Swiss Ephemeris Ffi Laravel Package

Getting Started

Minimal Steps

1. Installation:

   composer require jayeshmepani/swiss-ephemeris-ffi
   

   Ensure your php.ini has ffi.enable=true and PHP 8.3+.

2. Basic Usage:

   use SwissEph\FFI\SwissEphFFI;
   
   $sweph = new SwissEphFFI();
   $jd = $sweph->swe_julday(2000, 1, 1, 12.0, SwissEphFFI::SE_GREG_CAL);
   $xx = $sweph->getFFI()->new("double[6]");
   $serr = $sweph->getFFI()->new("char[256]");
   
   $result = $sweph->swe_calc_ut($jd, SwissEphFFI::SE_SUN, SwissEphFFI::SEFLG_SPEED, $xx, $serr);
   

3. Laravel Facade:

   use SwissEph\FFI\Facades\SwissEph;
   
   $sunPos = SwissEph::swe_calc_ut($jd, SwissEph::SE_SUN, SwissEph::SEFLG_SPEED, $xx, $serr);
   

Where to Look First

• API Reference: Documentation for function signatures and constants.
• Laravel Setup: Check config/swiss-ephemeris.php for custom paths or ephemeris file locations.
• Ephemeris Files: Verify storage/app/swisseph/ contains .se1 files (published via php artisan vendor:publish --provider="SwissEph\FFI\SwissEphFFIServiceProvider").

First Use Case

Calculate planetary positions for a horoscope:

$jd = SwissEph::swe_julday(1990, 5, 17, 12.0, SwissEph::SE_GREG_CAL);
$xx = SwissEph::getFFI()->new("double[6]");
$serr = SwissEph::getFFI()->new("char[256]");

$sunPos = SwissEph::swe_calc_ut($jd, SwissEph::SE_SUN, 0, $xx, $serr);
$moonPos = SwissEph::swe_calc_ut($jd, SwissEph::SE_MOON, 0, $xx, $serr);

Implementation Patterns

Core Workflows

1. Initialization:

   • Use the facade for Laravel:

     SwissEph::setLibraryPath('/custom/path/to/libswisseph.so');
     

   • Singleton Note: Paths set after initialization may fail. Set paths before instantiating.

2. Date Handling:

   • Convert Gregorian dates to Julian Day (JD) first:

     $jd = SwissEph::swe_julday($year, $month, $day, $hour, SwissEph::SE_GREG_CAL);
     

3. Planetary Calculations:

   • Use swe_calc_ut for positions/speeds:

     $flags = SwissEph::SEFLG_SPEED | SwissEph::SEFLG_J2000;
     $xx = SwissEph::getFFI()->new("double[6]");
     $result = SwissEph::swe_calc_ut($jd, SwissEph::SE_MARS, $flags, $xx, $serr);
     

4. House Systems:

   • Calculate houses with swe_house_pos:

     $house = SwissEph::swe_house_pos($jd, SwissEph::SEFLG_SWIEPH, SwissEph::SE_PLACIDUS, $lat, $lon, $xx);
     

5. Error Handling:

   • Check return codes and $serr buffer:

     if ($result < 0) {
         throw new \RuntimeException(SwissEph::getFFI()->string($serr));
     }
     

Integration Tips

• Laravel Service Providers: Bind the FFI instance in AppServiceProvider:

  public function register()
  {
      $this->app->singleton(SwissEphFFI::class, function ($app) {
          return new SwissEphFFI($app['config']['swiss-ephemeris.library_path']);
      });
  }
  

• Caching:

  • Cache JD conversions or ephemeris results in Laravel’s cache:

    $jd = Cache::remember("jd_{$year}_{$month}_{$day}", now()->addHours(1), function () use ($year, $month, $day) {
        return SwissEph::swe_julday($year, $month, $day, 0, SwissEph::SE_GREG_CAL);
    });
    

• Batch Processing:

  • Use swe_calc_ut in loops for multiple planets:

    $planets = [SwissEph::SE_MERCURY, SwissEph::SE_VENUS, SwissEph::SE_EARTH];
    foreach ($planets as $planet) {
        $xx = SwissEph::getFFI()->new("double[6]");
        SwissEph::swe_calc_ut($jd, $planet, 0, $xx, $serr);
        // Process $xx[0] (longitude), $xx[1] (latitude), etc.
    }
    

• Asteroids/Comets:

  • Use swe_calc_ut with SE_AST_* constants:

    $asteroid = SwissEph::SE_AST_433; // Eros
    $xx = SwissEph::getFFI()->new("double[6]");
    SwissEph::swe_calc_ut($jd, $asteroid, 0, $xx, $serr);
    

Laravel-Specific Patterns

1. Publish Ephemeris Files:

   php artisan vendor:publish --provider="SwissEph\FFI\SwissEphFFIServiceProvider" --tag="ephe-files"
   

   Files land in storage/app/swisseph/.

2. Config Overrides:

   // config/swiss-ephemeris.php
   'library_path' => env('SWISS_EPHEMERIS_LIBRARY_PATH', null),
   'ephe_path' => storage_path('app/swisseph'),
   

3. Queue Jobs:

   • Offload heavy calculations to queues (FFI is not thread-safe):

     dispatch(new CalculateHoroscopeJob($jd, $lat, $lon));
     

Gotchas and Tips

Pitfalls

1. Singleton Behavior:

   • Issue: Setting setLibraryPath() after instantiation may fail silently.
   • Fix: Initialize with the correct path:

     $sweph = new SwissEphFFI('/custom/path/to/libswisseph.so');
     

2. FFI Memory Management:

   • Issue: FFI buffers (double[6], char[256]) must be reallocated for each call or reused carefully.
   • Fix: Reuse buffers in loops or allocate fresh ones:

     $xx = SwissEph::getFFI()->new("double[6]"); // Allocate once and reuse
     

3. Thread Safety:

   • Issue: FFI is not thread-safe. Concurrent calls from multiple threads/processes may corrupt memory.
   • Fix: Use Laravel queues or ensure single-threaded execution.

4. Ephemeris File Paths:

   • Issue: Missing .se1 files cause swe_calc_ut to return -1 with error "no ephemeris file".
   • Fix: Publish files or set ephe_path in config:

     SwissEph::setEphePath('/custom/ephe/path');
     

5. Date/Time Precision:

   • Issue: Floating-point hours (e.g., 12.5 for 12:30 PM) must use . not , in some locales.
   • Fix: Use 12.5 (not 12,5) or enforce setlocale(LC_TIME, 'C').

6. AGPL-3.0 Compliance:

   • Issue: AGPL requires open-sourcing if using in SaaS or proprietary software.
   • Fix: Review Astrodienst’s license or use a commercial license.

Debugging Tips

1. Error Codes:
   • Check `swephinfo