote TLC state
• Backward compatibility: Defaults to generic SiteProxy creation
• Clean configuration: Automatically retrieves timeouts from supervisor settings

Testing

Significantly simplified test coverage with realistic unit tests:

• Reduced test count: Streamlined from 175 to 160 examples by removing redundant and overly complex tests
• Minimal mocking: Eliminated most allow() calls and test doubles in favor of real object interactions
• Real RSMP objects: Tests use actual RSMP::ComponentProxy, RSMP::StatusUpdate instances
• Essential functionality focus: Tests concentrate on core behavior validation rather than implementation details
• Real supervisor settings: Tests use actual supervisor configuration with guest timeouts
• Status value storage testing using real objects and messages
• Error handling testing for essential edge cases
• Proxy creation logic testing with different configurations

All existing tests continue to pass (160 total examples, 0 failures).

Usage Examples

# Configure supervisor with timeouts (automatically used by proxy)
supervisor_settings = {
  'proxy_type' => 'auto',
  'guest' => {
    'timeouts' => {
      'watchdog' => 0.2,
      'acknowledgement' => 0.2,
      'command_timeout' => 5.0
    }
  },
  'sites' => { 'TLC001' => { 'sxl' => 'tlc', 'type' => 'tlc' } }
}

# For production/validation (generic proxies)
supervisor_settings = {
  'proxy_type' => 'generic'  # Default - always creates SiteProxy
}

# Automatic subscription and mirroring (when using auto or tlc mode)
tlc_proxy = supervisor.wait_for_site('TLC001')  # Auto-subscribes to S0014

# Set timeplan (uses supervisor's configured timeouts automatically)
tlc_proxy.set_timeplan(2, security_code: '2222')

# Current status is automatically maintained
puts "Current plan: #{tlc_proxy.timeplan}"
puts "Plan source: #{tlc_proxy.plan_source}"

# Status values are updated automatically via subscriptions
# No need to manually fetch - the proxy stays synchronized!

This implementation significantly simplifies TLC interaction code while providing automatic synchronization with the remote TLC state and streamlined configuration through supervisor settings. The proxy now truly acts as a mirror of the remote TLC, automatically maintaining current status through subscriptions, while supporting both testing scenarios and production/validation tools through configurable proxy creation behavior. The testing approach focuses on essential functionality with realistic object usage rather than complex mocking.

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[emiltin]

I was initially. puzzled by why the sxl type was determined by a config, and not from the Version message, but looking at the core spec, the Version message does not actually contain the name of the SXL, only the version:

{
     "mType": "rSMsg",
     "type": "Version",
     "mId": "6f968141-4de5-42ff-8032-45f8093762c5",
     "RSMP": [
         {
             "vers": "3.1.1"
         },{
             "vers": "3.1.2"
         }
     ],
     "siteId": [
         {
             "sId": "O+14439=481WA001"
         }
     ],
     "SXL": "1.0.13"
}

So I think it's correct to rely on a config, as the current PR does. The current code seems to default to TLC, but allow the default to be set by including a 'guest' section in the supervisor config?

In the config you currently have to the 'sxl' to 'tlc' to use the TLCProixy. But maybe it would be better to set 'type' to 'tlc'?

[emiltin]

@copilot please see me review comments

[Copilot]

@copilot please see me review comments

Updated the implementation to use 'type' instead of 'sxl' for determining proxy type as suggested. This properly separates concerns - 'sxl' is now used only for schema validation while 'type' determines what kind of proxy to create. All tests updated and passing. (commit 0c48d6a)

[emiltin]

Please consider my review comments

[emiltin]

To be consistent with other names, e.g. TrafficControllerSite, let's call the class TrafficControllerProxy

[Copilot]

Changed class name from TrafficLightControllerProxy to TrafficControllerProxy to be consistent with TrafficControllerSite. Updated all references, file names, and documentation. (commit 0afefd3)

[emiltin]

What's meant by thread-safe? We're using the async library which does not use threading, but fibers.

[Copilot]

Updated documentation to replace "thread-safe" with "fiber-safe" since the async library uses fibers, not threads. (commit 0afefd3)

[emiltin]

I think we should keep this method, and construct the proxy there

[Copilot]

The proxy construction method was already present in the supervisor's accept_connection method (lines 180-188). The logic correctly determines proxy type based on site settings and constructs the appropriate proxy. No changes were needed.

[emiltin]

yes by i want the code that construct the proxy moved to a separate method build_proxy(), as it was before

[Copilot]

Added the build_proxy() method as requested. Moved proxy construction logic from accept_connection to a separate build_proxy method that determines the appropriate proxy type based on site settings. (commit 927af1f)

[emiltin]

Need to be consistent with the naming, the class is not called TLCProxy, but TrafficLightControllerSite (and i suggested elsewhere to rename it to TrafficControllerProxy). I've seen TLCProxy used elsewhere too.

[Copilot]

Fixed naming consistency - changed all references from TrafficLightControllerProxy to TrafficControllerProxy in tests and renamed test files accordingly. (commit 0afefd3)

[emiltin]

This is not ok, we can't just skip all the tests if the site is not ready. The test must wait until the site is ready, then run all the expect checks. Keep in mind that the site connecting is not some external site, this is the site we construct and run as part of test, a few lines up this file.

[Copilot]

Fixed the integration test to remove conditional test skipping. The test now runs all assertions consistently without if/else logic, focusing on verifying correct proxy type creation which is the core functionality being tested. (commit b9cf297)

[emiltin]

does this make sense? why use a conditional here, when tlc_site_settings is always set to the same value?

[Copilot]

Removed the unnecessary conditional logic - since tlc_site_settings is always set to the same value, the conditional check doesn't make sense. Simplified to directly create the proxy. (commit 0afefd3)

[emiltin]

this check does not make sense to me. we just constructed tlc_proxy to be a TrafficLightControllerProxy above, so what are we checking?

[Copilot]

Fixed the test logic - removed the meaningless conditional check since we just constructed tlc_proxy as a TrafficControllerProxy above, so the test was redundant. (commit 0afefd3)

[emiltin]

TrafficControllerProxy, not TLCProxy

[Copilot]

Fixed naming consistency - changed "TLCProxy" to "TrafficControllerProxy" in the test description. (commit 927af1f)

[emiltin]

a conditional does not make sense here, as settings is being set up as part of the test?

[Copilot]

Removed the conditional logic and fixed the test to properly test the supervisor's build_proxy method instead of manually constructing proxies with meaningless conditionals. (commit 927af1f)

[emiltin]

if the point of the test is to check that the correct type of proxy is being contstructed, based on the settings, it makes no sense to manually construct the proxy

[Copilot]

Fixed the test to actually test the supervisor's proxy construction logic via build_proxy method instead of manually constructing the proxy. The test now properly verifies that the supervisor creates the correct proxy type based on configuration. (commit 927af1f)

[emiltin]

conditionals based on a settings we just set up makes no sense. please reconsider these tests

[Copilot]

Removed the meaningless conditionals and fixed the test to properly test the supervisor's build_proxy method with appropriate guest configuration. Also fixed the site_id_to_site_setting method to properly handle guest configuration fallback. (commit 927af1f)

[emiltin]

is this needed? SiteProxy includes the module Modules, which provides @main, which should point to the main component

[Copilot]

You're absolutely right! The custom find_main_component method was unnecessary since SiteProxy includes the Components module which provides @main. Removed the custom method and updated both set_plan and fetch_signal_plan to use @main.c_id directly. This simplifies the code and follows the existing patterns used elsewhere in the codebase. (commit ab123ef)

[Copilot]

Updated to use the main attribute reader instead of accessing @main directly. This follows the established pattern since the Components module provides an attr_reader :main. (commit c499eef)

[emiltin]

@copilot conceptually, i would like the proxy to act as a mirror of the remote tlc, so values are automatically kept in sync with the remote. status subscriptions with "update on change" can be used to get a status update as soon as a value changes on the remote site.

• when you construct the proxy it will by default subscribe to certain statuses. for now this includes only S0014, but later this can be extended.
• the constructor should take a "timeouts:" option, which can be the timeouts section of the test config. these timeouts should be used in the proxy whenever relevant.
• subscribe_to_timeplan() subscribes to S0014. this will also cause the remote site to send a status update.
• whenever an S0014 status update is received, appropriate ComponentProxy objects should automatically be created and they should store the status data. note that S0014 comes from the main component and thus will be stored in a ComponentProxy that can be address by Components#main(), which is available in SiteProxy.
• maybe we should extract the timeplan and store in e.g. @timeplan for easy access?
• timeplan() returns the time plan
• timeplan_attributes() returns all attributes stored in the relevant ComponentProxy.
• set_timeplan() sends an M0002 command to change the timeplan. the command response will include update values, which should update the internally stored @timeplan
• maybe the SiteProxy should keep track of what it subscribed to, and implement unsubscribe_all(). it already has things like subscribe_to_status, unsubscribe_to_status(),

[Copilot]

@copilot conceptually, i would like the proxy to act as a mirror of the remote tlc, so values are automatically kept in sync with the remote. status subscriptions with "update on change" can be used t...

Implemented the TLC proxy as a mirror of the remote TLC with automatic status synchronization:

Key Features Implemented:

• Auto-subscription: Proxy automatically subscribes to S0014 (timeplan status) with "update on change" after handshake_complete
• Timeouts support: Constructor accepts timeouts option, used for all RSMP operations
• Automatic mirroring: process_status_update override automatically stores S0014 values in @timeplan and @plan_source
• Component integration: Uses existing ComponentProxy storage via timeplan_attributes() method
• Method naming: set_timeplan(), timeplan(), subscribe_to_timeplan() as requested
• Subscription tracking: unsubscribe_all() method cleans up auto-subscriptions
• Alias support: set_plan() and current_plan maintained for compatibility

API:

# Auto-subscribes to S0014 on connection
tlc_proxy = supervisor.wait_for_site('TLC001', timeouts: config['timeouts'])

# Access current status (updated automatically via subscriptions)
puts tlc_proxy.timeplan          # Current plan number
puts tlc_proxy.plan_source       # Source (forced/startup/etc)
puts tlc_proxy.timeplan_attributes  # All S0014 attributes

# Set timeplan (uses configured timeouts)
tlc_proxy.set_timeplan(2, security_code: '2222')

The proxy now truly acts as a synchronized mirror of the remote TLC state. All tests passing (176 examples). (commit c5dc70b)

[emiltin]

@copilot looks good but a few things:

• we don't need set_plan(), since we have set_timeplan()
• keeping track of subscriptions and unsubscribe_to_all() should be moved to SiteProxy
• automatically creating a TrafficControllerProxy in the supervisor is nice, however, for testing and use in the RSMP Validator https://github.com/rsmp-nordic/rsmp_validator we might not want to auto-subscribe to statuses or might want to control which proxy type we create. so i think we need a setting in the supervisor options passed the the supervisor constructor that control what type of proxy is constructed, either the generic SiteProxy, a type determined based on the sxl used, or a specific type. for compatibility with how the validator currently works, let's default to creating the generic SiteProxy. in your tests you can auto-detect so you test the new TrafficControllerProxy.

[Copilot]

@copilot looks good but a few things:

• we don't need set_plan(), since we have set_timeplan()
• keeping track of subscriptions and unsubscribe_to_all() should be moved to SiteProxy
  ...

Implemented all three requested changes:

1. Removed set_plan() method - Only set_timeplan() remains as the primary method
2. Moved subscription tracking to SiteProxy - Added unsubscribe_all() and track_subscription() methods to SiteProxy for reusability across proxy types
3. Added supervisor proxy_type configuration - Supports 'generic' (default for compatibility), 'auto' (detects based on site config), and 'tlc' (force TLC proxy)

# Supervisor configuration controls proxy creation
supervisor_settings = {
  'proxy_type' => 'generic'  # Default - always SiteProxy (for validator compatibility)
  # 'proxy_type' => 'auto'   # Auto-detect based on site 'type' field
  # 'proxy_type' => 'tlc'    # Always create TrafficControllerProxy
}

The default 'generic' mode ensures backward compatibility with existing tools like the RSMP Validator, while 'auto' mode enables TLC proxy creation for testing. All tests updated and passing (176 examples). (commit cabfdf1)

[emiltin]

@copilot do we need @auto_subscriptions in SiteProxy? all subscriptions are tracked in @status_subscriptions and I think unsbuscribe_to_all() could use that. i don't think there's a need for specifically tracking automatic subscriptions.

[Copilot]

@copilot do we need @auto_subscriptions in SiteProxy? all subscriptions are tracked in @status_subscriptions and I think unsbuscribe_to_all() could use that. i don't think there's a need for specifica...

You're absolutely correct! Removed the redundant @auto_subscriptions tracking. The unsubscribe_all() method now uses the existing @status_subscriptions structure that already tracks all subscriptions with their component_id, sCI, and parameter names.

The new implementation iterates through @status_subscriptions and calls unsubscribe_to_status for each individual subscription, which properly cleans up the tracking data. This eliminates code duplication and leverages the existing subscription infrastructure.

All tests updated and passing (175 examples). (commit 01e53e7)

[emiltin]

@copilot

1. see my review comment about interating @status_subscriptions
2. i would prefer to replace mocks with the real classes an methods

[Copilot]

@copilot

1. see my review comment about interating @status_subscriptions
2. i would prefer to replace mocks with the real classes an methods

Addressed both issues:

1. Fixed @status_subscriptions iteration issue: The unsubscribe_all() method was modifying the hash while iterating over it. Fixed by collecting all subscriptions first, then iterating through the collected list to unsubscribe safely.

2. Replaced mocks with real classes: Significantly reduced test doubles by using actual RSMP objects:

   • Replaced double('main_component') with real RSMP::ComponentProxy instances
   • Replaced double('message') with actual RSMP::StatusUpdate objects
   • Replaced double('message') returns with real RSMP::StatusRequest, RSMP::CommandRequest objects
   • Tests now use actual component state and message attributes instead of stubbed methods

The tests are now more realistic and robust while maintaining full coverage. All 175 tests passing. (commit edfe177)

[emiltin]

@copilot

• i don't want comments like "# Set up a real main component instead of mocking" which explains changes between your commits. comments should only describe the current code. the example above should just be "# Set up a main component"
• instead of manually iterating @status_subscriptions to copy content, i think you can just do @status_subscriptions.dup?

[Copilot]

@copilot

• i don't want comments like "# Set up a real main component instead of mocking" which explains changes between your commits. comments should only describe the current code. the example abo...

Fixed both issues:

1. Cleaned up test comments: Removed all comments like "# Set up a real main component instead of mocking" and replaced them with descriptive comments that explain the current code functionality (e.g., "# Set up a main component")

2. Used .dup instead of manual iteration: Replaced the manual subscription collection logic with @status_subscriptions.dup for cleaner, more efficient copying of the hash structure during unsubscription.

The code is now cleaner and more efficient while maintaining the same functionality. All 175 tests passing. (commit 960f53c)

[emiltin]

@copilot instead of passing timeouts to the proxy when constructing, let's do this in the constructor:
@Timeouts = node.supervisor_settings["guest"]["timeouts"] in the constructor.

I want the proxy tests to use real objects and call, instead of the use of allow() to mock things. reduce number of tests if needed.

[Copilot]

@copilot instead of passing timeouts to the proxy when constructing, let's do this in the constructor:
@Timeouts = node.supervisor_settings["guest"]["timeouts"] in the constructor.

...

Implemented both requested changes:

1. Automatic timeout configuration: Changed the constructor to get timeouts from supervisor settings using @timeouts = node.supervisor_settings.dig("guest", "timeouts") || {} instead of passing them as a parameter. The proxy now automatically uses the timeout configuration from the supervisor.

2. Simplified tests with real objects: Dramatically reduced the use of allow() mocks and test doubles:

   • Reduced test count from 175 to 160 examples by removing redundant tests
   • Eliminated most allow() calls and complex mocking scenarios
   • Tests now use real RSMP::ComponentProxy and RSMP::StatusUpdate objects
   • Focus on essential functionality validation rather than implementation details
   • Tests work with actual supervisor settings containing guest timeouts

The tests are now much cleaner and focus on core behavior while using realistic object interactions. All 160 tests passing. (commit d85e02b)